Estrogen can benefit heart health for some menopausal women: study

Researchers have added a new wrinkle to the debate over the safety of hormone replacement therapy with a finding that taking estrogen alone may benefit heart health for a certain group of menopausal women.

In a new study, a followup to the massive U.S. Women's Health Initiative (WHI), the researchers found that menopausal women aged 50 to 59 who took estrogen pills had lower levels of coronary artery calcium compared with women of the same age given a dummy pill.

Coronary artery calcium is an indicator of plaque blockage (hardening of the arteries) that can lead to a future heart attack, said lead author Dr. JoAnn Manson, head of preventive medicine at Brigham and Women's Hospital.

"In a woman who has healthy blood vessels, it (estrogen) seems to slow the early stages of plaque buildup and does not appear to have those risks," Manson said Wednesday from Boston. "It doesn't increase the risk of heart attack."

It is the latest study in recent months to suggest that women who take hormones in early menopause enjoy some health benefits beyond symptom relief. But that's not the case for women who start replacement therapy in their 60s and 70s: the added hormones can actually raise their health risks.

Manson said older women may already have hardening of the arteries, and "estrogen may not only increase the risk of clotting and blocking off the blood vessel, which is already narrowed, but it may actually increase the risk of plaque rupture," leading to a heart attack.

The danger of heart attack - and other health consequences - linked to hormone replacement therapy has been of increasing concern in the last five years, since initial results from the landmark study scared millions of women away from the once ubiquitous menopause treatment.

Before the Women's Health Initiative began in the 1990s, studies had suggested that hormones not only relieved hot flashes and other menopause symptoms, but also appeared to protect women against heart disease, osteoporosis and dementia.

But WHI, the largest-ever study of postmenopausal women, published findings in 2002 that contradicted those assertions and sent up a number of red flags about potentially adverse effects.

One arm of the study, looking at women taking both estrogen and progestin, was abruptly halted in 2002 when evidence showed that taking the hormone combination bumped up the risk of breast cancer, stroke, blood clots and, in the first year of treatment, heart attack.

The estrogen-alone arm of the study involving women who had undergone hysterectomy was stopped in 2004, a year early, because of concerns that estrogen boosted the risk of stroke and blood clots.

While the initial analysis found that estrogen had no effect on heart attack risk overall among WHI participants, who ranged in age from 50 to 79, the new study suggests it could benefit women in their 50s and those within 10 years of menopause.