Women, Menopause, and Heart Disease
Now that you know what heart disease is, you might be wondering why you need to be concerned about it now. After all, if you're just entering perimenopause, you're probably in your forties, or if you've just experienced menopause, you might be in your early fifties. You're far from some old-timer who needs to worry about a failing heart — right?
Actually, you're right about the first part of that statement, but wrong about the last. At forty or fifty, you're far from being an old-timer, but heart disease doesn't strike only the elderly. Heart disease is the number one killer of women age fifty and over. One in five women has some type of heart or blood vessel disease, and every year nearly half a million women in the United States die from cardiovascular diseases.
Women in their childbearing years are less prone to heart disease than are men of the same age. However, according to the American Heart Association (AHA), “Menopause itself appears to increase a woman's risks of coronary heart disease and stroke.” Your risk of heart disease increases when you reach menopause — then just keeps on increasing. If your menopause occurs naturally, the risk rises slowly. But if menopause results from surgery, the risks can rise dramatically and quickly.
From 1999 to 2003 the number of women dying from cardiovascular disease decreased by 5.7 percent. But in every year since 1984, more women than men have died of heart disease, partly because women are more difficult to diagnose and partly because women are not as likely to get appropriate treatment following a first heart attack.
What's Menopause Got to Do with It?
If women have less risk of heart disease before menopause than do men of the same age, with the same contributing risk factors, why does their postmenopausal risk surpass that of men? To understand this surge in risk, it's important to understand some of the root causes of heart disease in any individual. Though later sections of this chapter discuss these risk factors in detail, one of the most important contributors to heart disease is high blood cholesterol levels. When you develop high blood cholesterol levels, you have too much artery-clogging fat in your bloodstream. The diminished supply of estrogen that occurs with menopause, weight gain, and the aging of your cardiovascular system all contribute to developing high cholesterol levels.
Does Menopause Hormone Therapy Lower Your Risk?
A number of medical researchers and scientists believe that a woman's own natural estrogen might help protect her from heart disease, but they're still studying how the hormone may have that effect. Estrogen plays an important role in maintaining healthy, strong muscle tissue, including the muscle of the heart. Estrogen also has an impact on the blood's level of triglycerides and low-density lipoproteins (LDL) or “bad” cholesterol, both of which can contribute to atherosclerosis and heart attack. Some studies have shown that estrogen contributes to healthy, reactive arteries and an increased blood flow. As a result, blood vessels are better able to relax and respond to exercise and physical stress by dilating and providing more blood flow when needed.
The American Heart Association (AHA) recommends not placing women on menopause hormone therapy for the sole purpose of preventing or treating cardiovascular disease. While it may be effective for other symptoms, it has not been proven effective in reducing heart disease in postmenopausal women, and may actually increase their risk.
Does that mean that you can avoid heart disease through estrogen or other hormone therapies? Not necessarily. As we learned with the Women's Health Initiative (WHI) study described in Chapter 11, women on some types of hormone therapy may actually have an increased risk of heart disease, stroke, and blood clots. Analysis of another study, The Harvard Nurses Health Study, showed that beginning estrogen therapy very soon after menopause does seem to offer some protection from cardiovascular disease, but starting it ten years or more following menopause does not offer that protection.
Are Women Really Different From Men?
The answer to this is yes, yes, yes! Women are more likely to die of their heart attacks and strokes than men are, even though men have more of these events. Here are some of the differences:
Women minimize their cardiac symptoms. Women seem to “tough it out” more than men, and studies show that when men and women have the same severity of heart disease, women rate it as “mild to moderate” while men rated theirs as “severe.” This keeps women from getting the quick and thorough follow-up care they need.
Women can have different symptoms than men. Women sometimes have only anxiety, or a “doomed” feeling; may be “suddenly very tired”; may vomit; or may have burning abdominal pain. Since these are not the symptoms people think of for a heart attack, they put off getting to the hospital.
Women may have a condition called “coronary microvascular syndrome.” In this condition, plaque forms evenly in their arteries, and blockages do not show on diagnostic tests. But the artery walls are still blocked at the microscopic level, thus leaving them at risk for a heart attack.
Women who have symptoms of a heart attack and whose diagnostic studies show no blockage in their arteries should also be screened with the Duke Activity Status Index. This twelve-item questionnaire asks patients to report whether they can perform a number of daily activities without problems. If they respond that they can't do these activities, then the doctor can order further testing to rule out micro-vascular syndrome.