The Truth About Women and Heart Disease

By Marianne J. Legato, M.D., and Carol Colman

• Understanding Coronary Artery Disease (CAD)
• Profile of the High-Risk Woman

Understanding Coronary Artery Disease

Coronary artery disease has been the number one killer of both men and women since 1910. However, there are important differences in the anatomy, function and lifestyle of men and women that profoundly affect susceptibility to heart disease, and the course the disease takes.

The first and most obvious difference is body size: Women tend to be smaller than men. As a result, most everything else in our bodies is scaled down accordingly. Not only is the typical female heart smaller than the male heart but the coronary arteries-—the vessels that supply blood and oxygen to the heart—are also smaller and narrower. Due to their smaller size, it may take less plaque to block a coronary artery in a woman and impair the flow of blood and oxygen to her heart. There are studies to suggest that women’s coronary arteries may also contract or narrow more vigorously than men’s in response to the same stress.

If all things were equal, women would get heart attacks earlier than men, but just the opposite is true. Although CAD is the leading cause of death in men age 39 and older, it does not become the leading cause of death in women until age 60. In fact, between ages 40 and 49, men are seven times more likely to develop CAD than women of the same age. What protects younger women, but not younger men, against the ravages of CAD? Sex hormones that regulate the menstrual cycle-—specifically estrogen—-are believed to offer women special protection against heart disease. However, once a woman becomes menopausal and her production of estrogen begins to taper off, her risk for developing CAD steadily climbs each year.

When CAD finally strikes women, it hits hard and fast. If the heart is denied sufficient oxygen for about 30 minutes, the result will be a heart attack-—that is, death of a portion of the heart tissue. In many ways, a heart attack is a far more serious event for a woman than it is for a man. When a woman has a heart attack, she is twice as likely as a man to die within the first 60 days. In fact, 39 percent of all women heart attack victims will die within the first year of the attack versus 31 percent of all men. After that, she is twice as likely to have a second heart attack as a man. At any age, a woman is at greater risk of dying of a heart attack than a man. According to a major Israeli study, women suffered a 23 percent death rate during their initial hospital stay versus only 10 percent for men of the same age. For those who survived the heart attack, the one-year mortality rate was l2 percent as compared to only 9 percent for men of the same age.

Not only is a heart attack more lethal for women than for men but in some medical centers standard treatments for CAD--including coronary artery bypass surgery and balloon angioplasty--are not as effective. Fortunately, these days tertiary-care facilities, such as those found at Columbia University, Johns Hopkins and the Mayo Clinic, have outcomes for women that are equal to or better than those or men.

The later age at which heart attack strikes women may be partially responsible for the overall higher rate of death and other complications. The older the person, the harder it is—-physically and psychically—-to mend after a traumatic event such as a heart attack. Women are also more likely to be widowed or living alone, which means that they may not be receiving proper care or emotional support at home after surgery.

Sex Bias
Neither age, body size nor marital status fully explain why women cardiac patients fare so poorly compared to men. The real reason may stem from the fact that women cardiac patients may be sicker than men to begin with, because they are diagnosed and treated at a later stage in the disease. In many cases, women or their doctors-—or both—-have ignored or neglected important warning signs. A case in point is a recent study done at the Cedars-Sinai Medical Center in Los Angeles. The study monitored 1,815 men and 482 women bypass patients between 1982 and 1987. The researchers suggested that there was a definite bias against referring women for bypass surgery: In order for a woman to be operated on, she had to be significantly sicker than a man. The researchers felt that the advanced state of the disease—-not necessarily age—-was the main reason why twice as many women in their study died from the surgery than men (4.6 percent female patients die versus 2.6 percent male patients). The study also suggested that doctors were not referring women for diagnostic testing in a timely fashion, ignoring symptoms in women that they would have probably acted upon in men.

This study is particularly shocking because if it is indicative of other medical facilities--and it probably is--then many women may be suffering and even dying unnecessarily. I believe these findings may reflect a tendency among many physicians to dismiss women’s complaints as trivial. Often, when a woman complains, she is stereotyped as a "whining, hysterical female"--a "head case." But when a man complains, it is automatically assumed that since men are usually more "stoic" about pain than women, he must really be in trouble. Indeed, cardiologists in a study at the Albert Einstein College of Medicine in New York found that only 3 percent of the men had symptoms related to psychiatric problems, as compared to a whopping 10.9 percent of the women! The study may also reflect ignorance on the part of many physicians who are so convinced that women don't get CAD that they don't even consider the possibility; therefore, they neglect to investigate important symptoms.

What I find even more upsetting is my own personal observation that women are not as assertive as they should be on their own behalf. Most women who get heart attacks have experienced intermittent bouts of chest pain or angina long before the actual attack. In many cases, I believe if these women had received proper treatment and made necessary changes in their lifestyle, they may have been able to avert the heart attack altogether, or at least lessened its severity. However, I suspect that many of these women may have too easily accepted their doctor's assurances that they had nothing to worry about, or may have neglected to report the chest pain to their doctors in the first place.

Studies show that many women may neglect to call their doctors even when they are having a full-blown heart attack. About 35 percent of all heart attacks in women (as opposed to 27 percent in men) go unnoticed because the victim believes the pain is due to some non-cardiac problem such as indigestion. Sometimes, in the case of the so-called "silent heart attack," there may be no pain at all. I believe, however, the fact that more than a third of all women's heart attacks go unreported also reflects denial on the part of many women who prefer to believe that the pain was only a minor malady. When the pain goes away, the heart attack victim is only too happy to assume that everything is all right. At some later date an irregular EKG will reveal the scarring or damage left by a previous heart attack.

In defense of doctors, I want to add that women do experience chest pain more often than men and that it is not always caused by CAD. For instance, about 7 percent of all women have a usually benign congenital defect called mitral valve prolapse that can cause pain that can sometimes be confused with angina. In addition, women are more prone to develop spasm of the coronary arteries, which means that for some unknown reason a perfectly clear artery can suddenly constrict or narrow, reducing the flow of blood to the heart. However, there is no way of determining the cause of chest pain unless a woman is thoroughly examined by her physician.

Any chest pain should be investigated for the possibility of CAD whether the patient is male or female. At a very minimum, the physician should perform an electrocardiogram (EKG) to look for signs of damage to the heart muscle or arrhythmia. She should also perform an echocardiogram, a noninvasive test that uses sound waves to examine the structure and function of the heart muscle. In some cases, an exercise stress test may be useful to look for evidence of ischemia or oxygen deprivation, or the patient may be asked to wear a Holter monitor (a small computer that records part of the electrocardiogram for 24 hours) to detect periods of ischemia (time in which the blood supply to the heart is insufficient to maintain it). Unless your doctor has made a serious effort to discover the cause of chest pain, do not accept assurances that you are okay.

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Profile of the High-Risk Woman

A risk factor is any activity or trait that increases your chances of developing a specific disease—in this case, coronary artery disease, or CAD. Chances are that many of you reading this will have one or more risk factors for developing CAD. Perhaps one of your parents died at an early age from a heart attack. Family history of heart disease—your heredity—is a leading risk factor for CAD. Or perhaps your lifestyle puts you at greater jeopardy for heart disease.

Before you panic, let me remind you of an important fact. Just because you may fall into the high-risk category doesn’t automatically mean that your fate is sealed: that somewhere, sometime, you are going to have a heart attack. For one thing, despite the spectacular technological advances in medicine over the past decades, there’s still a lot we don’t know. One of the things we can’t predict with 100 percent accuracy is who will develop heart disease and who will enjoy a lifetime of good health. All we do know is that people who share certain characteristics are more likely to develop heart disease than others. In addition, we know that even women with a number of strikes against them can beat the odds by making positive changes in their lifestyle.

If you have one or more risk factors for CAD, talk to your doctor about ways of minimizing your risk. It may be possible to substantially tip the odds in your favor.

Age
As a rule, the older you are, the greater your risk of CAD. Until age 30, accidents are the leading cause of death in women. From age 30 to 40, cancer becomes the number one killer of women, with accidental death running second. From age 40 to 60, cancer still leads, but heart disease is now in second place. By age 60, men and women are at equal risk for heart disease, and by age 65, heart disease becomes the leading cause of death in women.

Menopausal State
Regardless of a woman’s age, once menstruation ceases, her risk of developing CAD increases between twofold and threefold. Women who have had premenopausal hysterectomies also have a threefold risk increase of CAD.

Body Build
Women who are officially defined as obese—that is, who are between 20 percent and 30 percent over their ideal body weight—are at greater risk of developing CAD. According to a recent eight-year study done at Harvard Medical School and the Brigham and Women’s Hospital, as much as 70 percent of the CAD among obese women, and 40 percent of CAD among women overall, is related to excess weight.

However, several other studies have noted that overall obesity is not as important a risk factor as is the distribution of the excess fat on the body. People who are round in the middle—the so-called spare tire—or shaped like apples, which is more common in men, are at greater risk than people who are shaped like pears, where the weight is concentrated on their bottom half; fat concentrated on the hips and thighs is more typical of women. Recent studies also suggest that women with the thickest skin folds due to obesity have the lowest rates of HDL—the good cholesterol—and therefore run a greater risk of heart disease. In addition, overweight women run a greater risk of diabetes and high blood pressure, which increases their risk of heart attack. Women who kept their weight within normal limits have the lowest rate of heart disease.

Another recent study suggests that shortness may be at the very least a minor risk factor for CAD. According to researchers at Boston University School of Public Health, women who are 4’11" or under are at a 50 percent greater risk of heart attack than women who are at least 5’4". However, since shorter women are more likely to carry their weight at midsection than taller ones, height may be less important than overall body shape.

Family History of Coronary Artery Disease
If you have a father who has had a heart attack before the age of 56, or a mother who has had one before the age of 60, you have an increased risk of developing CAD. The younger the age of your parent or grandparent’s first heart attack, the greater your risk.

Elevated Blood Lipids

High Triglycerides
Triglycerides are a type of fat that can be found in the blood serum and measured by a special test. According to the Framingham study, an ongoing investigation of CAD, women with higher than normal levels of triglycerides—a three-time fasting level of more than 190 mg/dl—were at significantly greater risk of developing CAD than others. Interestingly enough, high triglycerides do not appear to be a risk factor for men until levels approach 400 mg/dl.

High Cholesterol
Cholesterol is a waxy, fatlike substance found in the blood serum. Women typically have higher cholesterol levels than men. However, studies are not consistent in pinpointing the exact level of blood cholesterol that is dangerous for women; 235-265 mg/dl or higher adds significantly to the risk. Even a cholesterol of 235 mg/dl may be too high, but barring other risk factors, a cholesterol of up to 240 mg/dl may be acceptable for a woman.

A lot depends on which type of cholesterol predominates: high-density lipoproteins (HDL) or low-density lipoproteins (LDL). HDL is often referred to as the "good" cholesterol because it may help prevent arteriosclerosis. LDL, known as the "bad" cholesterol, may actually promote clogging of the arteries. Many researchers believe that the overall cholesterol level is not nearly as good a predictor of heart disease in women as the level of HDL versus LDL. Ideally, your HDL-to-LDL ratio should be no more than 4:1. For example, if your HDL is 40 and your LDL is 120, the ratio is 3:1 which is excellent. However, if your HDL is 30 and your LDL is 180, the ratio is 6:1, which is considered poor. Women typically have higher levels of HDL than men and better HDL-to-LDL ratios.

The rule of thumb for everyone is that HDL cholesterol should be higher than 35 mg/dl for men and 45 mg/dl for women; LDL cholesterol should be lower than 130 mg/dl. The average woman has an HDL cholesterol level of 40 mg/dl. In women, HDL drops after menopause, and LDL rises, which undoubtedly contributes to the increased rate of CAD. Women with elevated LDL are at greater risk of developing heart disease.

Diabetes
Women with diabetes--the inability to metabolize properly sugar or glucose--are at four to six times the risk of having a heart attack than nondiabetic women. In fact, diabetic women of any age run the same risk as their male counterparts of having a myocardial infarction. Many diabetic women have higher blood pressure and blood cholesterol levels than nondiabetic women. They also have other circulatory problems that can contribute to the onset of CAD.

High Blood Pressure
Women with elevated blood pressure (above 120/80) run a greater risk of developing stroke, kidney disease and heart disease. As a woman ages, her chances of developing high blood pressure become greater than a man’s. If you have a parent or grandparent with high blood pressure, or if you became hypertensive during pregnancy, you are also at risk of developing hypertension later in life.

Protein in the Urine
During your annual physical, your doctor should take a fresh urine specimen in which she checks for, among other things, the presence of protein. Proteinuria indicates that the kidneys are not functioning properly, due to damage caused by one of a number of diseases, including hypertension. Whatever the cause, proteinuria is a red flag that should not be ignored.

Enlarged Heart
When the left ventricle of the heart is overworked due to high blood pressure, obesity or other problems, the heart wall thickens. In part, this is due to the fact that the hardworking muscle cells become enlarged to accommodate the extra workload. Studies show that an enlarged heart greatly increases a woman’s risk of heart attack and should be taken very seriously.

Increased Fibrinogen Levels
Fibrinogen is a substance produced in the body that is necessary for the proper clotting of blood when injury occurs. Fibrinogen levels are typically higher in women than in men, but increased levels of fibrinogen have been associated with higher than normal rates of CAD. Smokers tend to have higher levels of fibrinogen than nonsmokers.

High Hematocrit Level
Hematocrit, the percentage of the total blood volume made up of red blood cells, can be measured by a simple blood test. A higher than normal level has been associated with sudden death syndrome—death without prior evidence of CAD. A high hematocrit could mean that the tissues of the body are being deprived of oxygen, an early sign of arteriosclerosis or narrowing of the arteries.

Five or More Pregnancies
A new study reports that women who have had five or more children have lower levels of HDL, which puts them at greater risk of falling victim to CAD. Although we can’t say for certain that many pregnancies are a serious risk factor, it’s probably a good idea for women with many children to pay particular attention to their blood lipid levels.

Smoking
Twenty-seven percent of all women smoke. Although the overall rate of smoking is on the decline, women are not quitting as rapidly as men. And one recent study showed that more high school senior girls are smoking than senior boys. Smoking wreaks havoc on a woman's body, as illustrated by the fact that more women today die of lung cancer than breast cancer. Smokers also run an increased risk of heart attack and stroke.

In addition, smokers become menopausal 5 to 10 years sooner than nonsmokers, which also increases their risk of developing heart disease. Young women who smoke have lower levels of the beneficial HDL and higher levels of the harmful LDL than nonsmokers, and women who smoke are more likely to develop severe malignant hypertension than those who don't.

Substance Abuse
There are approximately 4,595,000 women who are alcoholics or are alcohol dependent in the United States. Substance abuse experts also note a dramatic surge in the usage of cocaine and crack among women. Both substances are highly toxic to the heart, especially for women. Cocaine use during pregnancy is especially dangerous for the infant. Women who take cocaine during pregnancy are 10 to 15 times more likely to give birth to a baby with a serious heart defect. According to one recent study, as many as 10 percent of all pregnant women may use cocaine.

Birth Control Pills
Older, high-dose birth control pills were implicated in the development of CAD; new second- and third-generation low-dose oral contraceptives have eliminated much of the risk. For example, for women 16 to 44 years old who are using these newer forms of oral contraceptives, the incidence of thrombosis (blood clots) is very small. The researchers suggest only three strokes in 100,000 might be attributable to the pill, but that this figure might be lessened by avoiding prescription of the pill in women who have cardiovascular risk factors, such as high blood pressure. One caution is still advised for all women: If you smoke, don’t take the pill.

Lack of Physical Activity
Women who lead a sedentary life with little or no physical activity are at three times the risk of developing heart disease as those who don’t. Women who engage in even the most moderate type of exercise—those who walk a half hour a day at least three days a week—have a lower resting heart rate, which could protect them against heart attack.

The Role of Stress
Unrelenting stress can have a toxic effect on the body for both men and women, and I believe it is a leading contributor to the development of CAD. However, most of the research done on stress and heart disease has focused on men, specifically on the type A personality—the aggressive, competitive go-getter who takes the fast track all the way to the cardiac care unit. Although there has been considerably less attention focused on women and stress, a handful of recent studies suggest that many women—especially those with multiple roles at work and at home—are under extreme stress, the kind that raises blood pressure and increases their risk of developing CAD.

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The Female Heart: The truth about women and heart disease. Copyright (c) 1993 by Marianne J. Legato, M.D., and Carol Colman. Reprinted by permission of Simon & Schuster, Inc. The contents of this website are for informational purposes only and are not intended to be used for medical advice. You should consult your physician or health care provider on a regular basis. You should consult your physician immediately with any problem about which you are concerned.