Short-Term Hormone Replacement Tied to Increased Risk for Recurrent Heart Attack
July 2, 2001 -- The other shoe just dropped on hormone replacement therapy. New evidence from two studies suggests hormone replacement therapy in the short term probably doesn't prevent further heart problems in postmenopausal women with recent heart attacks and that for some women, taking estrogen increases the risk for recurrent heart attack.
With the new evidence, many heart experts say that there is no science to support a claim that estrogen replacement can prevent heart disease.
So strong is the sentiment that JoAnn Manson, MD, chief of preventive medicine at Harvard's Brigham and Women's Hospital, tells WebMD that doctors counseling women about hormone replacement should "take coronary heart disease prevention out of the equation. It is not a factor," says Manson who co-authored one of the new studies.
She says, however, that hormone replacement remains the most effective treatment for eliminating hot flashes, sleep disturbances and other symptoms of menopause.
Heart disease usually strikes women after menopause, when they are no longer producing estrogen, explains L. Kristin Newby, MD, co-author of the second study. Thus researchers reasoned that estrogen protects the heart and giving postmenopausal women estrogen replacement could extend this natural protection.
However, when the estrogen-protects-the-heart theory was tested in a large study, known as the HERS study, researchers found that giving hormones to postmenopausal women who already had heart disease not only didn't help but actually increased their risk of heart attacks during the first year of treatment.
The HERS findings were difficult for many doctors to accept says Newby, who is an assistant professor of medicine at Duke University School of Medicine in Durham, N.C.
In a new study in the July Journal of the American College of Cardiology, Newby and colleaguesstudied over 1,800 women, 111 of whom started hormone replacement after a recent heart attack to assess if therapy would protect the heart against further heart problems.
They found that these 111 women had significantly higher risk of death, heart attack, or chest pain called unstable angina during the first year and half of treatment. The incidence rate for heart problems was 41% for new hormone users compared to 28% of women in the study who had never used hormone replacement.
In a second study Manson and colleagues analyzed the effects of hormone replacement among nearly 2,500 nurses who had previous heart attacks or diagnosed heart disease. She says that in this study, too, in the short-term giving hormones to women who had recent heart attacks increased the risk for subsequent events. Still, long-term users of hormone replacement therapy did show some decreased risk of heart problems. Their findings are reported in July 3 Annals of Internal Medicine.
Manson says both study findings suggest that it is time for women and their doctors to rethink hormone replacement therapy. She says that short-term hormone therapy for women without heart disease "for five years or less to reduce menopause symptoms" is still a good option. But "long-term therapy, for 10 or 15 years, should be carefully weighed."