Hepatitis E
Hepatitis E virus, or HEV, is similar to hepatitis A virus in mode of transmission and the duration of the disease, although it tends to occur as part of large water- or food-borne epidemics. HEV spreads through contact with food or water contaminated by feces from an infected person. Rare in the U.S., the infection usually clears up after several weeks to a few months. At risk are international travelers, people living in areas where HEV outbreaks are common and people who have sex or live with an infected person. Pregnant women infected with HEV have a 20 percent risk of dying. To limit risk of HEV exposure, avoid tap water when traveling internationally and practice good hygiene and sanitation.
Blood pressure is the amount of force your blood exerts against the walls of your arteries. Normal blood pressure effectively and harmlessly pushes the blood from your heart to your body's organs and muscles so they can receive the oxygen and nutrients they need.
Blood pressure is variable -- it rises and falls during the day. When blood pressure stays elevated over time, however, it is called high blood pressure or hypertension.
According to the most recent estimates, up to 65 million Americans have hypertension, or high blood pressure, and nearly half are women, according to the American Heart Association. High blood pressure killed nearly 50,000 Americans in 2002, and was listed as a primary or contributing factor in 261,000 deaths.
Hypertension can occur in both children and adults, but it is more common in adults, particularly African Americans, overweight people, people who drink heavily (defined as more than two drinks a day for men and one drink a day for women), elderly and middle-aged people and women who are taking oral contraceptives. Additionally, people with diabetes, kidney disease or gout have a higher risk of hypertension. Overall, one in three American adults has hypertension.
More men than women have hypertension, until women reach menopause, when their risk becomes greater than men's s. About half of the 65 million Americans with high blood pressure are women About 20 percent of white women and 30 to 40 percent of African-American women have high blood pressure, and the prevalence rises to 80 percent in women over age 70.
Blood pressure is typically expressed as two numbers, one over the other, and is measured in millimeters of mercury (noted as mmHg). The first number is the systolic systolic blood pressure, the pressure used when the heart beats. The second number, or diastolic blood pressure, is the pressure that exists in the arteries between heartbeats.
Depending on your activities, your blood pressure may increase or decrease throughout the day. If you are not acutely ill, are over 18 years of age, and are not taking antihypertensive drugs, a blood pressure reading of less than 120 mmHg systolic and less than 80 mmHg diastolic (120/80) is considered normal.
If your blood pressure is between 120/80 mmHg and 139/89 mmHg, you havprehypertension. This means that you don't have high blood pressure now but are more likely to develop it in the future, and you have increased risk factors for cardiovascular disease and other conditions related to hypertension.
A blood pressure level of 140/90 mmHg or higher is considered high.
You may also have hypertension if either your systolic or diastolic is greater than or equal to 140 or 90 mmHg, respectively. That is, you can have isolated systolic or diastolic hypertension. Isolated systolic hypertension (ISH) This is the most common form of high blood pressure in older Americans. The National Heart, Lung and Blood Institute (NHLBI) estimates that 65 percent of people with hypertension over age 60 have ISH.
The cause of approximately 90 to 95 percent of all hypertension isn't known. This type of hypertension is called primary or essential high blood pressure. When the cause is known, it's called secondary hypertension. While there is no cure for hypertension, it is easily detected and is usually controllable.
Still, nearly one third of those who suffer from high blood pressure don't know they have it, and people can have high blood pressure for years without knowing they have it. That's why high blood pressure has been called "the silent killer."
Of those with hypertension, only 34 percent have the problem under control, defined as a level below 140/90 mm/Hg. Left untreated, hypertension can result in permanent damage to the small blood vessels of the body, which can damage vital organs and increase the risk of heart attack and stroke. It can also cause acute or chronic circulatory problems.
Even slightly elevated blood pressure levels can double your risk for coronary heart disease. In fact, recent studies show that in adults ages 40–89, the risk of death from heart disease and stroke begins to rise at blood pressures as low as 115/75. This risk doubles for each increased increment of 20 mm/Hg in systolic blood pressure or 10 mm/Hg in diastolic blood pressure. Consistent high blood pressure also increases your risk for congestive heart failure, and can lead to other problems such as:
Atherosclerosis: Plaque collects on the walls of hypertension-damaged blood vessels, which can eventually lead to blockages that may result in a stroke or heart attack. Although this plaque builds up for many reasons as you age, high blood pressure hastens the process.
Eye damage: High pressure in blood vessels can cause tiny hemorrhages in the retina, the light-sensitive membrane in the back of your eye on which images are formed. If this happens, you may lose some of your vision.
Heart enlargement or failure: There are two types of heart failure. In the first, the walls of the heart are weak and thin as a result of being stretched by increasing amounts of pooling blood in the heart. In the second, commonly seen in people with hypertension, the heart muscle enlarges in response to the higher pressure and increased workload. It becomes so big it begins to close off the ventricular chamber, decreasing the amount of blood that can fill the heart. This is called diastolic dysfunction, because the heart muscle can't relax normally and allow blood to fill the chamber.
Kidney damage and failure: Hypertension causes arteries going to your kidneys to become constricted, making them less efficient at filtering waste from your body. About 25 percent of people who require kidney dialysis have kidney failure due to hypertension. This is especially true in African Americans. Early treatment of hypertension can help prevent kidney damage.
You should have your blood pressure checked whenever you see a health care professional. Because blood pressure can be variable, it should be checked on several different days before a high blood pressure diagnosis is made. One elevated blood pressure reading doesn't necessarily mean you have high blood pressure, but it does warrant repeated measurement and means you have to watch your blood pressure carefully.
Dietary and lifestyle changes may help you control high blood pressure. If you have mild hypertension, you may be able to lower your blood pressure by reducing the amount of sodium (salt) in your diet, reducing fat intake, eating a diet high in fruits, vegetables and low-fat dairy (the DASH diet), and reducing alcohol consumption. If you are overweight, losing weight may reduce your blood pressure. Increasing your physical activity, even if you don't lose weight, can also reduce blood pressure.
For some people, lifestyle changes aren't enough to lower blood pressure. Luckily, high blood pressure can be treated very successfully with long-term medication.
Commonly prescribed drugs include diuretics, beta-blockers, angiotension inhibitors (ACEIs), calcium angiotensin blockers (AGBs), calcium channel blockers (CCBs). Because there is no cure for most hypertension cases, treatment generally must be carried out for life to prevent blood pressure from rising again.
Many of these drugs are also available to treat isolated systolic hypertension (ISH) to reduce your risk of coronary heart disease and stroke.
Causes of Hypertension
The 90 to 95 percent of hypertension cases in which the cause can't be determined are called essential or primary hypertension cases. Hypertension may also be a symptom of an identified problem (see below) that generally corrects itself when the identified cause is corrected. This type of high blood pressure is called secondary hypertension.
Possible causes of secondary hypertension include:
Any stress, which can be caused by pain, drug or alcohol withdrawal or high emotions
Use of birth control pills
preeclampsia (hypertension and increased urine protein levels sometimes caused by pregnancy)
Renal artery stenosis (narrowing of the arteries leading to your kidneys)
Use of steroids
Adrenal gland disease (Cushing's Disease) or adrenal tumors
Diabetic renal disease
Use of amphetamines, cocaine or other stimulants
Hyperthyroidism
A large intake of licorice root extract (equivalent to 25 to 40 licorice candies a day for several years)
The overuse of nicotine nasal sprays, gum, patches, and lozenges designed to help smokers kick the habit
Your health care professional should monitor your blood pressure if you are taking oral contraceptives. Your blood pressure should also be carefully monitored if you're pregnant, because some women develop pre-eclampsia-related hypertension during pregnancy. One of the leading causes of maternal death, pre-eclampsia is hypertension combined with protein in the urine and/or swollen hands and feet. It typically occurs after the 20th week of pregnancy. It can lead to premature and low-birthweight babies.
Thursday, November 22, 2007
Hepatities B & C
Hepatitis B
Hepatitis B vaccines have been available since 1982 and, as a result, the number of new infections per year has declined from an average of 260,000 in the 1980s to about 78,000 in 2001, according to the CDC. Approximately 1.25 million people are chronically infected with HBV in the U.S., of whom 20 to 30 percent acquired their infection in childhood. Death from chronic liver disease occurs in 15-25 percent of chronically infected persons. One leading mode of transmission is unsafe sex. The virus is also spread by shared needles, from a mother to her newborn, between children in daycare settings, and in health care settings. Screening of blood donors has virtually eliminated transmission via blood transfusion. All pregnant women in the US should be screened for hepatitis B. If infected, the baby will need to receive specific hepatitis B immune globulin and be vaccinated at birth.
Vaccination against hepatitis B is also recommended for:
All children under age 18
Persons with multiple sex partners or diagnosis of a sexually transmitted disease
Men who have sex with men
Sex contacts of infected persons
Injection drug users
Household contacts of chronically infected persons
Infants born to infected mothers
Infants/children of immigrants from areas with high rates of HBV infection
Health care and public safety workers
Hemodialysis patients
Patients with other liver diseases
Hepatitis C
Hepatitis C, or HCV, has been the focus of recent attention because an estimated 3.9 million Americans are believed to have been exposed and 2.7 million are chronically infected. Hepatitis C causes up to 10,000 deaths a year, due to complications of cirrhosis and liver cancer. Treatments are available but they are not effective in all patients. Most infections occurred in the 1970s and 1980s from contaminated blood used during transfusions and from injection drug use. The virus was first identified in 1988 and, in 1989, a reliable test was developed that could identify antibodies to the virus in blood supplies. Today, using more sensitive and specific antibody tests and RNA testing there is less than one case of HCV infection per million units of transfused blood.
HCV poses serious health problems for some people while for others there may be no long-term consequences. Natural history studies suggest that the rate of progression to cirrhosis (scarring of the liver) is highly variable, ranging from 0.5 to 25 percent of patients with chronic disease who have had the infection for 10 to 30 years. Liver cancer develops in approximately 2 percent of cirrhotic patients each year.
Although the annual number of new HCV infections has decreased dramatically-from a high of 240,000 in the 1980s to 25,000 in 2001-most infected people don't know they have the virus. Only recently have health officials made a concerted effort to notify those who received blood or blood products contaminated with HCV before routine screening began.
Testing for hepatitis C by detection of a specific antibody for the virus is recommended for injection drug users, recipients of blood clotting factors, hemodialysis patients, recipients of blood transfusions or solid organ transplants before 1992 and infants born to infected mothers (after 12 to 18 months).
Hepatitis D
Hepatitis D virus, or HDV, is uncommon, except in IV drug users. It can lead to cirrhosis in up to 70 percent of cases, often within a few years. HDV, acquired through contact with infected blood, occurs only in those already infected with hepatitis B. Also at risk are those with HBV who have sex or live with a person infected with HDV. For those not infected with HBV, a vaccine can shield them from
that virus and therefore provide protection against HDV as well.
Hepatitis B vaccines have been available since 1982 and, as a result, the number of new infections per year has declined from an average of 260,000 in the 1980s to about 78,000 in 2001, according to the CDC. Approximately 1.25 million people are chronically infected with HBV in the U.S., of whom 20 to 30 percent acquired their infection in childhood. Death from chronic liver disease occurs in 15-25 percent of chronically infected persons. One leading mode of transmission is unsafe sex. The virus is also spread by shared needles, from a mother to her newborn, between children in daycare settings, and in health care settings. Screening of blood donors has virtually eliminated transmission via blood transfusion. All pregnant women in the US should be screened for hepatitis B. If infected, the baby will need to receive specific hepatitis B immune globulin and be vaccinated at birth.
Vaccination against hepatitis B is also recommended for:
All children under age 18
Persons with multiple sex partners or diagnosis of a sexually transmitted disease
Men who have sex with men
Sex contacts of infected persons
Injection drug users
Household contacts of chronically infected persons
Infants born to infected mothers
Infants/children of immigrants from areas with high rates of HBV infection
Health care and public safety workers
Hemodialysis patients
Patients with other liver diseases
Hepatitis C
Hepatitis C, or HCV, has been the focus of recent attention because an estimated 3.9 million Americans are believed to have been exposed and 2.7 million are chronically infected. Hepatitis C causes up to 10,000 deaths a year, due to complications of cirrhosis and liver cancer. Treatments are available but they are not effective in all patients. Most infections occurred in the 1970s and 1980s from contaminated blood used during transfusions and from injection drug use. The virus was first identified in 1988 and, in 1989, a reliable test was developed that could identify antibodies to the virus in blood supplies. Today, using more sensitive and specific antibody tests and RNA testing there is less than one case of HCV infection per million units of transfused blood.
HCV poses serious health problems for some people while for others there may be no long-term consequences. Natural history studies suggest that the rate of progression to cirrhosis (scarring of the liver) is highly variable, ranging from 0.5 to 25 percent of patients with chronic disease who have had the infection for 10 to 30 years. Liver cancer develops in approximately 2 percent of cirrhotic patients each year.
Although the annual number of new HCV infections has decreased dramatically-from a high of 240,000 in the 1980s to 25,000 in 2001-most infected people don't know they have the virus. Only recently have health officials made a concerted effort to notify those who received blood or blood products contaminated with HCV before routine screening began.
Testing for hepatitis C by detection of a specific antibody for the virus is recommended for injection drug users, recipients of blood clotting factors, hemodialysis patients, recipients of blood transfusions or solid organ transplants before 1992 and infants born to infected mothers (after 12 to 18 months).
Hepatitis D
Hepatitis D virus, or HDV, is uncommon, except in IV drug users. It can lead to cirrhosis in up to 70 percent of cases, often within a few years. HDV, acquired through contact with infected blood, occurs only in those already infected with hepatitis B. Also at risk are those with HBV who have sex or live with a person infected with HDV. For those not infected with HBV, a vaccine can shield them from
that virus and therefore provide protection against HDV as well.
Hepatitis
Hepatitis
You've probably heard warnings about hepatitis, a category of viral infections that can cause serious liver damage and even lead to death. Hepatitis literally means inflammation of the liver (hepa = liver; it is = inflammation).
If you're having trouble keeping up with the alphabet soup of the different types of the virus you're not alone. There are six main types: A, B, C, D, E and G. For the most part, however, you need to concern yourself only with hepatitis A virus, hepatitis B virus and hepatitis C virus-referred to as HAV, HBV and HCV respectively.
The hepatitis viruses all cause acute inflammation of the liver, while some infections related to hepatitis B and C may become chronic. Although many hepatitis infections do not cause symptoms, in those that do, the leading symptoms are:
jaundice (yellowing of the skin and eyes)
fatigue, malaise
abdominal pain
appetite loss
nausea
diarrhea
vomiting
The good news is that vaccines against hepatitis A and hepatitis B have been introduced in the last 20 years. The U.S. Centers for Disease Control and Prevention (CDC) recommends that all children under 18 be vaccinated against hepatitis B (HBV), and that those at risk for either infection get the appropriate vaccination.
Hepatitis A
Hepatitis A, or HAV, causes about one third of all cases of acute hepatitis in the U.S., During epidemic years, the number of reported cases reached 35,000. In the late 1990s, hepatitis A vaccine was more widely used and the number of cases reached historic lows. However, health officials believe it is underreported because people often have no symptoms. HAV infection causes temporary symptoms and is not associated with chronic liver disease. Once you have had HAV you cannot get it again, although about 15 percent of people infected with the virus have prolonged or relapsing symptoms over a six to nine month period, according to the CDC.
HAV receives attention usually because of community outbreaks that result from person-to-person transmission, primarily through daycares and contact with contaminated food or water. In fact, the FDA recently (Nov. 2003) issued a warning advising the public that several recent hepatitis A outbreaks have been associated with eating raw or undercooked green onions (scallions) and offered the following advice to consumers:
Cook green onions thoroughly. This minimizes the risk of illness by reducing or eliminating the virus. Cook in a casserole or sauté in a skillet.
Check food purchased at restaurants and delicatessens and ask whether menu items contain raw or lightly cooked green onions. Consumers who wish to avoid food that contains raw or lightly cooked green onions should specifically request that raw or lightly cooked green onions not be added to their food. Foods such as freshly prepared salsa and green salads often contain raw green onions.
For most women, the biggest risk factors are sexual or household contact with an infected person, or travel to countries where hepatitis A is common. You cannot get the infection through casual contact.
For hepatitis A, vaccination is recommended for the following persons:
Children two years of age and older
Travelers to areas with increased rates of hepatitis A (view map, see below for link)
Men who have sex with men
Injecting and non-injecting drug users
Persons with clotting-factor disorders (e.g., hemophilia)
Persons with chronic liver disease
You've probably heard warnings about hepatitis, a category of viral infections that can cause serious liver damage and even lead to death. Hepatitis literally means inflammation of the liver (hepa = liver; it is = inflammation).
If you're having trouble keeping up with the alphabet soup of the different types of the virus you're not alone. There are six main types: A, B, C, D, E and G. For the most part, however, you need to concern yourself only with hepatitis A virus, hepatitis B virus and hepatitis C virus-referred to as HAV, HBV and HCV respectively.
The hepatitis viruses all cause acute inflammation of the liver, while some infections related to hepatitis B and C may become chronic. Although many hepatitis infections do not cause symptoms, in those that do, the leading symptoms are:
jaundice (yellowing of the skin and eyes)
fatigue, malaise
abdominal pain
appetite loss
nausea
diarrhea
vomiting
The good news is that vaccines against hepatitis A and hepatitis B have been introduced in the last 20 years. The U.S. Centers for Disease Control and Prevention (CDC) recommends that all children under 18 be vaccinated against hepatitis B (HBV), and that those at risk for either infection get the appropriate vaccination.
Hepatitis A
Hepatitis A, or HAV, causes about one third of all cases of acute hepatitis in the U.S., During epidemic years, the number of reported cases reached 35,000. In the late 1990s, hepatitis A vaccine was more widely used and the number of cases reached historic lows. However, health officials believe it is underreported because people often have no symptoms. HAV infection causes temporary symptoms and is not associated with chronic liver disease. Once you have had HAV you cannot get it again, although about 15 percent of people infected with the virus have prolonged or relapsing symptoms over a six to nine month period, according to the CDC.
HAV receives attention usually because of community outbreaks that result from person-to-person transmission, primarily through daycares and contact with contaminated food or water. In fact, the FDA recently (Nov. 2003) issued a warning advising the public that several recent hepatitis A outbreaks have been associated with eating raw or undercooked green onions (scallions) and offered the following advice to consumers:
Cook green onions thoroughly. This minimizes the risk of illness by reducing or eliminating the virus. Cook in a casserole or sauté in a skillet.
Check food purchased at restaurants and delicatessens and ask whether menu items contain raw or lightly cooked green onions. Consumers who wish to avoid food that contains raw or lightly cooked green onions should specifically request that raw or lightly cooked green onions not be added to their food. Foods such as freshly prepared salsa and green salads often contain raw green onions.
For most women, the biggest risk factors are sexual or household contact with an infected person, or travel to countries where hepatitis A is common. You cannot get the infection through casual contact.
For hepatitis A, vaccination is recommended for the following persons:
Children two years of age and older
Travelers to areas with increased rates of hepatitis A (view map, see below for link)
Men who have sex with men
Injecting and non-injecting drug users
Persons with clotting-factor disorders (e.g., hemophilia)
Persons with chronic liver disease
Risk Factors
Risk Factors for Heart Disease
Over the last two decades, researchers have unearthed many risk factors for developing cardiovascular diseases. These include:
Smoking. Smoking accelerates the development of atherosclerosis by constricting blood vessels, accelerating the formation of blood clots and restricting the amount of oxygen the blood supplies. Smokers who have heart attacks and strokes are more likely to die from them.
High cholesterol levels. According to the National Cholesterol Education Program (NCEP), elevated LDL cholesterol is a major cause of coronary heart disease. That's why the NCEP panel recommends aggressive treatment. Treatment may include lifestyle changes, such as exercising more and reducing the amount of saturated fat in your diet, and medication. A combination of approaches is typically recommended.
Optimal cholesterol levels for healthy women are:
Total cholesterol: less than 200 mg/dL
HDL cholesterol: above 60 mg/dL. This range is considered to be protective against heart disease, while levels less than 40 mg/dL are considered a major risk factor for developing heart disease.
LDL cholesterol: less than 100 mg/dL
Triglycerides: less than 150 mg/dL
High blood pressure (hypertension). When the heart works too hard to pump blood through the body, the intensity can damage the walls of the arteries of the heart and body.
A blood pressure reading records a systolic blood pressure—the highest pressure measured when the heart contracts with each beat, and a diastolic blood pressure—the lowest pressure measured in the arteries when the heart relaxes between beats. Optimal blood pressure is less than 120/80mm hg, read "120 over 80." Hypertension—high blood pressure—is defined as systolic pressure greater than or equal to 140 mm hg or diastolic pressure greater than or equal to 90 mm hg.
There is another category called "prehypertension" you should be aware of. This designation is made when the systolic pressure is 120 to139, or diastolic pressure is 80 to 89, and means you have a significant risk of developing high blood pressure, or hypertension.
Diabetes. Having diabetes poses as great a risk for having a heart attack in 10 years as heart disease itself, according to NHLBI. In fact, cardiovascular disease is the leading cause of diabetes-related deaths. People with diabetes who have not yet had a heart attack have the same risk of future heart attack as someone with known coronary heart disease. Because their risk of heart attack is so high, NHLBI recommends that people with diabetes be treated aggressively with LDL-cholesterol lowering medication and carefully manage their blood sugar to reduce their cardiovascular risk.
Age. Generally, women over age 55 and men over age 45 are at greatest risk for developing atherosclerosis. The risk of cardiovascular events increases with age.
Family history. Family history is one of the biggest risk factors overall for atherosclerosis. Your risk is greater if your father or brother was diagnosed before age 55, if your mother or sister was diagnosed before age 65, or if you have a sibling with early coronary disease.
Obesity. Overweight women are much more likely to develop heart-related problems, even if they have no other risk factors. Excess body weight in women is linked with coronary heart disease, stroke, congestive heart failure and death from heart-related causes.
Inactivity. Not exercising contributes directly to heart-related problems and increases the likelihood that you'll develop other risk factors, such as high blood pressure and diabetes.
Metabolic syndrome. This deadly quartet of abdominal obesity, high blood pressure, glucose intolerance (or pre-diabetes) and abnormal cholesterol is associated with a markedly increased risk of cardiovascular disease.
Homocysteine. Homocysteine is an amino acid normally found in the body. Studies suggest that high blood levels of this substance may increase the risk of heart disease, stroke and peripheral vascular disease.
C-Reactive protein (CRP), a high blood level of CRP, a sign of inflammation, may mean that the walls of the arteries in your heart are inflamed, which may raise your heart disease risk.
A blood test called the high sensitivity C-reactive protein blood test (hs-CRP) is now widely available. Most studies show that in healthy people, the higher the hs-CRP levels, the higher the risk of developing a future heart attack. In fact, scientific studies have found that the risk for heart attack in people in the upper third of hs-CRP levels is twice that of those with hs-CRP levels in the lower third. Recent studies also found a link between hs-CRP to sudden cardiac death and peripheral arterial disease.
According to the American Heart Association, numerous studies have examined whether hs-CRP can predict recurrent cardiovascular disease and stroke and death in various settings. High levels of hs-CRP consistently predict new coronary events in people with unstable angina and acute myocardial infarction (heart attack). Higher hs-CRP levels are also associated with lower survival rate in these people. Many studies suggested that after adjusting for other prognostic factors, hs-CRP was still useful as a risk predictor.
It is not yet known whether specific interventions will benefit those who have high hs-CRP, however aspirin therapy and cholesterol-lowering drugs might be helpful in these individuals.
The American Heart Association and the U.S. Centers for Disease Control and Prevention issued new guidelines for the blood test in January 2003. The guidelines recommend limiting the use of the CRP test as a discretionary tool for evaluating people of moderate risk, and not as a means of screening the entire adult population, as insufficient scientific evidence supports widespread use at this time.
Stress. Although stress has been implicated in the development of atherosclerosis, its exact relationship to heart disease has not been determined. Regular exercise can reduce stress and improve your mood.
Postmenopausal status. Your risk of developing atherosclerosis and heart disease increases once you reach menopause. Prior to menopause, women are mainly protected from heart disease by estrogen, the reproductive hormone produced by the ovaries. Among its many roles, estrogen helps keep arteries free from plaque by improving the ratio of LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol. It also increases the amount of HDL cholesterol, which helps clear arteries of LDL cholesterol—the kind that most contributes to plaque build up.
Over the last two decades, researchers have unearthed many risk factors for developing cardiovascular diseases. These include:
Smoking. Smoking accelerates the development of atherosclerosis by constricting blood vessels, accelerating the formation of blood clots and restricting the amount of oxygen the blood supplies. Smokers who have heart attacks and strokes are more likely to die from them.
High cholesterol levels. According to the National Cholesterol Education Program (NCEP), elevated LDL cholesterol is a major cause of coronary heart disease. That's why the NCEP panel recommends aggressive treatment. Treatment may include lifestyle changes, such as exercising more and reducing the amount of saturated fat in your diet, and medication. A combination of approaches is typically recommended.
Optimal cholesterol levels for healthy women are:
Total cholesterol: less than 200 mg/dL
HDL cholesterol: above 60 mg/dL. This range is considered to be protective against heart disease, while levels less than 40 mg/dL are considered a major risk factor for developing heart disease.
LDL cholesterol: less than 100 mg/dL
Triglycerides: less than 150 mg/dL
High blood pressure (hypertension). When the heart works too hard to pump blood through the body, the intensity can damage the walls of the arteries of the heart and body.
A blood pressure reading records a systolic blood pressure—the highest pressure measured when the heart contracts with each beat, and a diastolic blood pressure—the lowest pressure measured in the arteries when the heart relaxes between beats. Optimal blood pressure is less than 120/80mm hg, read "120 over 80." Hypertension—high blood pressure—is defined as systolic pressure greater than or equal to 140 mm hg or diastolic pressure greater than or equal to 90 mm hg.
There is another category called "prehypertension" you should be aware of. This designation is made when the systolic pressure is 120 to139, or diastolic pressure is 80 to 89, and means you have a significant risk of developing high blood pressure, or hypertension.
Diabetes. Having diabetes poses as great a risk for having a heart attack in 10 years as heart disease itself, according to NHLBI. In fact, cardiovascular disease is the leading cause of diabetes-related deaths. People with diabetes who have not yet had a heart attack have the same risk of future heart attack as someone with known coronary heart disease. Because their risk of heart attack is so high, NHLBI recommends that people with diabetes be treated aggressively with LDL-cholesterol lowering medication and carefully manage their blood sugar to reduce their cardiovascular risk.
Age. Generally, women over age 55 and men over age 45 are at greatest risk for developing atherosclerosis. The risk of cardiovascular events increases with age.
Family history. Family history is one of the biggest risk factors overall for atherosclerosis. Your risk is greater if your father or brother was diagnosed before age 55, if your mother or sister was diagnosed before age 65, or if you have a sibling with early coronary disease.
Obesity. Overweight women are much more likely to develop heart-related problems, even if they have no other risk factors. Excess body weight in women is linked with coronary heart disease, stroke, congestive heart failure and death from heart-related causes.
Inactivity. Not exercising contributes directly to heart-related problems and increases the likelihood that you'll develop other risk factors, such as high blood pressure and diabetes.
Metabolic syndrome. This deadly quartet of abdominal obesity, high blood pressure, glucose intolerance (or pre-diabetes) and abnormal cholesterol is associated with a markedly increased risk of cardiovascular disease.
Homocysteine. Homocysteine is an amino acid normally found in the body. Studies suggest that high blood levels of this substance may increase the risk of heart disease, stroke and peripheral vascular disease.
C-Reactive protein (CRP), a high blood level of CRP, a sign of inflammation, may mean that the walls of the arteries in your heart are inflamed, which may raise your heart disease risk.
A blood test called the high sensitivity C-reactive protein blood test (hs-CRP) is now widely available. Most studies show that in healthy people, the higher the hs-CRP levels, the higher the risk of developing a future heart attack. In fact, scientific studies have found that the risk for heart attack in people in the upper third of hs-CRP levels is twice that of those with hs-CRP levels in the lower third. Recent studies also found a link between hs-CRP to sudden cardiac death and peripheral arterial disease.
According to the American Heart Association, numerous studies have examined whether hs-CRP can predict recurrent cardiovascular disease and stroke and death in various settings. High levels of hs-CRP consistently predict new coronary events in people with unstable angina and acute myocardial infarction (heart attack). Higher hs-CRP levels are also associated with lower survival rate in these people. Many studies suggested that after adjusting for other prognostic factors, hs-CRP was still useful as a risk predictor.
It is not yet known whether specific interventions will benefit those who have high hs-CRP, however aspirin therapy and cholesterol-lowering drugs might be helpful in these individuals.
The American Heart Association and the U.S. Centers for Disease Control and Prevention issued new guidelines for the blood test in January 2003. The guidelines recommend limiting the use of the CRP test as a discretionary tool for evaluating people of moderate risk, and not as a means of screening the entire adult population, as insufficient scientific evidence supports widespread use at this time.
Stress. Although stress has been implicated in the development of atherosclerosis, its exact relationship to heart disease has not been determined. Regular exercise can reduce stress and improve your mood.
Postmenopausal status. Your risk of developing atherosclerosis and heart disease increases once you reach menopause. Prior to menopause, women are mainly protected from heart disease by estrogen, the reproductive hormone produced by the ovaries. Among its many roles, estrogen helps keep arteries free from plaque by improving the ratio of LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol. It also increases the amount of HDL cholesterol, which helps clear arteries of LDL cholesterol—the kind that most contributes to plaque build up.
Glaucoma forms
There are several forms of glaucoma, including the following:
Open-angle. In this most common form of glaucoma, the angle where the cornea and the iris meet is open, but the aqueous humor fluid passes too slowly through the meshwork drain. As a result, the pressure in the eye gradually increases, compressing cells in the optic nerve. If left untreated, the compression eventually will cause the optic nerve cells to die, producing blindness.
Open-angle glaucoma occurs in about one percent of all Americans age 50 and older, according to the Glaucoma Foundation. This type of glaucoma is the leading cause of blindness among African Americans, occurring six to eight more times more often, and at earlier ages than in Caucasians, reports the American Academy of Ophthalmology. Early detection is essential to managing open-angle glaucoma and minimizing vision loss. Treatments include medications in the form of eye drops and pills to reduce the amount of aqueous humor in the eye or improve its drainage, both of which help reduce intraocular pressure. Surgery, either by using a laser or by conventional means, also may be recommended.
Angle-closure. This type of glaucoma affects nearly 500,000 people in the U.S. according to the Glaucoma Foundation. It occurs when the angle between the iris and the cornea is closed, and the aqueous humor cannot drain, producing high eye pressure. This form of glaucoma is more common among people of Asian or Eskimo descent, especially older women. Other risk factors include old age, a family history of the condition and farsightedness.
Angle-closure glaucoma occurs in two forms, acute and chronic. The acute version can be a sudden, painful attack requiring emergency treatment. The chronic version occurs over time, producing no recognizable symptoms before vision is lost.
People with angle-closure glaucoma tend to have a smaller-than-average anterior chamber, and the angle between the iris and the cornea where the aqueous humor drains is also smaller. When the lens naturally grows larger with advancing age, the aqueous humor has difficulty flowing in the tight space, causing the fluid to build up behind the iris, narrowing the angle even more. When the pupil dilates, such as when entering a dark room, or when experiencing anxiety or stress, the angle narrows even further, and the iris is forced against the trabecular meshwork, stopping drainage. Without drainage, pressure in the eye squeezes and damages the optic nerve.
In acute angle-closure glaucoma, intraocular pressure rises suddenly, producing pain. The eye turns red, the cornea swells and clouds, vision may be blurred, and lights may appear as if they have halos. Treatment with eye drops that help reduce the eye's production of aqueous humor and constrict the pupil may stop an acute attack. Surgery to improve the flow of the aqueous humor is usually recommended.
In chronic angle-closure glaucoma, the iris gradually closes over the drain, causing no recognizable symptoms. As this occurs, scars form between the iris and the drain, eventually blocking it and driving up intraocular pressure. Treatment may include eye drops and surgery.
Although rare in women, a problem called pigment dispersion syndrome can cause angle-closure glaucoma. The syndrome occurs when grains of pigment on the back of the iris flake off into the aqueous humor, eventually clogging the drainage meshwork and raising eye pressure. The syndrome produces no noticeable symptoms, but can be detected and monitored in routine eye examinations. About 30 percent of patients with pigment dispersion syndrome develop angle-closure glaucoma, according to the Glaucoma Research Foundation.
Normal-tension. Some people with normal eye pressure develop glaucoma, a disease known as low-tension or normal-tension glaucoma (NTG). The Glaucoma Research Foundation estimates that of the three million Americans with glaucoma, about 25 percent to 33 percent may have this form of disease in which eye pressures are within the normal range, but the optic nerve progressively deteriorates. The progression of the disease is faster in those who have the specific risk factors for progression, namely, migraine, disc hemorrhage (a very small bleed on the optic disc, most often seen in those with NTG as opposed to other forms of glaucoma), female gender and racial heritage. Research is continuing on this form of glaucoma, which is thought to be related to poor blood flow to the optic nerve.
Open-angle. In this most common form of glaucoma, the angle where the cornea and the iris meet is open, but the aqueous humor fluid passes too slowly through the meshwork drain. As a result, the pressure in the eye gradually increases, compressing cells in the optic nerve. If left untreated, the compression eventually will cause the optic nerve cells to die, producing blindness.
Open-angle glaucoma occurs in about one percent of all Americans age 50 and older, according to the Glaucoma Foundation. This type of glaucoma is the leading cause of blindness among African Americans, occurring six to eight more times more often, and at earlier ages than in Caucasians, reports the American Academy of Ophthalmology. Early detection is essential to managing open-angle glaucoma and minimizing vision loss. Treatments include medications in the form of eye drops and pills to reduce the amount of aqueous humor in the eye or improve its drainage, both of which help reduce intraocular pressure. Surgery, either by using a laser or by conventional means, also may be recommended.
Angle-closure. This type of glaucoma affects nearly 500,000 people in the U.S. according to the Glaucoma Foundation. It occurs when the angle between the iris and the cornea is closed, and the aqueous humor cannot drain, producing high eye pressure. This form of glaucoma is more common among people of Asian or Eskimo descent, especially older women. Other risk factors include old age, a family history of the condition and farsightedness.
Angle-closure glaucoma occurs in two forms, acute and chronic. The acute version can be a sudden, painful attack requiring emergency treatment. The chronic version occurs over time, producing no recognizable symptoms before vision is lost.
People with angle-closure glaucoma tend to have a smaller-than-average anterior chamber, and the angle between the iris and the cornea where the aqueous humor drains is also smaller. When the lens naturally grows larger with advancing age, the aqueous humor has difficulty flowing in the tight space, causing the fluid to build up behind the iris, narrowing the angle even more. When the pupil dilates, such as when entering a dark room, or when experiencing anxiety or stress, the angle narrows even further, and the iris is forced against the trabecular meshwork, stopping drainage. Without drainage, pressure in the eye squeezes and damages the optic nerve.
In acute angle-closure glaucoma, intraocular pressure rises suddenly, producing pain. The eye turns red, the cornea swells and clouds, vision may be blurred, and lights may appear as if they have halos. Treatment with eye drops that help reduce the eye's production of aqueous humor and constrict the pupil may stop an acute attack. Surgery to improve the flow of the aqueous humor is usually recommended.
In chronic angle-closure glaucoma, the iris gradually closes over the drain, causing no recognizable symptoms. As this occurs, scars form between the iris and the drain, eventually blocking it and driving up intraocular pressure. Treatment may include eye drops and surgery.
Although rare in women, a problem called pigment dispersion syndrome can cause angle-closure glaucoma. The syndrome occurs when grains of pigment on the back of the iris flake off into the aqueous humor, eventually clogging the drainage meshwork and raising eye pressure. The syndrome produces no noticeable symptoms, but can be detected and monitored in routine eye examinations. About 30 percent of patients with pigment dispersion syndrome develop angle-closure glaucoma, according to the Glaucoma Research Foundation.
Normal-tension. Some people with normal eye pressure develop glaucoma, a disease known as low-tension or normal-tension glaucoma (NTG). The Glaucoma Research Foundation estimates that of the three million Americans with glaucoma, about 25 percent to 33 percent may have this form of disease in which eye pressures are within the normal range, but the optic nerve progressively deteriorates. The progression of the disease is faster in those who have the specific risk factors for progression, namely, migraine, disc hemorrhage (a very small bleed on the optic disc, most often seen in those with NTG as opposed to other forms of glaucoma), female gender and racial heritage. Research is continuing on this form of glaucoma, which is thought to be related to poor blood flow to the optic nerve.
Glaucoma
Glaucoma
Often called the "sneak thief of sight," glaucoma refers to a group of eye diseases that damage the nerves carrying images from the eye to the brain. It is a leading cause of blindness in the U.S., accounting for nine to 12 percent of all blindness, according to Prevent Blindness America. The organization estimates that one in every 30 Americans age 40 and older has the disease, but half don't know it. Glaucoma usually produces no symptoms until the disease has progressed to the point of robbing a person's sight.
Although glaucoma has no cure, it can be controlled and vision maintained if it is caught early. That's why comprehensive eye examinations are recommended at least every two years for those at increased risk for the disease. Although anyone can get glaucoma, the risk is higher for those over age 60, those who have a family history of the condition, and African Americans. The National Eye Institute reports that African Americans are five times more likely than Caucasians to develop glaucoma. The risk of blindness from glaucoma is four times greater in African Americans than Caucasians overall, and 15 times greater in African Americans age 45 to 65 than in Caucasians of the same age, according to the institute.
Additional risk factors include:
Diabetes
nearsightedness, called myopia
regular, long-term steroid or cortisone use
previous eye injury
Another risk factor for glaucoma is high pressure within the eye. Pressure in the eye is known as intraocular pressure. It's a common misconception that having high intraocular pressure means you're a victim of glaucoma. In fact, you can have high intraocular pressure, known as ocular hypertension, and not have glaucoma. Whether you develop glaucoma depends on how much pressure your optic nerve-the bundle of 1.2 million nerve fibers that transmits images from the eye to the brain-can take without being damaged.
The first step in understanding glaucoma and its relationship to intraocular pressure is learning how the eye works. The outer protective layer of eye includes clear tissue through which light enters the eye, known as the cornea. The iris is the colored part of the eye that contains muscles that make the pupil (the dark-colored area in the center of the eye that lets light into the eye) open and close. Located behind the iris is the lens, a transparent structure with an outward curve on both sides that focuses light onto the retina at the back of the eye. The retina is made of light-sensitive tissue that sends visual messages via nerve impulses to the brain through the optic nerve. The brain then processes the nerve signals into the images you see.
The anterior chamber is a space in the eye bordered by the cornea, iris, pupil and lens. Flowing through this chamber is a liquid, called the aqueous humor, which supplies oxygen and nutrients to the cornea and lens, and helps maintain the shape of the eyeball. A tiny gland, called the ciliary body, located behind the iris produces the fluid. The fluid travels from the gland through the pupil into the anterior chamber, exiting at an angle where the cornea and the iris meet. At the angle is a spongy mesh of tissue that works like a drain, called the trabecular meshwork.
Often called the "sneak thief of sight," glaucoma refers to a group of eye diseases that damage the nerves carrying images from the eye to the brain. It is a leading cause of blindness in the U.S., accounting for nine to 12 percent of all blindness, according to Prevent Blindness America. The organization estimates that one in every 30 Americans age 40 and older has the disease, but half don't know it. Glaucoma usually produces no symptoms until the disease has progressed to the point of robbing a person's sight.
Although glaucoma has no cure, it can be controlled and vision maintained if it is caught early. That's why comprehensive eye examinations are recommended at least every two years for those at increased risk for the disease. Although anyone can get glaucoma, the risk is higher for those over age 60, those who have a family history of the condition, and African Americans. The National Eye Institute reports that African Americans are five times more likely than Caucasians to develop glaucoma. The risk of blindness from glaucoma is four times greater in African Americans than Caucasians overall, and 15 times greater in African Americans age 45 to 65 than in Caucasians of the same age, according to the institute.
Additional risk factors include:
Diabetes
nearsightedness, called myopia
regular, long-term steroid or cortisone use
previous eye injury
Another risk factor for glaucoma is high pressure within the eye. Pressure in the eye is known as intraocular pressure. It's a common misconception that having high intraocular pressure means you're a victim of glaucoma. In fact, you can have high intraocular pressure, known as ocular hypertension, and not have glaucoma. Whether you develop glaucoma depends on how much pressure your optic nerve-the bundle of 1.2 million nerve fibers that transmits images from the eye to the brain-can take without being damaged.
The first step in understanding glaucoma and its relationship to intraocular pressure is learning how the eye works. The outer protective layer of eye includes clear tissue through which light enters the eye, known as the cornea. The iris is the colored part of the eye that contains muscles that make the pupil (the dark-colored area in the center of the eye that lets light into the eye) open and close. Located behind the iris is the lens, a transparent structure with an outward curve on both sides that focuses light onto the retina at the back of the eye. The retina is made of light-sensitive tissue that sends visual messages via nerve impulses to the brain through the optic nerve. The brain then processes the nerve signals into the images you see.
The anterior chamber is a space in the eye bordered by the cornea, iris, pupil and lens. Flowing through this chamber is a liquid, called the aqueous humor, which supplies oxygen and nutrients to the cornea and lens, and helps maintain the shape of the eyeball. A tiny gland, called the ciliary body, located behind the iris produces the fluid. The fluid travels from the gland through the pupil into the anterior chamber, exiting at an angle where the cornea and the iris meet. At the angle is a spongy mesh of tissue that works like a drain, called the trabecular meshwork.
Diseases
About The Diseases
Alpha-1 antitrypsin (AAT) deficiency leads to lung damage and emphysema by the third or fourth decade of life. Liver disease may occur in the first few months of life. The condition is worsened by smoking. A replacement therapy is available but in chronically short supply, and it is not known how effective this is once disease has developed or which people would benefit most. You should consider carrier screening if you have a family history of the disease.
Celiac disease is the most common genetic disease in Europe affecting, for example, about one in 250 people in Italy and one in 300 in Ireland. In celiac disease, a protein called gluten (found in grains) provokes the body's immune system to destroy the small intestine's nutrient-absorbing villi. This destruction leads to malnourishment, but with a gluten-free diet, the villi heal. A gluten-free diet means avoiding all foods that contain wheat, rye, barley, and possibly oats--in other words, most grain, pasta, cereal and many processed foods. Despite these restrictions, people with celiac disease can eat a well-balanced diet with a variety of foods, including bread and pasta. For example, instead of wheat flour, people can use potato, rice, soy or bean flour. Or, they can buy gluten-free bread, pasta and other products from special food companies. The disease is believed to be underdiagnosed in the U.S., where the time between the first symptoms and diagnosis averages about 10 years. Children of a person with celiac disease have about a five to 10 percent chance of developing the disease. You may want to consider screening for yourself or a child if a close relative has celiac disease or symptoms such as anemia, delayed growth or weight loss appear. There is an increased incidence of celiac disease in individuals with Down syndrome.
Congenital adrenal hyperplasia (CAH) is caused by insufficient production of an essential chemical called cortisol. Children with CAH may have male features, such as excess facial hair, and tend to stop growing early and have trouble fighting infections and retaining salt. Girls with the severe form of the condition may have genital defects. The mild form has similar, but less pronounced, symptoms and may go undiagnosed. You may want to consider screening if you have a family history of the disease. During pregnancy, treating the mother can prevent the severe manifestations of CAH.
Cystic fibrosis is characterized by the production of thick mucus, leading to pulmonary and digestive problems. The disease is caused by a mutated CFTR gene (cystic fibrosis transmembrane regulator). About one in 25 Caucasian Americans is a carrier of a mutation in this gene. Cystic fibrosis occurs most frequently in Caucasians of northern European origin. Because there are many possible disease-causing mutations in the gene, most tests are only about 80 to 85 percent accurate and this may be lower in some ethnic groups. Tests for Ashkenazi Jewish carriers are 97 percent accurate, however, because there are three specific mutations in this population for this condition.
Fragile X syndrome is an X-linked recessive disorder that is the leading cause of genetically inherited mental retardation. Because the mutation (in a gene called FMR-1) is X-linked, boys are affected more frequently and more severely; often women are carriers with no or less severe symptoms, however, females can be affected. The mutation consists of segments of unstable DNA that are repeated; the repeats lengthen with each succeeding generation, leading to greater impairment in offspring. Consider carrier screening if you have a family history of Fragile X or mental retardation in male relatives.
Hemophilia A and B are X-linked recessive disorders characterized by low levels or absence of one of two essential blood-clotting proteins. About 20,000 males suffer from hemophilia, with hemophilia A accounting for 85 percent of cases. Treatment with the clotting proteins is expensive. Consider carrier testing if you have a family history of hemophilia or excessive bleeding.
Phenylketonuria, or PKU, is characterized by an inability to metabolize an amino acid called phenylalanine. Buildup of the chemical causes mental retardation, but state-mandated screening programs are able to identify newborns with PKU so that a special phenylalanine-free diet can be started to prevent retardation and other problems. If you were diagnosed with PKU as a child, a special diet is called for during pregnancy. You should consider carrier screening if you have a family history of the disease.
Sickle cell disease is a blood disorder caused by a mutation in the gene that expresses the hemoglobin protein. The disease is characterized by anemia and periodic episodes of pain. Hemoglobin, the substances that carries oxygen in red blood cells, forms uncharacteristic, rodlike clusters in the cells, giving them a sickle shape and impeding their passage in small blood vessels. The cells create a bottleneck that deprives tissues of oxygen and causes pain. The cells die more quickly than normal red blood cells, leaving the body chronically short of such cells and anemic. About one in 12 African Americans is a carrier.
Thalassemia is a term that covers a range of related anemias that vary in severity. A baby with thalassemia major may appear normal during the first year but subsequently develops symptoms such as jaundice (yellowed skin) and low appetite. If untreated, enlargement of the liver and spleen can occur, sometimes leading to heart failure or heightened susceptibility to life-threatening infections.
Von Hippel-Lindau disease (VHL) is a rare, genetic multi-system disorder characterized by the abnormal growth of tumors in certain parts of the body (angiomatosis). The tumors of the central nervous system (CNS) are benign and are comprised of a nest of blood vessels and are called hemangioblastomas (or angiomas in the eye). Hemangioblastomas may develop in the brain, the retina of the eyes, and other areas of the nervous system. Other types of tumors develop in the adrenal glands, the kidneys or the pancreas. Gene testing is available.
Recessive Genetic Conditions More Prevalent in Individuals of Ashkenazi Jewish Descent
Canavan disease is a neurodegenerative disease characterized by lack of the aspartoacylase enzyme, which is critical for central nervous system development and function. The progression is similar to Tay-Sachs disease, and affected children usually die by age five. Your doctor, even an ob/gyn, may not be aware of the risk for Canavan disease. The carrier rate is about one in 40 among Ashkenazi Jews.
Congenital deafness can be caused by one of two changes in a gene called Connexin 26. About one in 21 individuals of Ashkenazi Jewish descent has one of the two mutations.
Alpha-1 antitrypsin (AAT) deficiency leads to lung damage and emphysema by the third or fourth decade of life. Liver disease may occur in the first few months of life. The condition is worsened by smoking. A replacement therapy is available but in chronically short supply, and it is not known how effective this is once disease has developed or which people would benefit most. You should consider carrier screening if you have a family history of the disease.
Celiac disease is the most common genetic disease in Europe affecting, for example, about one in 250 people in Italy and one in 300 in Ireland. In celiac disease, a protein called gluten (found in grains) provokes the body's immune system to destroy the small intestine's nutrient-absorbing villi. This destruction leads to malnourishment, but with a gluten-free diet, the villi heal. A gluten-free diet means avoiding all foods that contain wheat, rye, barley, and possibly oats--in other words, most grain, pasta, cereal and many processed foods. Despite these restrictions, people with celiac disease can eat a well-balanced diet with a variety of foods, including bread and pasta. For example, instead of wheat flour, people can use potato, rice, soy or bean flour. Or, they can buy gluten-free bread, pasta and other products from special food companies. The disease is believed to be underdiagnosed in the U.S., where the time between the first symptoms and diagnosis averages about 10 years. Children of a person with celiac disease have about a five to 10 percent chance of developing the disease. You may want to consider screening for yourself or a child if a close relative has celiac disease or symptoms such as anemia, delayed growth or weight loss appear. There is an increased incidence of celiac disease in individuals with Down syndrome.
Congenital adrenal hyperplasia (CAH) is caused by insufficient production of an essential chemical called cortisol. Children with CAH may have male features, such as excess facial hair, and tend to stop growing early and have trouble fighting infections and retaining salt. Girls with the severe form of the condition may have genital defects. The mild form has similar, but less pronounced, symptoms and may go undiagnosed. You may want to consider screening if you have a family history of the disease. During pregnancy, treating the mother can prevent the severe manifestations of CAH.
Cystic fibrosis is characterized by the production of thick mucus, leading to pulmonary and digestive problems. The disease is caused by a mutated CFTR gene (cystic fibrosis transmembrane regulator). About one in 25 Caucasian Americans is a carrier of a mutation in this gene. Cystic fibrosis occurs most frequently in Caucasians of northern European origin. Because there are many possible disease-causing mutations in the gene, most tests are only about 80 to 85 percent accurate and this may be lower in some ethnic groups. Tests for Ashkenazi Jewish carriers are 97 percent accurate, however, because there are three specific mutations in this population for this condition.
Fragile X syndrome is an X-linked recessive disorder that is the leading cause of genetically inherited mental retardation. Because the mutation (in a gene called FMR-1) is X-linked, boys are affected more frequently and more severely; often women are carriers with no or less severe symptoms, however, females can be affected. The mutation consists of segments of unstable DNA that are repeated; the repeats lengthen with each succeeding generation, leading to greater impairment in offspring. Consider carrier screening if you have a family history of Fragile X or mental retardation in male relatives.
Hemophilia A and B are X-linked recessive disorders characterized by low levels or absence of one of two essential blood-clotting proteins. About 20,000 males suffer from hemophilia, with hemophilia A accounting for 85 percent of cases. Treatment with the clotting proteins is expensive. Consider carrier testing if you have a family history of hemophilia or excessive bleeding.
Phenylketonuria, or PKU, is characterized by an inability to metabolize an amino acid called phenylalanine. Buildup of the chemical causes mental retardation, but state-mandated screening programs are able to identify newborns with PKU so that a special phenylalanine-free diet can be started to prevent retardation and other problems. If you were diagnosed with PKU as a child, a special diet is called for during pregnancy. You should consider carrier screening if you have a family history of the disease.
Sickle cell disease is a blood disorder caused by a mutation in the gene that expresses the hemoglobin protein. The disease is characterized by anemia and periodic episodes of pain. Hemoglobin, the substances that carries oxygen in red blood cells, forms uncharacteristic, rodlike clusters in the cells, giving them a sickle shape and impeding their passage in small blood vessels. The cells create a bottleneck that deprives tissues of oxygen and causes pain. The cells die more quickly than normal red blood cells, leaving the body chronically short of such cells and anemic. About one in 12 African Americans is a carrier.
Thalassemia is a term that covers a range of related anemias that vary in severity. A baby with thalassemia major may appear normal during the first year but subsequently develops symptoms such as jaundice (yellowed skin) and low appetite. If untreated, enlargement of the liver and spleen can occur, sometimes leading to heart failure or heightened susceptibility to life-threatening infections.
Von Hippel-Lindau disease (VHL) is a rare, genetic multi-system disorder characterized by the abnormal growth of tumors in certain parts of the body (angiomatosis). The tumors of the central nervous system (CNS) are benign and are comprised of a nest of blood vessels and are called hemangioblastomas (or angiomas in the eye). Hemangioblastomas may develop in the brain, the retina of the eyes, and other areas of the nervous system. Other types of tumors develop in the adrenal glands, the kidneys or the pancreas. Gene testing is available.
Recessive Genetic Conditions More Prevalent in Individuals of Ashkenazi Jewish Descent
Canavan disease is a neurodegenerative disease characterized by lack of the aspartoacylase enzyme, which is critical for central nervous system development and function. The progression is similar to Tay-Sachs disease, and affected children usually die by age five. Your doctor, even an ob/gyn, may not be aware of the risk for Canavan disease. The carrier rate is about one in 40 among Ashkenazi Jews.
Congenital deafness can be caused by one of two changes in a gene called Connexin 26. About one in 21 individuals of Ashkenazi Jewish descent has one of the two mutations.
Colon Cancer
Are You A Candidate For Colon Cancer Testing?
If your family has a history of colorectal and related cancers, you may want to consider genetic testing for mutations in two genes strongly associated with a hereditary nonpolyposis colon cancer (HNPCC). The syndrome increases lifetime risk of colorectal cancer to 80 percent vs. a two percent population risk, but also boosts your risk of endometrial cancer (to 60 percent), ovarian cancer (to 12 percent) and gastric cancer (to 13 percent). Those with HNPCC also face a higher risk of cancers of the kidney and ureter, gallbladder, central nervous system and small bowel.
To determine whether testing might be appropriate for your family, a genetic counselor would look for incidence of these cancers in two or more family members at a young age (under 50), or incidence of two types of cancer in one family member at a young age. Testing is also an option if you have two first-degree relatives (parents, siblings or children) diagnosed with one of these cancers at any age.
Many aspects of the testing parallel BRCA testing. The ideal initial candidate is a person who has been diagnosed with cancer, and the initial test runs about $2,000 with subsequent tests for other family members costing about $300.
Preventive options for those who test positive include:
Annual colonoscopies beginning in the early to mid-20s
Annual screening for endometrial cancer using transvaginal ultrasound and/or endometrial aspirate beginning in the 20s
Prophylactic surgery to remove the colon (rarely recommended), the uterus and/or the ovaries
Genetic counseling is vital at every step to help educate you to make the best choices for yourself and your family.
There are also tests available for mutations associated with a rarer colon cancer syndrome called familial adenomatous polyposis, which is typified by a very early age of onset (the teens) and appearance of many polyps.
If your family has a history of colorectal and related cancers, you may want to consider genetic testing for mutations in two genes strongly associated with a hereditary nonpolyposis colon cancer (HNPCC). The syndrome increases lifetime risk of colorectal cancer to 80 percent vs. a two percent population risk, but also boosts your risk of endometrial cancer (to 60 percent), ovarian cancer (to 12 percent) and gastric cancer (to 13 percent). Those with HNPCC also face a higher risk of cancers of the kidney and ureter, gallbladder, central nervous system and small bowel.
To determine whether testing might be appropriate for your family, a genetic counselor would look for incidence of these cancers in two or more family members at a young age (under 50), or incidence of two types of cancer in one family member at a young age. Testing is also an option if you have two first-degree relatives (parents, siblings or children) diagnosed with one of these cancers at any age.
Many aspects of the testing parallel BRCA testing. The ideal initial candidate is a person who has been diagnosed with cancer, and the initial test runs about $2,000 with subsequent tests for other family members costing about $300.
Preventive options for those who test positive include:
Annual colonoscopies beginning in the early to mid-20s
Annual screening for endometrial cancer using transvaginal ultrasound and/or endometrial aspirate beginning in the 20s
Prophylactic surgery to remove the colon (rarely recommended), the uterus and/or the ovaries
Genetic counseling is vital at every step to help educate you to make the best choices for yourself and your family.
There are also tests available for mutations associated with a rarer colon cancer syndrome called familial adenomatous polyposis, which is typified by a very early age of onset (the teens) and appearance of many polyps.
BRCA Testing
You might be a candidate for BRCA testing if your family has:
Two or more members with breast and/or ovarian cancer. Note that the evidence of a mutation is just as strong if your mother has breast cancer and your sister has ovarian cancer as it would be if both had breast cancer. And because ovarian cancer is much rarer than breast cancer, two such cases are even more suggestive of an inherited mutation.
A relative whose cancer was diagnosed at a young age (under 50). Multiple incidences of early-onset breast or ovarian cancer are the No. 1 tip-off that a BRCA1/2 mutation might be lurking in the family. About three-fourths of breast cancers are diagnosed after menopause, so a younger age of onset serves as a good red flag.
An incidence of breast and ovarian cancer in the same woman, or two separate primary breast cancers in the same woman.
Your ethnic background may come into play with breast cancer risk as well, if you are of Ashkenazi Jewish descent. Women with such a background are about 10 times more likely to have a mutation than women in the general population. If you are of Ashkenazi Jewish descent, you may also consider testing if one family member has been diagnosed with breast cancer before the age of 45. Testing looks for three specific mutations that account for 90 percent of the positive BRCA1/2 gene changes in this population. If the test comes up negative in the face of a strong family history, a comprehensive BRCA full-sequence analysis may be ordered.
As you think about your family history and any associated risk, be sure to look at your father's side, as well as your mother's. If women on his side of the family have a mutation, you face as much risk of inheriting it as you do of inheriting a maternal-side defect.
If you are not sure but think there's a possibility that your family has a hereditary cancer pattern, talk to a genetic counselor. Genetic testing for cancer predisposition is an individual choice for adults. Some women prefer not to get tested, and some young women prefer to wait.
Did You Test Positive?
If you test positive for a BRCA mutation, there are options for minimizing your cancer risk, but none of them reduce your risk to zero:
Stepped-up screening and prevention efforts. If you test positive, mammography is recommended starting at age 25 and repeated annually. You should do a breast self-exam once a month, at the same time of the month. If you're premenopausal, you may want to do it the week after menstruation. A clinical breast exam by a physician is also recommended every six months (instead of the usual once a year).
Chemoprevention, or taking medications to reduce your risk. Tamoxifen, a treatment for breast cancer, can cut breast cancer risk 50 percent in high-risk patients. Raloxifene, a similarly designed drug that is approved for preventing osteoporosis is also under study as a cancer-preventing agent. Oral contraceptives containing estrogen and progestin can cut ovarian cancer risk up to 60 percent.
Prophylactic surgery to remove the breasts (mastectomy) and/or ovaries (oophorectomy). This is the most radical option, but some women choose it because of the high lifetime risk of cancer that accompanies BRCA1/2 mutations.
Oophorectomy is increasingly being recommended for women who test positive for BRCA mutations and are either finished with childbearing or are certain that they do not want children. Removal of the ovaries not only reduces ovarian cancer risk 90 to 95 percent, it also reduces breast cancer risk 50 percent. That's because the ovaries produce estrogen, which stimulates breast growth and is linked to cancer risk. The bad news is that removing the ovaries also removes your body's source of estrogen. Therefore, estrogen levels diminish rapidly and trigger menopausal symptoms, such as hot flashes, vaginal dryness and bone loss, among other short-term physical and emotional changes and long-term health risks associated with menopause. For some women, "surgical menopause," when one or more ovaries is removed, can trigger more sudden and severe menopausal symptoms than when menopause occurs spontaneously at the end of a woman's childbearing years-a transition that typically takes about five years in a woman's late 40s.
Postmenopausal hormone therapy (often referred to as hormone replacement therapy or HRT) can be prescribed prior to or just after surgery to mitigate menopausal symptoms. However, women, health care professionals, and the Federal government are scrutinizing the use of postmenopausal hormone therapy more closely than ever before and its safety for both long-term and short-term use is in question.
In January 2003, the U.S. Food and Drug Administration (FDA) announced that it would require a new, highlighted and boxed warning on all estrogen products for use by postmenopausal women. The so-called "black box" is the strongest step the FDA can take to warn consumers of potential risks from a medication. The warning highlights the increased risk for heart disease, heart attacks, stroke and breast cancer from supplemental estrogen-risks illuminated by part of the Women's Health Initiative study, which was abruptly halted in July 2002 when the risks were identified.
The "black-box" warning also advises health care professionals to prescribe estrogen products at the lowest dose and for the shortest possible length of time. Women taking estrogen products are cautioned to have yearly breast exams, perform monthly breast self-exams and receive periodic mammograms.
Because every woman's risk profile is different, women who are thinking about taking postmenopausal hormone therapy or are currently taking it for whatever reason, need to review their options and treatment plans with their health care professional in light of the FDA's recent warning.
New, lower-dose versions of the hormone therapies used to treat symptoms of menopause are currently being developed. The FDA recently approved a low-dose version of the combination estrogen-progestin treatment sold as Prempro, which is expected to be available in the summer of 2003.
Families with hereditary cancers may choose to participate in research studies and familial cancer registries. This option helps researchers identify new cancer-associated genes and ultimately may aid the design of better cancer therapies. Registries and research are typically housed at the nation's leading cancer centers, so participation can also provide better access to top-quality, cutting-edge care. Participants give informed consent and their privacy is protected.
Two or more members with breast and/or ovarian cancer. Note that the evidence of a mutation is just as strong if your mother has breast cancer and your sister has ovarian cancer as it would be if both had breast cancer. And because ovarian cancer is much rarer than breast cancer, two such cases are even more suggestive of an inherited mutation.
A relative whose cancer was diagnosed at a young age (under 50). Multiple incidences of early-onset breast or ovarian cancer are the No. 1 tip-off that a BRCA1/2 mutation might be lurking in the family. About three-fourths of breast cancers are diagnosed after menopause, so a younger age of onset serves as a good red flag.
An incidence of breast and ovarian cancer in the same woman, or two separate primary breast cancers in the same woman.
Your ethnic background may come into play with breast cancer risk as well, if you are of Ashkenazi Jewish descent. Women with such a background are about 10 times more likely to have a mutation than women in the general population. If you are of Ashkenazi Jewish descent, you may also consider testing if one family member has been diagnosed with breast cancer before the age of 45. Testing looks for three specific mutations that account for 90 percent of the positive BRCA1/2 gene changes in this population. If the test comes up negative in the face of a strong family history, a comprehensive BRCA full-sequence analysis may be ordered.
As you think about your family history and any associated risk, be sure to look at your father's side, as well as your mother's. If women on his side of the family have a mutation, you face as much risk of inheriting it as you do of inheriting a maternal-side defect.
If you are not sure but think there's a possibility that your family has a hereditary cancer pattern, talk to a genetic counselor. Genetic testing for cancer predisposition is an individual choice for adults. Some women prefer not to get tested, and some young women prefer to wait.
Did You Test Positive?
If you test positive for a BRCA mutation, there are options for minimizing your cancer risk, but none of them reduce your risk to zero:
Stepped-up screening and prevention efforts. If you test positive, mammography is recommended starting at age 25 and repeated annually. You should do a breast self-exam once a month, at the same time of the month. If you're premenopausal, you may want to do it the week after menstruation. A clinical breast exam by a physician is also recommended every six months (instead of the usual once a year).
Chemoprevention, or taking medications to reduce your risk. Tamoxifen, a treatment for breast cancer, can cut breast cancer risk 50 percent in high-risk patients. Raloxifene, a similarly designed drug that is approved for preventing osteoporosis is also under study as a cancer-preventing agent. Oral contraceptives containing estrogen and progestin can cut ovarian cancer risk up to 60 percent.
Prophylactic surgery to remove the breasts (mastectomy) and/or ovaries (oophorectomy). This is the most radical option, but some women choose it because of the high lifetime risk of cancer that accompanies BRCA1/2 mutations.
Oophorectomy is increasingly being recommended for women who test positive for BRCA mutations and are either finished with childbearing or are certain that they do not want children. Removal of the ovaries not only reduces ovarian cancer risk 90 to 95 percent, it also reduces breast cancer risk 50 percent. That's because the ovaries produce estrogen, which stimulates breast growth and is linked to cancer risk. The bad news is that removing the ovaries also removes your body's source of estrogen. Therefore, estrogen levels diminish rapidly and trigger menopausal symptoms, such as hot flashes, vaginal dryness and bone loss, among other short-term physical and emotional changes and long-term health risks associated with menopause. For some women, "surgical menopause," when one or more ovaries is removed, can trigger more sudden and severe menopausal symptoms than when menopause occurs spontaneously at the end of a woman's childbearing years-a transition that typically takes about five years in a woman's late 40s.
Postmenopausal hormone therapy (often referred to as hormone replacement therapy or HRT) can be prescribed prior to or just after surgery to mitigate menopausal symptoms. However, women, health care professionals, and the Federal government are scrutinizing the use of postmenopausal hormone therapy more closely than ever before and its safety for both long-term and short-term use is in question.
In January 2003, the U.S. Food and Drug Administration (FDA) announced that it would require a new, highlighted and boxed warning on all estrogen products for use by postmenopausal women. The so-called "black box" is the strongest step the FDA can take to warn consumers of potential risks from a medication. The warning highlights the increased risk for heart disease, heart attacks, stroke and breast cancer from supplemental estrogen-risks illuminated by part of the Women's Health Initiative study, which was abruptly halted in July 2002 when the risks were identified.
The "black-box" warning also advises health care professionals to prescribe estrogen products at the lowest dose and for the shortest possible length of time. Women taking estrogen products are cautioned to have yearly breast exams, perform monthly breast self-exams and receive periodic mammograms.
Because every woman's risk profile is different, women who are thinking about taking postmenopausal hormone therapy or are currently taking it for whatever reason, need to review their options and treatment plans with their health care professional in light of the FDA's recent warning.
New, lower-dose versions of the hormone therapies used to treat symptoms of menopause are currently being developed. The FDA recently approved a low-dose version of the combination estrogen-progestin treatment sold as Prempro, which is expected to be available in the summer of 2003.
Families with hereditary cancers may choose to participate in research studies and familial cancer registries. This option helps researchers identify new cancer-associated genes and ultimately may aid the design of better cancer therapies. Registries and research are typically housed at the nation's leading cancer centers, so participation can also provide better access to top-quality, cutting-edge care. Participants give informed consent and their privacy is protected.
Breast Cancer
Are You A Candidate For Breast Cancer Testing?
Because breast cancer is one of the most common cancers, the test women are most often asking about is the one for BRCA mutations. A Salt Lake City-based company called Myriad Genetics has patented the BRCA genes and performs genetic testing. The lab testing is complex, but all that is needed from you is a blood sample.
It is important to remember that even when a family has a mutation, not everyone will inherit it. You have two copies of every gene. If one of your father's two copies of, say, BRCA1, has a mutation, your chance of inheriting that mutation is 50 percent. Thus, in a group of siblings, some will inherit a mutation, others won't. If your sister has breast cancer and you don't, she's the better candidate for testing, because if you test negative for a mutation, it may mean there's no mutation in the family, or may simply mean you didn't happen to inherit it. The result gives no guidance for the rest of your family.
An initial comprehensive analysis of BRCA1 and BRCA2 costs $2,580; if a mutation is identified in the first person tested, subsequent tests for other family members are $295 each. The reason the first test is so expensive is that the genes must be fully sequenced to identify the mutation. Once a mutation is found, the technicians know where exactly to look in the other relatives' DNA samples. A variation of the test that looks only at three specific mutations found in the Ashkenazi Jewish population (Eastern European background) is $350.
If no one in your family has been diagnosed with breast or ovarian cancer, then your risk of carrying a BRCA1/2 mutation is very small and testing would not be recommended. Keep in mind, however, that absence of these mutations doesn't mean you won't develop cancer. At least 90 percent of breast and ovarian cancer cases are "sporadic," meaning they don't stem from inherited mutations, but rather are caused by a mutation, or combination of mutations that arise over time. Therefore, regardless of your genetic status, be sure to take precautions such as having a once-yearly breast examination by your health care professional (called a clinical breast examination) and a mammogram, if appropriate (schedule based on age).
Because breast cancer is one of the most common cancers, the test women are most often asking about is the one for BRCA mutations. A Salt Lake City-based company called Myriad Genetics has patented the BRCA genes and performs genetic testing. The lab testing is complex, but all that is needed from you is a blood sample.
It is important to remember that even when a family has a mutation, not everyone will inherit it. You have two copies of every gene. If one of your father's two copies of, say, BRCA1, has a mutation, your chance of inheriting that mutation is 50 percent. Thus, in a group of siblings, some will inherit a mutation, others won't. If your sister has breast cancer and you don't, she's the better candidate for testing, because if you test negative for a mutation, it may mean there's no mutation in the family, or may simply mean you didn't happen to inherit it. The result gives no guidance for the rest of your family.
An initial comprehensive analysis of BRCA1 and BRCA2 costs $2,580; if a mutation is identified in the first person tested, subsequent tests for other family members are $295 each. The reason the first test is so expensive is that the genes must be fully sequenced to identify the mutation. Once a mutation is found, the technicians know where exactly to look in the other relatives' DNA samples. A variation of the test that looks only at three specific mutations found in the Ashkenazi Jewish population (Eastern European background) is $350.
If no one in your family has been diagnosed with breast or ovarian cancer, then your risk of carrying a BRCA1/2 mutation is very small and testing would not be recommended. Keep in mind, however, that absence of these mutations doesn't mean you won't develop cancer. At least 90 percent of breast and ovarian cancer cases are "sporadic," meaning they don't stem from inherited mutations, but rather are caused by a mutation, or combination of mutations that arise over time. Therefore, regardless of your genetic status, be sure to take precautions such as having a once-yearly breast examination by your health care professional (called a clinical breast examination) and a mammogram, if appropriate (schedule based on age).
Inherited Cancer
Testing for Inherited Cancer
If you have a family history of cancer, particularly cancers that occur before age 50, you may want to explore genetic counseling to determine if an inherited gene mutation could be responsible. Hereditary cancers are not always obvious. A mutation that leads to breast cancer in your grandmother may lead to ovarian cancer in your aunt. Likewise, a mutation that causes colon cancer in your sister may cause endometrial cancer in your daughter.
To determine whether your family's cancers might be hereditary in nature, a genetic counselor will need to know medical details about the family, especially those who have been diagnosed with cancer. Age of diagnosis and the exact diagnosis is the most important factors; be prepared for a counselor to request medical records. Also be prepared for several possible conclusions about your family history:
The cancers in the family, even if there are several, may be "sporadic" and not linked to an inherited genetic defect.
The pattern fits a known hereditary cancer syndrome for which genetic testing is available. Those who test positive for the mutation would need to be vigilant about prevention and screening measures.
Family history suggests an inherited pattern, but one that fits no currently characterized syndrome. Everyone who may have inherited the apparent predisposition to cancer should pursue stepped-up prevention and screening efforts.
Some inherited cancer syndromes for which testing is available are
Hereditary breast and ovarian cancer syndrome, caused by mutations in the BRCA1 or BRCA2 genes, often referred to as the "breast cancer genes."
Hereditary non-polyposis colon cancer, caused by mutations in the MLH1 and MSH2, genes. Such mutations are also linked to cancers of the endometrium, stomach, small bowel, ureter, ovary and collecting system of the kidneys.
Familial adenomatous polyposis, caused by a mutation in the APC gene that leads to the growth of hundreds or thousands of polyps in the colon beginning as early as the teenage years.
Ataxia telangiectasia, a complex disorder caused by a mutation in the ATM gene. Among other effects, including dysfunction of the cerebellum (the part of the brain that controls motor function and balance), A-T has been linked to lymphomas and leukemia. This autosomal recessive disorder is diagnosed in childhood. As individuals live longer, other cancers have been observed, including ovarian and breast cancers, stomach cancer and melanoma.
Multiple endocrine neoplasia 1 and 2 are two separate rare disorders caused by mutations in the MEN1 or RET genes, respectively; MEN1 or 2 can lead to cancer in one of the endocrine glands, such as the parathyroid, thyroid, pancreas, pituitary or adrenal gland.
Researchers also suspect a hereditary component to some cases of prostate and lung cancer, but as yet have not identified gene mutations for testing.
The genes themselves don't cause cancer. The problem comes when they are not functioning normally. You were born with two copies of each of these genes, one inherited from your mother and one from your father. In some cases, if you inherit a mutation in one of these genes, you will not immediately develop cancer, because you have a backup functioning gene. But over time, the unaffected gene may become damaged in one cell, allowing that cell to become cancerous and multiply.
Such an outcome is common among individuals with an inherited mutation linked to breast cancer or colon cancer. Those with a BRCA mutation face a lifetime breast cancer risk of up to 85 percent, compared to about 12.5 percent in the general population, and a lifetime ovarian cancer risk of up to 44 percent, compared to a population risk of about one percent.
A positive result from a genetic test does not mean you will definitely develop one of these cancers, only that your risk is much higher than that of individuals without a mutation. And a negative test result certainly does not mean you won't develop cancer. In fact, only one out of 10 cases of breast cancer involves an inherited mutation, and only five to 10 percent of colon cancers are hereditary.
The knowledge that you are positive for a mutation allows you to take action to reduce your risk through preventive measures, such as more frequent screening to detect early growths or tumors, taking protective medications, or even prophylactic surgery to remove the organ prone to cancer.
If you have a family history of cancer, particularly cancers that occur before age 50, you may want to explore genetic counseling to determine if an inherited gene mutation could be responsible. Hereditary cancers are not always obvious. A mutation that leads to breast cancer in your grandmother may lead to ovarian cancer in your aunt. Likewise, a mutation that causes colon cancer in your sister may cause endometrial cancer in your daughter.
To determine whether your family's cancers might be hereditary in nature, a genetic counselor will need to know medical details about the family, especially those who have been diagnosed with cancer. Age of diagnosis and the exact diagnosis is the most important factors; be prepared for a counselor to request medical records. Also be prepared for several possible conclusions about your family history:
The cancers in the family, even if there are several, may be "sporadic" and not linked to an inherited genetic defect.
The pattern fits a known hereditary cancer syndrome for which genetic testing is available. Those who test positive for the mutation would need to be vigilant about prevention and screening measures.
Family history suggests an inherited pattern, but one that fits no currently characterized syndrome. Everyone who may have inherited the apparent predisposition to cancer should pursue stepped-up prevention and screening efforts.
Some inherited cancer syndromes for which testing is available are
Hereditary breast and ovarian cancer syndrome, caused by mutations in the BRCA1 or BRCA2 genes, often referred to as the "breast cancer genes."
Hereditary non-polyposis colon cancer, caused by mutations in the MLH1 and MSH2, genes. Such mutations are also linked to cancers of the endometrium, stomach, small bowel, ureter, ovary and collecting system of the kidneys.
Familial adenomatous polyposis, caused by a mutation in the APC gene that leads to the growth of hundreds or thousands of polyps in the colon beginning as early as the teenage years.
Ataxia telangiectasia, a complex disorder caused by a mutation in the ATM gene. Among other effects, including dysfunction of the cerebellum (the part of the brain that controls motor function and balance), A-T has been linked to lymphomas and leukemia. This autosomal recessive disorder is diagnosed in childhood. As individuals live longer, other cancers have been observed, including ovarian and breast cancers, stomach cancer and melanoma.
Multiple endocrine neoplasia 1 and 2 are two separate rare disorders caused by mutations in the MEN1 or RET genes, respectively; MEN1 or 2 can lead to cancer in one of the endocrine glands, such as the parathyroid, thyroid, pancreas, pituitary or adrenal gland.
Researchers also suspect a hereditary component to some cases of prostate and lung cancer, but as yet have not identified gene mutations for testing.
The genes themselves don't cause cancer. The problem comes when they are not functioning normally. You were born with two copies of each of these genes, one inherited from your mother and one from your father. In some cases, if you inherit a mutation in one of these genes, you will not immediately develop cancer, because you have a backup functioning gene. But over time, the unaffected gene may become damaged in one cell, allowing that cell to become cancerous and multiply.
Such an outcome is common among individuals with an inherited mutation linked to breast cancer or colon cancer. Those with a BRCA mutation face a lifetime breast cancer risk of up to 85 percent, compared to about 12.5 percent in the general population, and a lifetime ovarian cancer risk of up to 44 percent, compared to a population risk of about one percent.
A positive result from a genetic test does not mean you will definitely develop one of these cancers, only that your risk is much higher than that of individuals without a mutation. And a negative test result certainly does not mean you won't develop cancer. In fact, only one out of 10 cases of breast cancer involves an inherited mutation, and only five to 10 percent of colon cancers are hereditary.
The knowledge that you are positive for a mutation allows you to take action to reduce your risk through preventive measures, such as more frequent screening to detect early growths or tumors, taking protective medications, or even prophylactic surgery to remove the organ prone to cancer.
Carrier Screening
Carrier Screening
You could be carrying a genetic mutation for a debilitating disease such as cystic fibrosis, sickle cell disease or Tay-Sachs disease and not even know it. That's because carriers of these mutations have no symptoms-in fact, they don't even have the disease.
Genes come in matched pairs, except for those on the sex chromosomes. In the case of autosomal recessive disorders such as these, if only one of these matched genes is damaged, there's no problem. The unaffected gene does the job. In fact, a disease-causing mutation can run through dozens of generations of a family without ever making itself known.
But if two carriers of the same gene change have a child, their chance of passing on what genetic counselors sometimes call a "double whammy"-two defective genes-is 25 percent. Of course, their chance of passing on two unaffected genes is also 25 percent, and the chance that a child will be a healthy carrier (with one normal gene and one defective one, but not afflicted with the disease) is 50 percent.
The exception to this pattern occurs if a disorder is recessive and X-linked. The X is the symbol for the larger sex chromosome. A child who inherits two X chromosomes is a girl. A child with an X chromosome and a Y chromosome is a boy. If a mother has a disease-linked recessive mutation on one of her X chromosomes, she is a carrier of the disorder but should have no or minimal symptoms herself. If she has a son, he will have a 50 percent risk of inheriting the disorder because he has no backup X chromosome; a daughter will have a 50 percent chance of being a carrier, like her mother.
Fragile X syndrome, as its name suggests, is one such X-linked disorder. Boys who inherit the mutation usually develop the disease, the most common form of genetically inherited mental retardation. Girls who inherit a fragile X mutation are more likely to be carriers. (The gene is unstable and the mutation tends to increase in size over succeeding generations, so that girls may eventually be affected as well, though the mental retardation is not usually as severe as it is in boys.) All affected individuals are related through females, as the fragile X gene "grows" only in the egg. If you have a family history of mental retardation, testing can determine whether a fragile X mutation is responsible and whether you are a carrier.
As with other types of testing, genetic counseling can help you understand carrier screenings. A counselor can also help you develop strategies for sharing the information with other family members who may also be at risk of carrying the mutation.
Carrier screening is recommended for any disorder that has surfaced in your family, either by virtue of a relative developing the disease or testing positive as a carrier. However, you should also consider screening for mutations found frequently in your particular ethnic group. The prevalence of genetic disorders is linked closely to ethnic heritage. Caucasians, for example, have a much higher risk than most other groups for cystic fibrosis, and those of African American descent are more likely to be carriers of sickle cell anemia mutations.
Many carrier screening tests are relatively inexpensive (usually $50 to $75 per individual screen) because they don't require sequencing of an entire gene. Instead they zero in on mutations known to be common in particular groups. The results are generally very accurate (95 percent or higher) and straightforward: A person is either a carrier or not.
Below is a list linking various groups to genetic disorders they are more likely to inherit:
Caucasians: phenylketonuria, hemochromatosis, cystic fibrosis, alpha 1-antitrypsin deficiency, celiac disease (no genetic test available, but physicians can test blood to measure levels of antibodies to gluten. These antibodies are antigliadin, anti-endomysium, and antireticulin.)
African Americans: sickle cell disease and Thalassemia
East Asians (except Koreans): Thalassemia
Irish, French Canadians and Cajuns: Tay-Sachs disease
Mediterraneans: thalassemia, celiac disease, and familial Mediterranean fever
Southeast Asians (Cambodians, Laotians and Vietnamese): hemoglobinopathies (disorders of hemoglobin, the oxygen-carrying component of red blood cells)
There is also a battery of tests for mutations found more often in the Ashkenazi Jewish population. The Ashkenazi are Jews of Central and East European descent, and they account for some 80 percent of the Jewish population in the United States.
The carrier screening tests for Ashkenazi Jews varies from program to program. Some test only for Tay-Sachs and Canavan diseases; some include many other disorders, such as Gaucher disease, Bloom syndrome, Fanconi anemia, Niemann-Pick disease and hereditary deafness. If you use insurance to pay for testing, you may have to use a particular center and test panel. Testing for Familial Dysautonomia is now available, too.
Many panels also include a screen for cystic fibrosis (CF). This condition is not more common in the Ashkenazi population. Caucasians are actually more likely to carry CF mutations than other groups. Still, the ratio of the Ashkenazi population that carries known CF mutations is fairly high, about one in 29. Three specific mutations are common in this population, making testing more specific.
People of Ashkenazi Jewish origin are, of course, no more likely to have a genetic disorder than other populations; they have been the focus of much genetics research because the population remained relatively isolated and small for centuries.
Experts Recommend Preconception Screening
You might think that if you and your partner come from different backgrounds, carrier screening is unnecessary. The American College of Obstetricians and Gynecologists, however, advises that if one partner in a couple is at high risk and the other is not, the high-risk partner should be screened. If that person tests positive as a carrier the other partner should be screened.
Genetics experts recommend carrier screening in young adulthood or before a marriage-and definitely before a couple tries to conceive. But you may have to be proactive in seeking the testing. If you live in a region where there aren't many members of your ethnic group, a local physician may not be well informed about the issues.
If two prospective parents are found to be carriers of a disease, their options include:
Adoption
use of donor sperm or a donor egg
in vitro fertilization and preimplantation genetic testing of the embryos (an expensive process)
prenatal testing (with the option of an abortion if the fetus has two copies of a debilitating mutation)
For some diseases, the outcome of having two mutated genes is variable from patient to patient. Someone with a particular disease mutation, for example, may not have symptoms until middle age, or may go a lifetime asymptomatic, making decisions about testing-and what to do if a fetus turns out to be affected-difficult for prospective parents
You could be carrying a genetic mutation for a debilitating disease such as cystic fibrosis, sickle cell disease or Tay-Sachs disease and not even know it. That's because carriers of these mutations have no symptoms-in fact, they don't even have the disease.
Genes come in matched pairs, except for those on the sex chromosomes. In the case of autosomal recessive disorders such as these, if only one of these matched genes is damaged, there's no problem. The unaffected gene does the job. In fact, a disease-causing mutation can run through dozens of generations of a family without ever making itself known.
But if two carriers of the same gene change have a child, their chance of passing on what genetic counselors sometimes call a "double whammy"-two defective genes-is 25 percent. Of course, their chance of passing on two unaffected genes is also 25 percent, and the chance that a child will be a healthy carrier (with one normal gene and one defective one, but not afflicted with the disease) is 50 percent.
The exception to this pattern occurs if a disorder is recessive and X-linked. The X is the symbol for the larger sex chromosome. A child who inherits two X chromosomes is a girl. A child with an X chromosome and a Y chromosome is a boy. If a mother has a disease-linked recessive mutation on one of her X chromosomes, she is a carrier of the disorder but should have no or minimal symptoms herself. If she has a son, he will have a 50 percent risk of inheriting the disorder because he has no backup X chromosome; a daughter will have a 50 percent chance of being a carrier, like her mother.
Fragile X syndrome, as its name suggests, is one such X-linked disorder. Boys who inherit the mutation usually develop the disease, the most common form of genetically inherited mental retardation. Girls who inherit a fragile X mutation are more likely to be carriers. (The gene is unstable and the mutation tends to increase in size over succeeding generations, so that girls may eventually be affected as well, though the mental retardation is not usually as severe as it is in boys.) All affected individuals are related through females, as the fragile X gene "grows" only in the egg. If you have a family history of mental retardation, testing can determine whether a fragile X mutation is responsible and whether you are a carrier.
As with other types of testing, genetic counseling can help you understand carrier screenings. A counselor can also help you develop strategies for sharing the information with other family members who may also be at risk of carrying the mutation.
Carrier screening is recommended for any disorder that has surfaced in your family, either by virtue of a relative developing the disease or testing positive as a carrier. However, you should also consider screening for mutations found frequently in your particular ethnic group. The prevalence of genetic disorders is linked closely to ethnic heritage. Caucasians, for example, have a much higher risk than most other groups for cystic fibrosis, and those of African American descent are more likely to be carriers of sickle cell anemia mutations.
Many carrier screening tests are relatively inexpensive (usually $50 to $75 per individual screen) because they don't require sequencing of an entire gene. Instead they zero in on mutations known to be common in particular groups. The results are generally very accurate (95 percent or higher) and straightforward: A person is either a carrier or not.
Below is a list linking various groups to genetic disorders they are more likely to inherit:
Caucasians: phenylketonuria, hemochromatosis, cystic fibrosis, alpha 1-antitrypsin deficiency, celiac disease (no genetic test available, but physicians can test blood to measure levels of antibodies to gluten. These antibodies are antigliadin, anti-endomysium, and antireticulin.)
African Americans: sickle cell disease and Thalassemia
East Asians (except Koreans): Thalassemia
Irish, French Canadians and Cajuns: Tay-Sachs disease
Mediterraneans: thalassemia, celiac disease, and familial Mediterranean fever
Southeast Asians (Cambodians, Laotians and Vietnamese): hemoglobinopathies (disorders of hemoglobin, the oxygen-carrying component of red blood cells)
There is also a battery of tests for mutations found more often in the Ashkenazi Jewish population. The Ashkenazi are Jews of Central and East European descent, and they account for some 80 percent of the Jewish population in the United States.
The carrier screening tests for Ashkenazi Jews varies from program to program. Some test only for Tay-Sachs and Canavan diseases; some include many other disorders, such as Gaucher disease, Bloom syndrome, Fanconi anemia, Niemann-Pick disease and hereditary deafness. If you use insurance to pay for testing, you may have to use a particular center and test panel. Testing for Familial Dysautonomia is now available, too.
Many panels also include a screen for cystic fibrosis (CF). This condition is not more common in the Ashkenazi population. Caucasians are actually more likely to carry CF mutations than other groups. Still, the ratio of the Ashkenazi population that carries known CF mutations is fairly high, about one in 29. Three specific mutations are common in this population, making testing more specific.
People of Ashkenazi Jewish origin are, of course, no more likely to have a genetic disorder than other populations; they have been the focus of much genetics research because the population remained relatively isolated and small for centuries.
Experts Recommend Preconception Screening
You might think that if you and your partner come from different backgrounds, carrier screening is unnecessary. The American College of Obstetricians and Gynecologists, however, advises that if one partner in a couple is at high risk and the other is not, the high-risk partner should be screened. If that person tests positive as a carrier the other partner should be screened.
Genetics experts recommend carrier screening in young adulthood or before a marriage-and definitely before a couple tries to conceive. But you may have to be proactive in seeking the testing. If you live in a region where there aren't many members of your ethnic group, a local physician may not be well informed about the issues.
If two prospective parents are found to be carriers of a disease, their options include:
Adoption
use of donor sperm or a donor egg
in vitro fertilization and preimplantation genetic testing of the embryos (an expensive process)
prenatal testing (with the option of an abortion if the fetus has two copies of a debilitating mutation)
For some diseases, the outcome of having two mutated genes is variable from patient to patient. Someone with a particular disease mutation, for example, may not have symptoms until middle age, or may go a lifetime asymptomatic, making decisions about testing-and what to do if a fetus turns out to be affected-difficult for prospective parents
Prental
Prenatal Testing
Prenatal testing to detect chromosomal defects and inherited genetic disorders has been widely available for women with high-risk pregnancies since the 1970s. These days nearly every pregnant woman in the U.S. has a preliminary maternal serum screening test performed.
The serum test, a simple blood test, is usually performed between week 15 and week 18 of the pregnancy (as measured from the start of the most recent menstrual period). The test evaluates your risk of having a baby with:
An open neural tube defect. When the neural tube fails to close, the baby is born with an opening in the head (anencephaly) or spinal cord (spina bifida). Babies with anencephaly are stillborn or die soon after birth; those with spina bifida need surgery and may be paralyzed.
Down syndrome (also called Trisomy 21). An extra copy of chromosome 21 causes Down syndrome, characterized by mental retardation, certain facial features and sometimes heart defects.
Trisomy 18. An extra copy of chromosome 18 causes this syndrome, which usually proves fatal during the first year of the baby's life and is associated with severe mental retardation.
The blood screen does not look directly at genetic material but instead measures three substances-alpha-fetoprotein, unconjugated estriol and human chorionic gonadotropin-to determine whether you are at increased risk of having a baby with one of these disorders. A key fact to remember is that this test does not diagnose the disorders-it only screens for the substances. Further testing is always suggested to make a diagnosis.
Indeed, most of the time, the fetus is not affected with the disorder even if the screening result is abnormal. According to Genzyme Genetics, a genetics laboratory based in Framingham, Mass, out of 1,000 serum screening tests, 25 will suggest an increased risk for open neural tube defects, but only one or two of the fetuses will have such a defect. Likewise 70 out of 1,000 will test positive for increased risk of Down syndrome, but only one or two fetuses will actually have the condition.
Most labs offer the standard "triple marker" serum screening test, which picks up about 70 percent of Down syndrome cases among women under 35, and 85 to 90 percent in women 35 and older. A recently introduced four-marker test incorporating a measure for a chemical called inhibin-A improves detection rates for Down syndrome by five to 10 percentage points. Some centers also offer first trimester screening to determine if a woman is at increased risk for having a baby with Down syndrome or trisomy 18. The test has two parts and both should both be performed between the 10th and 13 weeks of gestation. One part tests levels of maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in the mother's blood. The other measures the nuchal thickening (measure of fetal neck thickness) through a specialized ultrasound. This test detects more than 90 percent of fetuses with Down syndrome and approximately 97 percent with Trisomy 18. However, it is a screening test and still requires a confirmatory chorionic villous sampling or amniocentesis to make the definite diagnosis.
A screening test does not diagnose a problem. It should not be used to make either treatment decisions or decisions to terminate a pregnancy, but rather should be used to determine appropriate next steps.
Prenatal testing to detect chromosomal defects and inherited genetic disorders has been widely available for women with high-risk pregnancies since the 1970s. These days nearly every pregnant woman in the U.S. has a preliminary maternal serum screening test performed.
The serum test, a simple blood test, is usually performed between week 15 and week 18 of the pregnancy (as measured from the start of the most recent menstrual period). The test evaluates your risk of having a baby with:
An open neural tube defect. When the neural tube fails to close, the baby is born with an opening in the head (anencephaly) or spinal cord (spina bifida). Babies with anencephaly are stillborn or die soon after birth; those with spina bifida need surgery and may be paralyzed.
Down syndrome (also called Trisomy 21). An extra copy of chromosome 21 causes Down syndrome, characterized by mental retardation, certain facial features and sometimes heart defects.
Trisomy 18. An extra copy of chromosome 18 causes this syndrome, which usually proves fatal during the first year of the baby's life and is associated with severe mental retardation.
The blood screen does not look directly at genetic material but instead measures three substances-alpha-fetoprotein, unconjugated estriol and human chorionic gonadotropin-to determine whether you are at increased risk of having a baby with one of these disorders. A key fact to remember is that this test does not diagnose the disorders-it only screens for the substances. Further testing is always suggested to make a diagnosis.
Indeed, most of the time, the fetus is not affected with the disorder even if the screening result is abnormal. According to Genzyme Genetics, a genetics laboratory based in Framingham, Mass, out of 1,000 serum screening tests, 25 will suggest an increased risk for open neural tube defects, but only one or two of the fetuses will have such a defect. Likewise 70 out of 1,000 will test positive for increased risk of Down syndrome, but only one or two fetuses will actually have the condition.
Most labs offer the standard "triple marker" serum screening test, which picks up about 70 percent of Down syndrome cases among women under 35, and 85 to 90 percent in women 35 and older. A recently introduced four-marker test incorporating a measure for a chemical called inhibin-A improves detection rates for Down syndrome by five to 10 percentage points. Some centers also offer first trimester screening to determine if a woman is at increased risk for having a baby with Down syndrome or trisomy 18. The test has two parts and both should both be performed between the 10th and 13 weeks of gestation. One part tests levels of maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in the mother's blood. The other measures the nuchal thickening (measure of fetal neck thickness) through a specialized ultrasound. This test detects more than 90 percent of fetuses with Down syndrome and approximately 97 percent with Trisomy 18. However, it is a screening test and still requires a confirmatory chorionic villous sampling or amniocentesis to make the definite diagnosis.
A screening test does not diagnose a problem. It should not be used to make either treatment decisions or decisions to terminate a pregnancy, but rather should be used to determine appropriate next steps.
Genetic Counseling
What is Genetic Counseling?
Because the nature of genetic testing is so complex, with implications for both the person being tested and his or her family, counseling is desirable before taking any genetic test and essential if results come back positive or uncertain. Unlike most medical appointments, a counseling session may be a family affair, with participation of all concerned relatives. Counselors say sometimes a dozen or more relatives attend.
A genetic counselor is a health care professional who is an expert in counseling, genetics and genetic testing. She (most today are women) reviews your family history to determine if there appears to be a hereditary pattern of disease and who might be affected. A genetic counseling session usually lasts at least an hour and includes:
gathering background information on your family and the disease under discussion
providing information on inheritance, the genetic testing procedure, the possible results and what they mean
Testing usually is not performed at the first counseling session, and there is never any pressure to take a test. Genetic counseling will educate you so you can make an informed decision. If you are feeling ambivalent, counseling won't push you in one direction or the other, but it can help you decide whether testing is right for you.
Because family history is so crucial to deciding whether testing has a chance of identifying a disease-linked mutation, a counselor may request medical records to confirm a diagnosis, especially if you're trying to determine whether a family pattern of cancer is hereditary.
Family member recollections can be inaccurate-who had which disease or even what type of disease. Many conditions either were not discussed or not diagnosed in past decades. A genetic counselor will listen to a family account and help tease out details to better identify potential patterns.
Many women never think about genetic testing until they are considering having a child or have become pregnant. Prenatal testing offers an opportunity to test for chromosomal and common genetic disorders, as well as genetic conditions that have surfaced on either side of the family or for which either parent is a carrier. Counselors recommend a preconception session to discuss carrier testing and prenatal testing options.
Privacy Concerns
Genetic counselors are committed to protecting your privacy. They will not contact other family members without your permission, though they may encourage you to share results that might affect your relatives. Many counseling centers will store records of test results separate from your main medical record to help keep the information out of the hands of insurers and employers, unless you give permission to share. (Of course, if you use insurance to pay for testing, the company will have access to your file.) If you are concerned about your privacy, ask your genetic counselor about the center's policy. Thus far, experts say, there has been little evidence of insurer or employer discrimination based on genetic testing, but that may change once such testing becomes commonplace.
Genetic Testing And Children
Up to age 18, genetic tests are used only for diagnosing conditions for which the proper care during childhood or adolescence can make a difference, not for doing carrier screening or testing for diseases that may affect children later in life (presymptomatic testing).
Newborn screening programs are now idely available for genetic diseases treatable early in life. Such a test can indicate elevated risk of a disorder, and a positive result should be followed up with further diagnostics. Below are the most commonly administered newborn screening tests, though remember that not every state administers every test (check with a health care professional to find out):
Phenylketonuria (PKU) is characterized by an inability to metabolize an amino acid called phenylalanine and causes mental retardation unless a specialized phenylalanine-free diet is put in place. Aspartame (Equal) should be avoided if you have PKU.
Hypothyroidism can interfere with growth and mental development if not treated.
Galactosemia can cause mental retardation if not treated with a diet free of a sugar called galactose, which is found in dairy products.
Sickle cell disease makes a baby more susceptible to infection but early treatment with penicillin reduces the risk.
Newborn screening programs designed to test for 30 conditions are now being introduced in some hospitals. If this type of program is not available at your hospital, you can obtain your own kit by mail and have your baby tested at the hospital or your pediatrician's office.
Because the nature of genetic testing is so complex, with implications for both the person being tested and his or her family, counseling is desirable before taking any genetic test and essential if results come back positive or uncertain. Unlike most medical appointments, a counseling session may be a family affair, with participation of all concerned relatives. Counselors say sometimes a dozen or more relatives attend.
A genetic counselor is a health care professional who is an expert in counseling, genetics and genetic testing. She (most today are women) reviews your family history to determine if there appears to be a hereditary pattern of disease and who might be affected. A genetic counseling session usually lasts at least an hour and includes:
gathering background information on your family and the disease under discussion
providing information on inheritance, the genetic testing procedure, the possible results and what they mean
Testing usually is not performed at the first counseling session, and there is never any pressure to take a test. Genetic counseling will educate you so you can make an informed decision. If you are feeling ambivalent, counseling won't push you in one direction or the other, but it can help you decide whether testing is right for you.
Because family history is so crucial to deciding whether testing has a chance of identifying a disease-linked mutation, a counselor may request medical records to confirm a diagnosis, especially if you're trying to determine whether a family pattern of cancer is hereditary.
Family member recollections can be inaccurate-who had which disease or even what type of disease. Many conditions either were not discussed or not diagnosed in past decades. A genetic counselor will listen to a family account and help tease out details to better identify potential patterns.
Many women never think about genetic testing until they are considering having a child or have become pregnant. Prenatal testing offers an opportunity to test for chromosomal and common genetic disorders, as well as genetic conditions that have surfaced on either side of the family or for which either parent is a carrier. Counselors recommend a preconception session to discuss carrier testing and prenatal testing options.
Privacy Concerns
Genetic counselors are committed to protecting your privacy. They will not contact other family members without your permission, though they may encourage you to share results that might affect your relatives. Many counseling centers will store records of test results separate from your main medical record to help keep the information out of the hands of insurers and employers, unless you give permission to share. (Of course, if you use insurance to pay for testing, the company will have access to your file.) If you are concerned about your privacy, ask your genetic counselor about the center's policy. Thus far, experts say, there has been little evidence of insurer or employer discrimination based on genetic testing, but that may change once such testing becomes commonplace.
Genetic Testing And Children
Up to age 18, genetic tests are used only for diagnosing conditions for which the proper care during childhood or adolescence can make a difference, not for doing carrier screening or testing for diseases that may affect children later in life (presymptomatic testing).
Newborn screening programs are now idely available for genetic diseases treatable early in life. Such a test can indicate elevated risk of a disorder, and a positive result should be followed up with further diagnostics. Below are the most commonly administered newborn screening tests, though remember that not every state administers every test (check with a health care professional to find out):
Phenylketonuria (PKU) is characterized by an inability to metabolize an amino acid called phenylalanine and causes mental retardation unless a specialized phenylalanine-free diet is put in place. Aspartame (Equal) should be avoided if you have PKU.
Hypothyroidism can interfere with growth and mental development if not treated.
Galactosemia can cause mental retardation if not treated with a diet free of a sugar called galactose, which is found in dairy products.
Sickle cell disease makes a baby more susceptible to infection but early treatment with penicillin reduces the risk.
Newborn screening programs designed to test for 30 conditions are now being introduced in some hospitals. If this type of program is not available at your hospital, you can obtain your own kit by mail and have your baby tested at the hospital or your pediatrician's office.
Genetic Testing
Genetic Testing
Today, there are hundreds of different genetic tests, some of them for relatively common disorders, such as cystic fibrosis, and some for very rare diseases. A genetic test is fundamentally different from other kinds of diagnostic tests you might take. Indeed, a whole new field, genetic counseling, has grown up around the need to help patients understand the testing process.
The purposes of genetic tests vary. Some tests are used to confirm a preliminary diagnosis based on symptoms. But other genetic tests measure your risk of developing a disease, even if you are healthy now (presymptomatic testing), or whether you and your partner are at risk of having a child with a genetic disorder (carrier screening).
As the name suggests, a genetic test looks at your genes, which consist of DNA (deoxyribonucleic acid). Each gene contains a chemical message to produce a protein, which has a specific function in the body. Proteins are essential to life-they serve as building blocks for cells and tissues; they produce energy and act as messengers to make your body function. In addition to studying genes, genetic testing in a broader sense includes biochemical tests for the presence or absence of key proteins that signal aberrant gene function.
Some tests look at chromosomes for abnormalities such as an extra chromosome, or an incomplete or missing chromosome. Sometimes, pieces of chromosomes become switched, or transposed, so that a gene ends up in a location where it is permanently and inappropriately turned on or off. Chromosomes are made up of DNA with long chains of genes mixed with inactive DNA. Each of us has 46 chromosomes in the nucleus of each cell, half contributed by each parent. The genes on the chromosomes are responsible for directing our biological development and the activity of about 100 trillion cells in our bodies.
If something goes wrong with an essential protein, the consequences can be severe. For example, a protein called alpha-1 antitrypsin (AAT) clears the lungs of a caustic agent called neutrophil elastase. Those who cannot manufacture AAT because of a defect in the gene that produces the protein often develop emphysema and other complications.
Most genetic conditions come in the form of a mutation in a gene that alters the instructions for making the proteins. These mutations can lead to diseases ranging from those we think of as "genetic diseases," such as cystic fibrosis or AAT deficiency, to those we think of as degenerative diseases, such as cancer and heart disease. In the case of diseases like cancer, heart disease, asthma or diabetes, a combination of factors-some genetic, some related to environmental or lifestyle factors-may work together to trigger the disease.
It's possible to have a mutation, even one for a severe disease, such as cystic fibrosis (CF) and never even know it. That's because genes come in pairs-one contributed by your mother, one from your father. If you have a single such mutation, you are a healthy carrier of the disorder. Such disorders are called autosomal recessive. The unaltered gene in the pair retains the function. The disease becomes a possibility only if two carriers of the same recessive gene have a child. Each child of two carriers of the same disorder has a 25 percent chance of inheriting the disease. It is equally likely (a 25 percent chance) that both parents will contribute their unaltered genes, only the mutated genes, thus there is a 50 percent chance that the child will receive one functioning gene and one mutated gene-in other words, a 50 percent chance that the child will be a healthy carrier like the parents.
Some disorders, such as Huntington disease, are autosomal dominant. If a person has one mutated gene, its effects will cause the disease, even if the matching gene is normal. Thus, each child of a parent with Huntington disease has a 50 percent chance of inheriting the disease. Osteogenesis imperfecta, which causes brittle bones, is another example of a dominant disorder.
Autosomal means the gene is not found on one of the two sex chromosomes, X and Y. If each parent contributes an X chromosome, the child is a girl; an X and a Y chromosome makes the child a boy. Because girls have two copies of every sex-linked gene, they are less likely to have symptoms from X-linked genetic diseases than boys, who don't have a backup copy if an X-chromosome gene is mutated. Examples of X-linked diseases include forms of hemophilia and fragile X syndrome (the most common inherited cause of mental impairment).
Sometimes a genetic defect simply increases risk of developing a disease, often in conjunction with other genetic or environmental factors. For example, a mutation in a BRCA gene increases your risk of breast or ovarian cancer, but only if the companion unmutated copy of the gene in the same cell also acquires a mutation.
A normal copy of BRCA in a breast cell might acquire a mutation due to exposure to, say, an environmental toxin or radiation, or it might become mutated through a sporadic "mistake" during cell division and DNA replication. For a woman without a mutation, it would take two such events in one cell to trigger a BRCA-related breast cancer; for the woman who inherits a BRCA mutation, it takes only one. Other genes can also play a role. A woman with a BRCA mutation who also has a p53 (tumor suppressor gene) mutation would also be more vulnerable, and no doubt there are other genes whose malfunctioning in combination with a BRCA mutation can trigger breast cancer.
There also are other risk factors for breast cancer, such as high alcohol intake (more than two drinks per day), being overweight, not having children or having an early onset of menses.
Most women who develop breast cancer have no known risks for developing the disease other than being a woman or, in the case of an older woman, age. Age is a risk factor for developing many types of cancer.
An increased risk does not necessarily mean you have a disease or will develop it. Genetic test results can yield information to help you and your health care professionals better manage your health, or, in the case of prenatal testing, your baby's care.
Unfortunately, though, genetic tests do not always provide the clear answers you may want. Sometimes a mutation is found that is of uncertain significance. Also, many tests are designed to look for the most common disease-causing mutations. If you or your family has a unique mutation, these tests won't pick it up. Hence, many of the tests boast detection rates of 95 percent or more, but they are not perfect. If you have a strong family history of a disease and uncertain or negative test results, it may be better to play it safe and take added prevention measures as if you had tested positive for the mutation. A genetic counselor can provide guidance.
The Cost of Genetic Testing
The cost of a genetic test varies dramatically, ranging from about $50 to upwards of $2,000. The difference stems largely from the variation in labor intensity of different tests. Some tests look for a limited number of mutations (sometimes only one) known to cause a disease; others require sequencing of the entire gene. It's the difference between looking at a few particular frames of a film for defects and examining the entire reel.
The explosion of genetic research now taking place is expected to bring prices down and dramatically increase the number of tests available. In the coming years, tests may be available to predict your genetic risk of developing heart disease or diabetes, for example, and will help you and your health care professional develop specific strategies for prevention. Preventive efforts can include changing your lifestyle or perhaps taking certain medications, which may be tailored to your specific genetic profile, and early screening to head off the worst complications should you develop the disease.
Today, there are hundreds of different genetic tests, some of them for relatively common disorders, such as cystic fibrosis, and some for very rare diseases. A genetic test is fundamentally different from other kinds of diagnostic tests you might take. Indeed, a whole new field, genetic counseling, has grown up around the need to help patients understand the testing process.
The purposes of genetic tests vary. Some tests are used to confirm a preliminary diagnosis based on symptoms. But other genetic tests measure your risk of developing a disease, even if you are healthy now (presymptomatic testing), or whether you and your partner are at risk of having a child with a genetic disorder (carrier screening).
As the name suggests, a genetic test looks at your genes, which consist of DNA (deoxyribonucleic acid). Each gene contains a chemical message to produce a protein, which has a specific function in the body. Proteins are essential to life-they serve as building blocks for cells and tissues; they produce energy and act as messengers to make your body function. In addition to studying genes, genetic testing in a broader sense includes biochemical tests for the presence or absence of key proteins that signal aberrant gene function.
Some tests look at chromosomes for abnormalities such as an extra chromosome, or an incomplete or missing chromosome. Sometimes, pieces of chromosomes become switched, or transposed, so that a gene ends up in a location where it is permanently and inappropriately turned on or off. Chromosomes are made up of DNA with long chains of genes mixed with inactive DNA. Each of us has 46 chromosomes in the nucleus of each cell, half contributed by each parent. The genes on the chromosomes are responsible for directing our biological development and the activity of about 100 trillion cells in our bodies.
If something goes wrong with an essential protein, the consequences can be severe. For example, a protein called alpha-1 antitrypsin (AAT) clears the lungs of a caustic agent called neutrophil elastase. Those who cannot manufacture AAT because of a defect in the gene that produces the protein often develop emphysema and other complications.
Most genetic conditions come in the form of a mutation in a gene that alters the instructions for making the proteins. These mutations can lead to diseases ranging from those we think of as "genetic diseases," such as cystic fibrosis or AAT deficiency, to those we think of as degenerative diseases, such as cancer and heart disease. In the case of diseases like cancer, heart disease, asthma or diabetes, a combination of factors-some genetic, some related to environmental or lifestyle factors-may work together to trigger the disease.
It's possible to have a mutation, even one for a severe disease, such as cystic fibrosis (CF) and never even know it. That's because genes come in pairs-one contributed by your mother, one from your father. If you have a single such mutation, you are a healthy carrier of the disorder. Such disorders are called autosomal recessive. The unaltered gene in the pair retains the function. The disease becomes a possibility only if two carriers of the same recessive gene have a child. Each child of two carriers of the same disorder has a 25 percent chance of inheriting the disease. It is equally likely (a 25 percent chance) that both parents will contribute their unaltered genes, only the mutated genes, thus there is a 50 percent chance that the child will receive one functioning gene and one mutated gene-in other words, a 50 percent chance that the child will be a healthy carrier like the parents.
Some disorders, such as Huntington disease, are autosomal dominant. If a person has one mutated gene, its effects will cause the disease, even if the matching gene is normal. Thus, each child of a parent with Huntington disease has a 50 percent chance of inheriting the disease. Osteogenesis imperfecta, which causes brittle bones, is another example of a dominant disorder.
Autosomal means the gene is not found on one of the two sex chromosomes, X and Y. If each parent contributes an X chromosome, the child is a girl; an X and a Y chromosome makes the child a boy. Because girls have two copies of every sex-linked gene, they are less likely to have symptoms from X-linked genetic diseases than boys, who don't have a backup copy if an X-chromosome gene is mutated. Examples of X-linked diseases include forms of hemophilia and fragile X syndrome (the most common inherited cause of mental impairment).
Sometimes a genetic defect simply increases risk of developing a disease, often in conjunction with other genetic or environmental factors. For example, a mutation in a BRCA gene increases your risk of breast or ovarian cancer, but only if the companion unmutated copy of the gene in the same cell also acquires a mutation.
A normal copy of BRCA in a breast cell might acquire a mutation due to exposure to, say, an environmental toxin or radiation, or it might become mutated through a sporadic "mistake" during cell division and DNA replication. For a woman without a mutation, it would take two such events in one cell to trigger a BRCA-related breast cancer; for the woman who inherits a BRCA mutation, it takes only one. Other genes can also play a role. A woman with a BRCA mutation who also has a p53 (tumor suppressor gene) mutation would also be more vulnerable, and no doubt there are other genes whose malfunctioning in combination with a BRCA mutation can trigger breast cancer.
There also are other risk factors for breast cancer, such as high alcohol intake (more than two drinks per day), being overweight, not having children or having an early onset of menses.
Most women who develop breast cancer have no known risks for developing the disease other than being a woman or, in the case of an older woman, age. Age is a risk factor for developing many types of cancer.
An increased risk does not necessarily mean you have a disease or will develop it. Genetic test results can yield information to help you and your health care professionals better manage your health, or, in the case of prenatal testing, your baby's care.
Unfortunately, though, genetic tests do not always provide the clear answers you may want. Sometimes a mutation is found that is of uncertain significance. Also, many tests are designed to look for the most common disease-causing mutations. If you or your family has a unique mutation, these tests won't pick it up. Hence, many of the tests boast detection rates of 95 percent or more, but they are not perfect. If you have a strong family history of a disease and uncertain or negative test results, it may be better to play it safe and take added prevention measures as if you had tested positive for the mutation. A genetic counselor can provide guidance.
The Cost of Genetic Testing
The cost of a genetic test varies dramatically, ranging from about $50 to upwards of $2,000. The difference stems largely from the variation in labor intensity of different tests. Some tests look for a limited number of mutations (sometimes only one) known to cause a disease; others require sequencing of the entire gene. It's the difference between looking at a few particular frames of a film for defects and examining the entire reel.
The explosion of genetic research now taking place is expected to bring prices down and dramatically increase the number of tests available. In the coming years, tests may be available to predict your genetic risk of developing heart disease or diabetes, for example, and will help you and your health care professional develop specific strategies for prevention. Preventive efforts can include changing your lifestyle or perhaps taking certain medications, which may be tailored to your specific genetic profile, and early screening to head off the worst complications should you develop the disease.
Fibroids
Fibroids
Fibroids are masses of muscular tissue that can develop within the wall of the uterus. They are the most common noncancerous tumor in premenopausal women. You may hear your health care professional call fibroids by other terms, including uterine leiomyomas, fibromyomas, fibromas, myofibromas and myomas. They can be small or quite large.
While fibroids can cause a variety of symptoms, they may not cause any symptoms at all—so you may not even know you have one. Heavy bleeding is the most common symptom associated with fibroids and the one that usually prompts a woman to make an appointment with her health care professional. You may learn you have one or more fibroids after having a pelvic exam.
Fibroids may cause a range of other symptoms, too, including pain, pressure in the pelvic region, abnormal bleeding, painful intercourse, frequent urination or infertility.
What actually causes fibroids to form isn't clear, but genetics and hormones are thought to play a big role. Your body may be predisposed to developing fibroids. They seem to grow or shrink depending on estrogen levels in your body, but researchers don't know why some women develop them while others don't.
Fibroids usually grow slowly during your reproductive years, but may increase in size with pregnancy. At menopause fibroids shrink because estrogen levels decline. Using menopausal hormone therapy containing estrogen after menopause may cause fibroids to continue to grow and cause symptoms.
Progesterone, growth hormone and prolactin are other hormones that may stimulate a fibroid's growth once it has already formed.
A variety of treatments exist to remove fibroids and relieve symptoms. If you learn you have fibroids, but you aren't experiencing symptoms, you usually won't need treatment.
Who is at risk for fibroids?
Your risk for developing fibroids increases with age. African-American women are at least twice as likely as Caucasian women to have them. If women in your family have already been diagnosed with fibroids, you have an increased risk of developing them. Obesity and high blood pressure also contribute to your risk of developing fibroids, but if you take oral contraceptives or have given birth your risk decreases.
Types of Fibroids
Fibroids form in different parts of the uter:
Submucosal fibroids grow from the uterine wall into the uterine cavity. They can cause pain, abnormal bleeding and infertility.
Subserosal fibroids grow from the uterine wall to the outside of the uterus. They can push on the bladder, bowel or intestine causing bloating, abdominal pressure, cramping and pain.
Intramural fibroids are confined within the muscle wall of the uterus, and are the most common fibroid type. They can cause symptoms similar to those caused by fibroids in other parts of the uterus.
Pendunculated. These fibroids grow on stalks out from the uterus or into the uterine cavity, like mushrooms. If these stalks twist, they can cause pain, nausea or fever, or can become infected.
Fibroids are masses of muscular tissue that can develop within the wall of the uterus. They are the most common noncancerous tumor in premenopausal women. You may hear your health care professional call fibroids by other terms, including uterine leiomyomas, fibromyomas, fibromas, myofibromas and myomas. They can be small or quite large.
While fibroids can cause a variety of symptoms, they may not cause any symptoms at all—so you may not even know you have one. Heavy bleeding is the most common symptom associated with fibroids and the one that usually prompts a woman to make an appointment with her health care professional. You may learn you have one or more fibroids after having a pelvic exam.
Fibroids may cause a range of other symptoms, too, including pain, pressure in the pelvic region, abnormal bleeding, painful intercourse, frequent urination or infertility.
What actually causes fibroids to form isn't clear, but genetics and hormones are thought to play a big role. Your body may be predisposed to developing fibroids. They seem to grow or shrink depending on estrogen levels in your body, but researchers don't know why some women develop them while others don't.
Fibroids usually grow slowly during your reproductive years, but may increase in size with pregnancy. At menopause fibroids shrink because estrogen levels decline. Using menopausal hormone therapy containing estrogen after menopause may cause fibroids to continue to grow and cause symptoms.
Progesterone, growth hormone and prolactin are other hormones that may stimulate a fibroid's growth once it has already formed.
A variety of treatments exist to remove fibroids and relieve symptoms. If you learn you have fibroids, but you aren't experiencing symptoms, you usually won't need treatment.
Who is at risk for fibroids?
Your risk for developing fibroids increases with age. African-American women are at least twice as likely as Caucasian women to have them. If women in your family have already been diagnosed with fibroids, you have an increased risk of developing them. Obesity and high blood pressure also contribute to your risk of developing fibroids, but if you take oral contraceptives or have given birth your risk decreases.
Types of Fibroids
Fibroids form in different parts of the uter:
Submucosal fibroids grow from the uterine wall into the uterine cavity. They can cause pain, abnormal bleeding and infertility.
Subserosal fibroids grow from the uterine wall to the outside of the uterus. They can push on the bladder, bowel or intestine causing bloating, abdominal pressure, cramping and pain.
Intramural fibroids are confined within the muscle wall of the uterus, and are the most common fibroid type. They can cause symptoms similar to those caused by fibroids in other parts of the uterus.
Pendunculated. These fibroids grow on stalks out from the uterus or into the uterine cavity, like mushrooms. If these stalks twist, they can cause pain, nausea or fever, or can become infected.
Roles of Estrogen
Other Roles of Estrogen
Bone
Estrogen produced by the ovaries helps prevent bone loss and works together with calcium and other hormones and minerals to build bones. Osteoporosis occurs when bones become too weak and brittle to support normal activities.
Your body constantly builds and remodels bone through a process called resorption and deposition. Up until around age 30, your body makes more new bone than it breaks down. But once estrogen levels start to decline, this process also slows.
Thus, after menopause your body breaks down more bone than it rebuilds. In the years immediately after menopause, women may lose as much as 20 percent of their bone mass. Although the rate of bone loss eventually levels out after menopause, keeping bone structures strong and healthy to prevent osteoporosis becomes more of a challenge.
Vagina and Urinary Tract
When estrogen levels are low, as in menopause, the vagina can become drier and the vaginal walls thinner, making sex painful.
Additionally, the lining of the urethra, the tube that brings urine from the bladder to the outside of the body, thins. A small number of women may experience an increase in urinary tract infections (UTIs) that can be improved with the use of vaginal estrogen therapy.
Perimenopause: The Menopause Transition
Other physical and emotional changes are associated with fluctuating estrogen levels during the transition to menopause and the year after menopause occurs, called perimenopause. This phase typically lasts about five years for most women. Symptoms include:
Hot flashes -- a sudden sensation of heat in your face, neck and chest that may cause you to sweat profusely, increase your pulse rate and make you feel dizzy or nauseous. A hot flash typically lasts about three to six minutes, although the sensation can last longer and may disrupt sleep when they occur at night.
Irregular menstrual cycles
Breast tenderness
Exacerbation of migraines
Urinary stress incontinence
Mood swings
Estrogen Therapy
Estrogen therapy is used to treat certain conditions, such as delayed onset of puberty and menopausal symptoms such as hot flashes and symptomatic vaginal atrophy. Vaginal atrophy is a condition in which low estrogen levels cause a woman's vagina to narrow, lose flexibility and take longer to lubricate. Female hypogonadism or incomplete functioning of the ovaries, can also cause vaginal dryness, breast atrophy and lower sex drive, and is also treated with estrogen.
For many years, estrogen therapy and estrogen-progestin therapy were prescribed to treat menopausal symptoms, to prevent osteoporosis and to improve women's overall health. However, after publication of results from the Women's Health Initiative (WHI) in July 2002 and March 2004, the U.S. Food and Drug Administration (FDA) now advises health care professionals to prescribe menopausal hormone therapies at the lowest possible dose and for the shortest possible length of time to achieve treatment goals.
The WHI was a study of 27,000 women aged 50-79 taking estrogen therapy or estrogen/progesterone therapy who was followed for an average of five to six years. The study was unable to document that benefits outweighed risks when hormone therapy was used as preventive therapy.
Determining hormone status can be important in certain settings. For instance, estrogen and other hormones are prescribed to treat reproductive health and endocrine disorders (the endocrine system is the system in the body that regulates hormone production and function).
Some uses of hormone therapy include the following situations:
Delayed puberty
Contraception
Irregular menstrual cycles
Symptomatic menopause
Bone
Estrogen produced by the ovaries helps prevent bone loss and works together with calcium and other hormones and minerals to build bones. Osteoporosis occurs when bones become too weak and brittle to support normal activities.
Your body constantly builds and remodels bone through a process called resorption and deposition. Up until around age 30, your body makes more new bone than it breaks down. But once estrogen levels start to decline, this process also slows.
Thus, after menopause your body breaks down more bone than it rebuilds. In the years immediately after menopause, women may lose as much as 20 percent of their bone mass. Although the rate of bone loss eventually levels out after menopause, keeping bone structures strong and healthy to prevent osteoporosis becomes more of a challenge.
Vagina and Urinary Tract
When estrogen levels are low, as in menopause, the vagina can become drier and the vaginal walls thinner, making sex painful.
Additionally, the lining of the urethra, the tube that brings urine from the bladder to the outside of the body, thins. A small number of women may experience an increase in urinary tract infections (UTIs) that can be improved with the use of vaginal estrogen therapy.
Perimenopause: The Menopause Transition
Other physical and emotional changes are associated with fluctuating estrogen levels during the transition to menopause and the year after menopause occurs, called perimenopause. This phase typically lasts about five years for most women. Symptoms include:
Hot flashes -- a sudden sensation of heat in your face, neck and chest that may cause you to sweat profusely, increase your pulse rate and make you feel dizzy or nauseous. A hot flash typically lasts about three to six minutes, although the sensation can last longer and may disrupt sleep when they occur at night.
Irregular menstrual cycles
Breast tenderness
Exacerbation of migraines
Urinary stress incontinence
Mood swings
Estrogen Therapy
Estrogen therapy is used to treat certain conditions, such as delayed onset of puberty and menopausal symptoms such as hot flashes and symptomatic vaginal atrophy. Vaginal atrophy is a condition in which low estrogen levels cause a woman's vagina to narrow, lose flexibility and take longer to lubricate. Female hypogonadism or incomplete functioning of the ovaries, can also cause vaginal dryness, breast atrophy and lower sex drive, and is also treated with estrogen.
For many years, estrogen therapy and estrogen-progestin therapy were prescribed to treat menopausal symptoms, to prevent osteoporosis and to improve women's overall health. However, after publication of results from the Women's Health Initiative (WHI) in July 2002 and March 2004, the U.S. Food and Drug Administration (FDA) now advises health care professionals to prescribe menopausal hormone therapies at the lowest possible dose and for the shortest possible length of time to achieve treatment goals.
The WHI was a study of 27,000 women aged 50-79 taking estrogen therapy or estrogen/progesterone therapy who was followed for an average of five to six years. The study was unable to document that benefits outweighed risks when hormone therapy was used as preventive therapy.
Determining hormone status can be important in certain settings. For instance, estrogen and other hormones are prescribed to treat reproductive health and endocrine disorders (the endocrine system is the system in the body that regulates hormone production and function).
Some uses of hormone therapy include the following situations:
Delayed puberty
Contraception
Irregular menstrual cycles
Symptomatic menopause
Estrogen
Estrogen
Estrogen is probably the most widely known and discussed of all hormones. The term "estrogen" actually refers to any of a group of chemically similar hormones; estrogenic hormones are sometimes mistakenly referred to as exclusively female hormones when in fact both men and women produce them. However, the role estrogen plays in men not entirely clear.
In order to understand the role estrogens play in women, it is important to understand something about hormones in general. Hormones are vital chemical substances in humans and animals. Often referred to as "chemical messengers," hormones carry information and instructions from one group of cells to another. In the human body, hormones influence almost every cell, organ and function. They regulate our growth, development, tissue function, sexual function, the way our bodies use food, the reaction of our bodies to emergencies, and even our moods.
The estrogenic hormones are uniquely responsible for the growth and development of female sexual characteristics and reproduction in both humans and animals. The term "estrogen" includes a group of chemically similar hormones: estrone, estradiol (the most abundant) and estriol. Overall, estrogen is produced in the ovaries, adrenal glands and fat tissues. More specifically, the estradiol and estrone forms are produced in the ovaries, while estriol is produced by the placenta during pregnancy.
In women, estrogen circulates in the bloodstream and binds to estrogen receptors on cells in targeted tissues, affecting not only the breast and uterus, but also the brain, bone, liver, heart and other tissues.
Estrogen controls growth of the uterine lining during the first part of the menstrual cycle, causes changes in the breasts during adolescence and pregnancy, and regulates various other metabolic processes, including bone growth and cholesterol levels.
During the reproductive years, the pituitary gland in the brain generates hormones that cause a new egg to be released from its follicle each month. As the follicle develops, it produces estrogen, which causes the lining of the uterus to thicken.
Progesterone production increases after ovulation in the middle of a woman's cycle to prepare the lining to receive and nourish a fertilized egg so it can develop into a fetus. If fertilization does not occur, estrogen and progesterone levels drop sharply, the lining of the uterus breaks down and menstruation occurs.
If fertilization does occur, estrogen and progesterone work together to prevent additional ovulation during pregnancy. Birth control pills (oral contraceptives) take advantage of this effect by regulating hormone levels. They also result in the production of a very thin uterine lining, called the endometrium, which is unreceptive to a fertilized egg. Plus, they thicken the cervical mucus to prevent sperm from entering the cervix and fertilizing an egg.
Oral contraceptives containing estrogen may also relieve menstrual cramps and some perimenopausal symptoms, and regulate menstrual cycles in women with polycystic ovarian syndrome (PCOS). Furthermore, research indicates that birth control pills may reduce the risk of ovarian, uterine and colorectal cancer.
Estrogen is probably the most widely known and discussed of all hormones. The term "estrogen" actually refers to any of a group of chemically similar hormones; estrogenic hormones are sometimes mistakenly referred to as exclusively female hormones when in fact both men and women produce them. However, the role estrogen plays in men not entirely clear.
In order to understand the role estrogens play in women, it is important to understand something about hormones in general. Hormones are vital chemical substances in humans and animals. Often referred to as "chemical messengers," hormones carry information and instructions from one group of cells to another. In the human body, hormones influence almost every cell, organ and function. They regulate our growth, development, tissue function, sexual function, the way our bodies use food, the reaction of our bodies to emergencies, and even our moods.
The estrogenic hormones are uniquely responsible for the growth and development of female sexual characteristics and reproduction in both humans and animals. The term "estrogen" includes a group of chemically similar hormones: estrone, estradiol (the most abundant) and estriol. Overall, estrogen is produced in the ovaries, adrenal glands and fat tissues. More specifically, the estradiol and estrone forms are produced in the ovaries, while estriol is produced by the placenta during pregnancy.
In women, estrogen circulates in the bloodstream and binds to estrogen receptors on cells in targeted tissues, affecting not only the breast and uterus, but also the brain, bone, liver, heart and other tissues.
Estrogen controls growth of the uterine lining during the first part of the menstrual cycle, causes changes in the breasts during adolescence and pregnancy, and regulates various other metabolic processes, including bone growth and cholesterol levels.
During the reproductive years, the pituitary gland in the brain generates hormones that cause a new egg to be released from its follicle each month. As the follicle develops, it produces estrogen, which causes the lining of the uterus to thicken.
Progesterone production increases after ovulation in the middle of a woman's cycle to prepare the lining to receive and nourish a fertilized egg so it can develop into a fetus. If fertilization does not occur, estrogen and progesterone levels drop sharply, the lining of the uterus breaks down and menstruation occurs.
If fertilization does occur, estrogen and progesterone work together to prevent additional ovulation during pregnancy. Birth control pills (oral contraceptives) take advantage of this effect by regulating hormone levels. They also result in the production of a very thin uterine lining, called the endometrium, which is unreceptive to a fertilized egg. Plus, they thicken the cervical mucus to prevent sperm from entering the cervix and fertilizing an egg.
Oral contraceptives containing estrogen may also relieve menstrual cramps and some perimenopausal symptoms, and regulate menstrual cycles in women with polycystic ovarian syndrome (PCOS). Furthermore, research indicates that birth control pills may reduce the risk of ovarian, uterine and colorectal cancer.
Epilepsy Happens
Why Epilepsy Happens
As one of the first brain disorders described in ancient Babylon more than 3,000 years ago, epilepsy has been associated with many misconceptions over the years. Epilepsy is a disorder in which the normal pattern of brain activity becomes disturbed. During a seizure, neurons fire as many as 500 times a second, far exceeding the normal rate of about 80 times a second. The resulting seizure can occur at any time of the day or night with little to no warning. Some people have frequent attacks, but others seldom have them.
Genetic abnormalities may be the most significant factors that contribute to epilepsy. The condition may run in some families, and some researchers say that more than 500 genes could be linked to the disorder.
For many people, epilepsy is the result of brain injury from other conditions or disorders. Heart attacks and strokes, for example, deprive the brain of oxygen and can cause damage that can produce epilepsy. Conditions that affect the brain's normal workings, such as brain tumors, Alzheimer's disease and alcoholism, also may trigger it. Metabolic disorders such as pyruvate deficiency and other brain disorders such as cerebral palsy, neurofibromatosis and autism are all associated with an increased risk of epilepsy, as well.
Virtually any sort of injury to the brain, from head trauma to poisoning (such as from carbon monoxide or even illegal drug use) to infections can lead to seizures and epilepsy.
Other cases that involve neither brain damage, injury nor known genetic factors, and which have no known cause, are known as idiopathic epilepsy. The cause of epilepsy remains an active area of research.
Types of Seizure and Epilepsy: Many and Varied
To date, researchers have identified more than 20 different kinds of seizures and dozens of syndromes and other conditions that include recurring seizures. People can have one or more than one type of seizure. In general, there are two kinds of seizures:
Partial seizures. About 60 percent of people with epilepsy have partial seizures, which occur in just one part of the brain and affect the physical and mental activity controlled by that area of the brain. Partial seizures may also originate in multiple parts of the brain or start in one part of the brain and spread to the entire brain.
During a simple partial seizure, a woman can remain conscious and experience unexplained feelings or sensations. In a complex partial seizure (formerly called a psychomotor or temporal lobe seizure, a woman can experience an altered consciousness, display repetitious behavior or movements and not be able to interact with others until the seizure subsides. Emotional changes may also occur during the seizure. Complex partial seizures are the most common type of seizures in adults, although the condition typically begins in childhood. Repeated seizures in the temporal lobe of the brain can, over a long period of time, affect memory and learning.
Generalized seizures. There are many types of generalized seizures. Primary generalized seizures involve bursts of electrical energy that sweep through the whole brain at once, causing loss of consciousness for seconds or minutes, falls, convulsions or muscle spasms.
Absence seizures (formerly called petit mal seizures) are a common type of generalized seizure that typically start in childhood and typically stop when the child reaches puberty. During an absence seizure, a child may experience temporary lapses of consciousness that look like blank staring.
When seizures occur, a health care professional will determine if they are associated with epilepsy or another condition that can cause seizures. Determining the underlying cause is critical to effective and appropriate treatment. (See the Treatment section for more information.)
The many types of epilepsy are usually described by a specific group of symptoms. Some of the more common types include:
Frontal lobe epilepsy: Sudden onset and termination of a cluster of very short seizures are the hallmarks of this type of epilepsy.
Occipital lobe epilepsy: This type usually begins with visual hallucinations, rapid eye blinking or other eye-related symptoms: After that, it resembles temporal or frontal lobe epilepsy.
Temporal lobe epilepsy: This type may typically have a "warning" or aura of altered perceptions (déjà-vu, jamais vu) followed by altered awareness, confusion and responsiveness.
As one of the first brain disorders described in ancient Babylon more than 3,000 years ago, epilepsy has been associated with many misconceptions over the years. Epilepsy is a disorder in which the normal pattern of brain activity becomes disturbed. During a seizure, neurons fire as many as 500 times a second, far exceeding the normal rate of about 80 times a second. The resulting seizure can occur at any time of the day or night with little to no warning. Some people have frequent attacks, but others seldom have them.
Genetic abnormalities may be the most significant factors that contribute to epilepsy. The condition may run in some families, and some researchers say that more than 500 genes could be linked to the disorder.
For many people, epilepsy is the result of brain injury from other conditions or disorders. Heart attacks and strokes, for example, deprive the brain of oxygen and can cause damage that can produce epilepsy. Conditions that affect the brain's normal workings, such as brain tumors, Alzheimer's disease and alcoholism, also may trigger it. Metabolic disorders such as pyruvate deficiency and other brain disorders such as cerebral palsy, neurofibromatosis and autism are all associated with an increased risk of epilepsy, as well.
Virtually any sort of injury to the brain, from head trauma to poisoning (such as from carbon monoxide or even illegal drug use) to infections can lead to seizures and epilepsy.
Other cases that involve neither brain damage, injury nor known genetic factors, and which have no known cause, are known as idiopathic epilepsy. The cause of epilepsy remains an active area of research.
Types of Seizure and Epilepsy: Many and Varied
To date, researchers have identified more than 20 different kinds of seizures and dozens of syndromes and other conditions that include recurring seizures. People can have one or more than one type of seizure. In general, there are two kinds of seizures:
Partial seizures. About 60 percent of people with epilepsy have partial seizures, which occur in just one part of the brain and affect the physical and mental activity controlled by that area of the brain. Partial seizures may also originate in multiple parts of the brain or start in one part of the brain and spread to the entire brain.
During a simple partial seizure, a woman can remain conscious and experience unexplained feelings or sensations. In a complex partial seizure (formerly called a psychomotor or temporal lobe seizure, a woman can experience an altered consciousness, display repetitious behavior or movements and not be able to interact with others until the seizure subsides. Emotional changes may also occur during the seizure. Complex partial seizures are the most common type of seizures in adults, although the condition typically begins in childhood. Repeated seizures in the temporal lobe of the brain can, over a long period of time, affect memory and learning.
Generalized seizures. There are many types of generalized seizures. Primary generalized seizures involve bursts of electrical energy that sweep through the whole brain at once, causing loss of consciousness for seconds or minutes, falls, convulsions or muscle spasms.
Absence seizures (formerly called petit mal seizures) are a common type of generalized seizure that typically start in childhood and typically stop when the child reaches puberty. During an absence seizure, a child may experience temporary lapses of consciousness that look like blank staring.
When seizures occur, a health care professional will determine if they are associated with epilepsy or another condition that can cause seizures. Determining the underlying cause is critical to effective and appropriate treatment. (See the Treatment section for more information.)
The many types of epilepsy are usually described by a specific group of symptoms. Some of the more common types include:
Frontal lobe epilepsy: Sudden onset and termination of a cluster of very short seizures are the hallmarks of this type of epilepsy.
Occipital lobe epilepsy: This type usually begins with visual hallucinations, rapid eye blinking or other eye-related symptoms: After that, it resembles temporal or frontal lobe epilepsy.
Temporal lobe epilepsy: This type may typically have a "warning" or aura of altered perceptions (déjà-vu, jamais vu) followed by altered awareness, confusion and responsiveness.
Epilepsy
Epilepsy
In a healthy brain, nerve cells communicate with each other through electrical impulses that work together to control the body. But when those cells, called neurons, misfire or signal abnormally, a person can experience a number of sensations, emotions, behaviors, convulsions, muscle spasms and even loss of consciousness during what's called a seizure. If a person has more than one seizure, she may be suffering from epilepsy, a chronic health condition that can be managed but not always cured.
The symptoms of epilepsy are complex. A seizure can be as subtle as staring off into space for a few moments so that the person experiencing it appears to be daydreaming. Other types of seizures cause more dramatic symptoms, including uncontrollable movements, loss of consciousness and loss of some bodily functions, among other symptoms. These symptoms can be as brief as a few seconds or as long as several minutes.
According to the Epilepsy Foundation and the U.S. Centers for Disease Control and Prevention, some 181,000 Americans will learn that they have epilepsy this year, and an estimated 2.5 million are currently living with the disorder. Approximately half of these individuals are women. According to the Epilepsy Foundation, it was estimated that this neurological disease cost approximately $12.5 billion annually in medical costs and lost or reduced earnings and production.
Epilepsy is not contagious nor is it caused by mental illness or retardation. But for most people who suffer from this chronic condition, the stigma associated with it is enormous and affects just about every aspect of life. Family life, driving, employment, social interactions and self-image are just a few lifestyle considerations that confront people with epilepsy. Just the fear of having a seizure produces tremendous ongoing anxiety for some people -- a burden for even those whose seizures are generally well controlled with medication.
There is no single cause of epilepsy. Some of the known causes include:
injury to the brain before, during or after birth
infections that damage the brain
toxic substances that affect the brain
injury and lack of oxygen to the brain
disturbance in blood circulation to the brain (stroke and other vascular problems)
metabolism or nutritional imbalance
tumors of the brain
genetic or hereditary abnormalities
high fever
other degenerative diseases
malformation of the brain
Seizures can be triggered by a variety of things, such as lack of sleep, alcohol consumption or hormonal changes associated with the menstrual cycle. Although these triggers don't cause epilepsy, they can provoke seizures. Sleep deprivation is perhaps the most powerful trigger of all.
Epilepsy and Reproductive Health Issues.
Epilepsy is associated with many reproductive health issues for women. Reproductive hormones (estrogen and progesterone) can have a strong impact on the frequency and severity of seizures. Many women experience changes in their seizure patterns at times of hormonal fluctuations such as puberty, ovulation, at the beginning of menstruation, pregnancy and even at menopause. This hormone-seizure interaction makes each life stage-and sometimes each menstrual period-a unique challenge for the woman with epilepsy. Because seizures disrupt regions of the brain that regulate reproductive hormones, women who have seizures also are more likely to have reproductive problems such as polycystic ovarian disease, early menopause and irregular ovulation.Even birth control choices are affected by epilepsy. Certain antiepileptic medications (medications that control seizures) make hormonal birth control less effective in preventing pregnancy. Hormonal birth control includes oral contraceptives (birth control pills), long acting progestin shots and implants and intrauterine devices that release hormones. While most women with epilepsy can have healthy babies, they are advised to work with health care professionals knowledgeable about seizure disorders to guard against increased risks for complications during pregnancy. See the Treatment section of this topic for more information on epilepsy and pregnancy
In a healthy brain, nerve cells communicate with each other through electrical impulses that work together to control the body. But when those cells, called neurons, misfire or signal abnormally, a person can experience a number of sensations, emotions, behaviors, convulsions, muscle spasms and even loss of consciousness during what's called a seizure. If a person has more than one seizure, she may be suffering from epilepsy, a chronic health condition that can be managed but not always cured.
The symptoms of epilepsy are complex. A seizure can be as subtle as staring off into space for a few moments so that the person experiencing it appears to be daydreaming. Other types of seizures cause more dramatic symptoms, including uncontrollable movements, loss of consciousness and loss of some bodily functions, among other symptoms. These symptoms can be as brief as a few seconds or as long as several minutes.
According to the Epilepsy Foundation and the U.S. Centers for Disease Control and Prevention, some 181,000 Americans will learn that they have epilepsy this year, and an estimated 2.5 million are currently living with the disorder. Approximately half of these individuals are women. According to the Epilepsy Foundation, it was estimated that this neurological disease cost approximately $12.5 billion annually in medical costs and lost or reduced earnings and production.
Epilepsy is not contagious nor is it caused by mental illness or retardation. But for most people who suffer from this chronic condition, the stigma associated with it is enormous and affects just about every aspect of life. Family life, driving, employment, social interactions and self-image are just a few lifestyle considerations that confront people with epilepsy. Just the fear of having a seizure produces tremendous ongoing anxiety for some people -- a burden for even those whose seizures are generally well controlled with medication.
There is no single cause of epilepsy. Some of the known causes include:
injury to the brain before, during or after birth
infections that damage the brain
toxic substances that affect the brain
injury and lack of oxygen to the brain
disturbance in blood circulation to the brain (stroke and other vascular problems)
metabolism or nutritional imbalance
tumors of the brain
genetic or hereditary abnormalities
high fever
other degenerative diseases
malformation of the brain
Seizures can be triggered by a variety of things, such as lack of sleep, alcohol consumption or hormonal changes associated with the menstrual cycle. Although these triggers don't cause epilepsy, they can provoke seizures. Sleep deprivation is perhaps the most powerful trigger of all.
Epilepsy and Reproductive Health Issues.
Epilepsy is associated with many reproductive health issues for women. Reproductive hormones (estrogen and progesterone) can have a strong impact on the frequency and severity of seizures. Many women experience changes in their seizure patterns at times of hormonal fluctuations such as puberty, ovulation, at the beginning of menstruation, pregnancy and even at menopause. This hormone-seizure interaction makes each life stage-and sometimes each menstrual period-a unique challenge for the woman with epilepsy. Because seizures disrupt regions of the brain that regulate reproductive hormones, women who have seizures also are more likely to have reproductive problems such as polycystic ovarian disease, early menopause and irregular ovulation.Even birth control choices are affected by epilepsy. Certain antiepileptic medications (medications that control seizures) make hormonal birth control less effective in preventing pregnancy. Hormonal birth control includes oral contraceptives (birth control pills), long acting progestin shots and implants and intrauterine devices that release hormones. While most women with epilepsy can have healthy babies, they are advised to work with health care professionals knowledgeable about seizure disorders to guard against increased risks for complications during pregnancy. See the Treatment section of this topic for more information on epilepsy and pregnancy
Infertility
Endometrial tissue also may grow in the abdominal area or, more rarely, travel far from the pelvic region into the lungs, skin and other regions of the body. No matter where it goes, however, endometrial tissue continues to respond to hormonal signals--specifically estrogen--from the ovaries each month telling it to grow. Estrogen is the hormone that causes your uterine lining to thicken each month. When estrogen level drops, the lining is expelled from your vagina (you get your period). But unlike the tissue lining the uterus, which leaves your body during menstruation, endometriosis tissue is trapped in the pelvic cavity. With no place to go, the tissue bleeds. Your body tries to stop the bleeding through inflammation, a process that can lead to the formation of scar tissue, also called adhesions. This inflammation and the resulting scar tissue may cause pain and other symptoms.
Recent research also finds that this misplaced endometrial tissue may develop its own nerve supply to communicate with the brain, one reason for the condition's severe pain and the other chronic pain conditions so many women with endometriosis also suffer from.
The type and intensity of symptoms range from completely disabling to mild. Sometimes, there aren't any symptoms.
If your endometriosis results in scarring of the reproductive organs, it may affect your ability to get pregnant. In fact, 35 to50 percent of women with the condition have endometriosis have difficulty getting pregnant. Even mild endometriosis can result in infertility.
Researchers don't know what causes endometriosis, but many theories exist. One suggests that retrograde menstruation--or "reverse menstruation"--may be the main cause. In this condition, menstrual blood doesn't flow out of the cervix (the opening of the uterus to the vagina), but, instead, is pushed backward out of the uterus through the fallopian tubes into the pelvic cavity.
But because most women experience some amount of retrograde menstruation without developing endometriosis, researchers believe something else may contribute to its development.
For example, endometriosis could be an immune system problem or hormonal imbalance that enables the endometrial tissue to take root and grow after it is pushed out of the uterus.
Other researchers believe that in some women, certain abdominal cells mistakenly turn into endometrial cells. These same cells are the ones responsible for the growth of a woman's reproductive organs in the embryonic stage. It's believed that something in the woman's genetic makeup or something she's exposed to in the environment in later life changes those cells so they turn into endometrial tissue outside the uterus. There's also some thinking that damage to cells that line the pelvis from a previous infection can lead to endometriosis.
Some studies also show that environmental factors may play a role in the development of endometriosis. Toxins in the environment seem to affect reproductive hormones and immune system responses, but this theory has not been proven and is controversial in the medical community.
Other researchers believe the endometrium itself is abnormal, which allows the tissue to break away and attach elsewhere in the body.
Endometriosis may also be a genetic condition, with studies finding a 5 to 7 percent increase in risk if your mother or sister had the disorder. Research also indicates that daughters of women who took the drug diethylstilbestrol (DES) between 1938 and 1971 to prevent miscarriage have an increased risk of endometriosis.
Recent research also finds that this misplaced endometrial tissue may develop its own nerve supply to communicate with the brain, one reason for the condition's severe pain and the other chronic pain conditions so many women with endometriosis also suffer from.
The type and intensity of symptoms range from completely disabling to mild. Sometimes, there aren't any symptoms.
If your endometriosis results in scarring of the reproductive organs, it may affect your ability to get pregnant. In fact, 35 to50 percent of women with the condition have endometriosis have difficulty getting pregnant. Even mild endometriosis can result in infertility.
Researchers don't know what causes endometriosis, but many theories exist. One suggests that retrograde menstruation--or "reverse menstruation"--may be the main cause. In this condition, menstrual blood doesn't flow out of the cervix (the opening of the uterus to the vagina), but, instead, is pushed backward out of the uterus through the fallopian tubes into the pelvic cavity.
But because most women experience some amount of retrograde menstruation without developing endometriosis, researchers believe something else may contribute to its development.
For example, endometriosis could be an immune system problem or hormonal imbalance that enables the endometrial tissue to take root and grow after it is pushed out of the uterus.
Other researchers believe that in some women, certain abdominal cells mistakenly turn into endometrial cells. These same cells are the ones responsible for the growth of a woman's reproductive organs in the embryonic stage. It's believed that something in the woman's genetic makeup or something she's exposed to in the environment in later life changes those cells so they turn into endometrial tissue outside the uterus. There's also some thinking that damage to cells that line the pelvis from a previous infection can lead to endometriosis.
Some studies also show that environmental factors may play a role in the development of endometriosis. Toxins in the environment seem to affect reproductive hormones and immune system responses, but this theory has not been proven and is controversial in the medical community.
Other researchers believe the endometrium itself is abnormal, which allows the tissue to break away and attach elsewhere in the body.
Endometriosis may also be a genetic condition, with studies finding a 5 to 7 percent increase in risk if your mother or sister had the disorder. Research also indicates that daughters of women who took the drug diethylstilbestrol (DES) between 1938 and 1971 to prevent miscarriage have an increased risk of endometriosis.
Endometriosis
Endometriosis is a non-cancerous condition in which pieces of the endometrium (uterine lining) grow outside your uterus and adhere to other pelvic structures, most commonly the ovaries, bowel, fallopian tubes, or bladder. It is a common cause of pelvic pain and infertility.
It affects 10 to 15 percent of premenopausal women, according to the American College of Obstetricians and Gynecologists (ACOG), with the National Institutes of Health estimating that at least 5.5 million women in North America alone have endometriosis.
Historically thought of as a disease that affects adult women, endometriosis is increasingly being diagnosed in adolescents, as well.
The most common symptoms are painful menstrual periods and/or pelvic pain.
Others include:
Diarrhea and painful bowel movements, especially during menstruation
Intestinal pain
Painful intercourse
Abdominal tenderness
Severe cramping
Backache
Severe menstrual cramps
Excessive menstrual bleeding
Pain in the pelvic region with exercise
Painful pelvic examinations
It affects 10 to 15 percent of premenopausal women, according to the American College of Obstetricians and Gynecologists (ACOG), with the National Institutes of Health estimating that at least 5.5 million women in North America alone have endometriosis.
Historically thought of as a disease that affects adult women, endometriosis is increasingly being diagnosed in adolescents, as well.
The most common symptoms are painful menstrual periods and/or pelvic pain.
Others include:
Diarrhea and painful bowel movements, especially during menstruation
Intestinal pain
Painful intercourse
Abdominal tenderness
Severe cramping
Backache
Severe menstrual cramps
Excessive menstrual bleeding
Pain in the pelvic region with exercise
Painful pelvic examinations
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