Heart Disease Often Undiagnosed in Women, Study Finds
As many as three million women in the U.S. might have a cardiovascular condition called coronary microvascular syndrome that places them at higher risk of a heart attack but often goes undiagnosed because its symptoms do not appear on an angiogram, according to research released on Tuesday by NIH, the Chicago Tribune reports (Peres, Chicago Tribune, 2/1). The leading cause of death in the U.S., heart disease kills about 480,000 women annually, and more women than men die of the disease, according to the American Heart Association (Neergaard, AP/Oregonian, 1/31).
The new findings, which appear in several papers to be published in a supplement to the Feb. 7 issue of the Journal of the American College of Cardiology, are the latest results released from the ongoing Women's Ischemia Syndrome Evaluation (Stein, Washington Post, 2/1). The WISE study began in 1996 and tracks about 1,000 women with the goal of improving diagnosis and expanding understanding of heart disease in women (Rubin, USA Today, 2/1).
The participants -- who live in Florida, Pennsylvania and Alabama -- were enrolled after they experienced chest pain and other symptoms of heart disease but showed no evidence of blockage in an angiogram (Maugh, Los Angeles Times, 2/1). Their average age was about 58, although one quarter of participants were premenopausal (Grady, New York Times, 2/1).
According to the research, coronary microvascular syndrome accounts for about 15% of all coronary artery disease in women, Noel Bairey Merz, a cardiologist at Cedars-Sinai Medical Center and chair of WISE, said (Los Angeles Times, 2/1). In the condition, plaque accumulates fairly evenly inside the major arteries and smaller blood vessels, or the arteries fail to expand correctly or go into spasm, the findings show. Other symptoms include fatigue, upset stomach and pain in the jaw or shoulders. However, because many women with symptoms do not show signs of blocked arteries on standards tests, doctors sometimes "send them home without treatment or refer them to psychiatrists," according to the Post. Further, the findings show that women who do receive treatment for heart disease might not benefit from standard drugs, bypass surgery, angioplasty or other conventional therapies (Washington Post, 2/1).
However, as with arterial blockages, the plaques formed in coronary microvascular syndrome can interfere with blood flow and damage the heart muscle, leading to ischemic heart disease, a condition characterized by inadequate blood flow to the heart. According Carl Pepine, chief of cardiovascular medicine at the University of Florida and a lead investigator in WISE, the results show:
- One-third of participants had obvious blockages in their arteries. By comparison, about three-quarters of men in a group similar to the study participants would have blockages.
- Of participants without obvious blockages, more than half had abnormalities that could cause ischemic heart disease.
- After four years, the rate of deaths or heart attacks among participants without obvious blockages was 10%, "much too high for somebody with a normal coronary angiogram," according to Pepine.
- Tests on study participants indicated that the artery walls were full of plaque but had expanded to accommodate it, resulting in an opening that appeared normal (New York Times, 2/1).
The researchers included a number of recommendations in their reports. The recommendations included:
- Women with symptoms of cardiovascular disease should be administered a test of functional capacity, such as the Duke Activity Status Index, a 12-item questionnaire evaluating difficulties performing everyday activities.
- Doctors should avoid treadmill tests, which fail to identify 40% of women with ischemic heart disease, and opt for more sophisticated stress tests and chemical stress tests.
- Premenopausal women with high blood pressure and overweight women of all ages should be considered at high risk of heart problems (Chicago Tribune, 2/1).
The researchers said it is unclear why women are more likely to have hidden heart disease than men, although they speculated it could be related to hormonal imbalances and a greater likelihood to experience inflammation (New York Times, 2/1). Bairey Merz said, "What we're saying is that in many cases heart disease is a fundamentally different disease in many women in ways that we need to pay attention to" (Washington Post, 2/1). She added, "One of the biggest take-home messages from this study is that we must stop falsely reassuring women when their arteries are open" (Los Angeles Times, 2/1). Bairey Merz noted that coronary microvascular syndrome "appears to be primarily a women's problem which is probably why we've missed it all these years (that) we didn't bother to study women." About 20% of individuals with coronary microvascular syndrome are men, she said.
George Sopko, a project officer for WISE and a heart specialist at the National Heart, Lung and Blood Institute, said, "The [number one] message for women is, 'Pay attention to your symptoms.' If you don't have visible blockages, that doesn't mean you're not at risk" (AP/Oregonian, 2/1). Sopko said the message for doctors is, "If you have (a patient with) symptoms and evidence of ischemia, even if the angiogram doesn't show significant blockage, you don't send her home. You treat her as a patient at higher risk." He also recommended that doctors develop a long-term strategy for treatment -- including encouraging patients to increase activity, quit smoking, lose weight and improve lipids and blood pressure. Sopko said researchers are "not yet ready to change the treatment guidelines, but at least now we can tell [patients] what the problem is, even if we don't yet have the best therapies" (Chicago Tribune, 2/1).
Lori Mosca of Columbia University said, "We need to be careful about research comparing women to men that involved only women." She added, "This could be very important to understanding heart disease in women, but we need to do more research that involves both men and women" (Washington Post, 2/1).
Matthew Sorrentino, a cardiologist at the University of Chicago Hospitals, said some of the diagnostic tests recommended by the WISE researchers are experimental. He added, "There has been a definite decline in fatal heart disease in men, but not in women," noting, "We're not picking it up as well in women, and we're not reducing their rate of cardiac events" (Chicago Tribune, 2/1). Abstracts of the papers are available online.
ABCNews' "World News Tonight" on Tuesday reported on the study. The segment includes comments from Bairey Merz and Sharonne Hayes, director of the Mayo Clinic's Women's Heart Clinic (Pinto, "World News Tonight," ABCNews, 1/31). Video of the segment is available online.This is part of the California Healthline Daily Edition, a summary of health policy coverage from major news organizations. Sign up for an email subscription.