Estrogen Does Not Increase Heart Disease Risk, Study Says
By Rob Stein
Estrogen does not increase the risk of heart disease for women in their 50s and may even be protective, according to a new analysis that has renewed debate about the risks and benefits of the hormone for women going through menopause.
The highly anticipated analysis of data from more than 3,000 women who participated in a landmark government study found no increase in heart attacks among women ages 50 to 59 taking estrogen and found some hints the hormone may reduce their risk of the most common killer.
Although the findings fall far short of warranting a recommendation that women take estrogen for their hearts, they do provide comfort that it is safe to use the hormone for short-term relief from hot flashes, insomnia and other troubles of menopause, experts said.
“These findings are reassuring for women who want to use these hormones around the age of menopause in the short term for the relief of symptoms,” said Jacques Rossouw of the National Heart, Lung and Blood Institute, which funded the research published today in the Archives of Internal Medicine.
But other experts, including some of the researchers involved in the new analysis, disagreed sharply about its implications.
“We’re not suggesting at this point that women use estrogen for the express purpose of preventing cardiovascular disease,” said JoAnn Manson of Brigham and Women’s Hospital in Boston. “But this does suggest that more research is needed on younger women and recently menopausal women to explore this question. There may be a window of opportunity when women will have some heart protection from estrogen.”
Others, however, said the findings were so weak that it was impossible to interpret their importance.
They also noted that the hormone increases the risk of other health problems, including strokes, blood clots and possibly dementia.
“That’s really a deceptive message,” said Marcia L. Stefanick of Stanford University. “It confuses the public, and at this point it is just not helpful to add confusion. We tested that hypothesis and showed very clearly that one should not take hormones to prevent cardiovascular disease. Some people just don’t want to accept that.”
The new findings are the latest development in a long, often confusing history of hormone use during and after menopause. For years, millions of women used the hormone alone or in combination with progesterone on the advice of doctors who believed it would alleviate hot flashes, memory problems and other symptoms, protect their bones and reduce their risk of heart disease.
The Women’s Health Initiative, a large federally funded study, stunned women and the medical establishment in 2002 when it concluded that estrogen combined with progesterone not only did not reduce the risk of heart disease but appeared to increase the chances of suffering heart attacks, strokes, blood clots and breast cancer. Hormone use plummeted.
Some researchers questioned the findings, however, saying they may not apply to younger women because most of the subjects in the study were in their 60s and 70s, when they may have been too old to benefit from estrogen.
As part of the study’s final analysis, researchers examined data collected from 3,310 women who were between the ages of 50 and 59 when the study began. About half took estrogen, while the other half took a placebo.
After about seven years, the younger women on estrogen were no more likely to suffer a heart attack or die from heart disease than those on the placebo. In fact, they were about 37 percent less likely to have a heart attack, although that finding could have been due to chance. But when the researchers added together women who died of heart disease, had heart attacks and were treated for or had symptoms of cardiovascular disease, they found a 34 percent lower risk in the estrogen-taking group. That difference did pass a statistical threshold making it unlikely to be due to chance. Only 46 women taking hormones suffered one of those events, compared with 70 of the women taking placebo.