Faced with ongoing neglect and misunderstanding about cardiovascular disease and women, the American Heart Association has chnaged its approach.
In new guidelines, the association directly addressed a misleading paradox about women and heart disease: Although women tend to be at low short-term risk for CVD compared with men, they have a one-in-three lifetime risk of dying of the disease. In fact, CVD is more prevalent among women than men and so is CVD-related mortality.
"If a woman has a one-in-three chance of dying from a specific medical condition, it makes no sense to think of that condition as low risk," said Lori Mosca, M.D., director of preventive cardiology at New York-Presbyterian Hospital and chairwoman of the AHA guidelines committee. "From a long-term view of heart disease prevention, the importance of healthy lifestyles in women of all ages can't be overstated," she said.
"The problem remains that heart disease is seen as a man's disease," said Nanette K. Wenger, M.D., professor of medicine in the division of cardiology at Emory University School of Medicine and a coauthor of the guidelines. "What we do know is that knowledge of what constitutes a healthy lifestyle is as important to a woman as to a man. Knowledge is empowering."
One theory about why providers and patients view women and heart disease in a different light is that much of the research has focused on men, according to C. Noel Bairey Merz, M.D., medical director of the Preventive and Rehabilitative Cardiac Center at Cedars-Sinai Medical Center. She leads the Women's Ischemia Syndrome Evaluation (WISE), sponsored by the National Heart, Lung, and Blood Institute.
Merz and her colleagues have studied gender differences in CVD. They found that many women with heart disease fail to receive a proper diagnosis because they have a form of the disease that does not show up on the usual diagnostic tests. In the WISE study, women with chronic chest pain underwent standard diagnostic procedures, including stress tests and coronary angiograms. Researchers found that among people who show signs of trouble on stress tests, women are far more likely than men to appear free of blockages on follow-up angiograms.
But the researchers also found that newer tests, including ultrasound of the blood vessels, revealed heart problems the angiograms failed to find. Many of the women in the WISE study had a condition called vascular dysfunction, in which the blood vessels supplying the heart do not expand properly to accommodate increased blood flow. Vascular dysfunction may affect not only the large coronary arteries, but also the smaller vessels that serve the heart, a problem known as microvessel disease.
"These results may help explain why women with heart disease are often underdiagnosed and undertreated," said Merz. "With men, the main problem may be a blockage in a large coronary artery, which does show up on an angiogram. But women are more likely to have microvessel disease that can't be seen."
The WISE study also found that women develop heart disease about 10 to 15 years later than men, largely because of the proven cardioprotective effect of female hormones. Some women, especially younger women, who have a heart attack, do not have high levels of fatty plaque clogging their arteries. As a result, many women go undiagnosed, according to the WISE research.
In part because of these findings, a group of female lawmakers recently introduced federal legislation to improve heart disease education among women, increase the amount of gender-specific heart disease research, and increase women's access to heart disease screening. The measures, introduced in both the House and Senate and titled the "HEART for Women Act," requires health information to be reported to the Food & Drug Administration to specify gender, race, and ethnicity.