Many women believe that coronary heart disease is a man’s disease, but the fact is that heart disease kills more women each year than breast cancer and all other cancers combined. Though heart attacks are less common among women under age 50 than among men, younger women who do have heart attacks are twice as likely to die within a week than men.
As a woman ages, her risk of heart disease increases: 9,000 American women under age 45 have heart attacks each year versus 250,000 women over age 65. Medical experts believe the increased risk of heart disease in older women is related to the depletion of the female hormone estrogen at menopause.
Before a woman reaches menopause, her ovaries produce estrogen, a hormone responsible for regulating the menstrual cycle and secondary sexual characteristics (such as breasts). Estrogen also seems to have a protective effect against heart disease and appears to help maintain low cholesterol levels and improve the arteries’ flexibility and expandability. Pre-menopausal women are still at risk of heart disease, but the risk is significantly lower than for post-menopausal women, according to physicians.
Blood flow through clogged arteries is different for men and women and may explain why a woman’s risk of heart disease increases dramatically as she ages. Physicians believe estrogen helps a woman’s arteries to expand when they become blocked with hardened fatty build-up, allowing the blood to flow around the blockage. In men, the arteries are not as flexible. As a man’s arteries become blocked, they narrow, reducing the blood flow. As men age and their arteries become blocked, the body develops new arteries to serve as back-up blood routes (called collateral blood supplies).
However, women do not develop these collateral blood supplies as they age since, with estrogen, their blood vessels can expand to accommodate blockage. When a woman’s estrogen production ceases at menopause, her arteries tend to lose their flexibility and her risk of heart disease increases significantly since no collateral blood supply is developed. Some women take estrogen replacement therapy (ERT) after menopause to help reduce their risk of heart disease.
Yale epidemiologist Viola Vaccarino, MD says that estrogen deficiencies may be the cause of heart problems in some pre-menopausal women too. In a study of 400,000 patients, younger women were most likely to die within a week of a heart attack than older women or men. Death rates among younger women who have heart attacks are still significantly higher one month after the attack according to a Swedish study. Dr. Vaccarino believes some women do not produce enough estrogen before menopause, leading to an increased risk of heart problems.
According to Laura Wexler, MD, a cardiologist at the University of Cincinnati Medical Center in Ohio, women do not have the same "textbook" heart attack symptoms as men and tend to wait longer to receive medical attention for their heart problems than men. Also, EKG tests, which monitor heart muscle functions, do not show classic heart attack patterns in women as they do in men.
Heart Attack Symptoms |
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| In Both Men and Women | More Often in Women Only |
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The risk factors for a heart attack are similar between both men and women and include: high blood pressure, diabetes, high fat diet, high LDL ("bad") cholesterol levels and triglycerides, and a family history of heart disease. Medical experts believe women who smoke and take birth control pills significantly increase their chances of heart disease because they are at an increased risk of blood clots.
According to several studies, women also seem to wait longer to have their heart problems examined than men. In a study of 1,300 men and 900 women who complained of chest pain, men were more likely to receive medical attention than women. The results of a study of 16 academic medical centers showed that the percentage of women who took drugs for high cholesterol actually declined between 1994 and 1997.
The researchers studied 825 men and women with coronary artery disease. In 1994, only 38% of women and 42% of men with high LDL ("bad") cholesterol levels were taking cholesterol-lowering medication. By 1997, 54% of the men were receiving drugs while the percentage of women who received medication dropped to 35%. Consequently, at the end of the study, 31% of the men had lowered their LDL cholesterol to a safe level (100) while only 12% of the women had done the same. The researchers speculate a sexual bias in the medical industry may be the reason why women are often under-treated for heart disease.
However, new tests are helping to more accurately identify heart disease in women. Instead of EKGs, some physicians are using blood tests to check for increased levels of myoglobin, a protein that binds oxygen to cardiac and skeletal fibers. Myoglobin may subtly indicate cardiac muscle injury. Physicians are also reducing dosages of anti-clotting drugs in women with small bodies to help prevent complications from bleeding.
- The March 13, 2000 U.S. News and World Report article by Josh Fischman, "The ‘Man’s Illness’ Can Be Deadlier to Women Who Don’t Spot Cardiac Trouble," is available at http://www.usnews.com/usnews/issue/000313/nycu/women.htm
- To learn more about heart disease, please visit http://www.imaginis.com/heart-disease/
