Postmenopausal women who want to use hormone therapy but are worried about its link to heart disease may find comfort in a new study published this week in the New England Journal of Medicine.
The study found that younger postmenopausal women who take estrogen-alone hormone therapy have significantly less buildup of calcium plaque in their arteries compared to their peers who did not take hormone therapy.
Arterial calcium is considered an indicator of plaque blockage, which can lead to a heart attack.
"These new results offer some reassurance to younger women who have had a hysterectomy and who would like to use hormone therapy on a short-term basis to ease menopausal symptoms," says Dr. Elizabeth G. Nabel, director of the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.
"We must emphasize, however, that these findings do not alter the current recommendations that when hormone therapy is used for menopausal symptoms, it should only be taken at the smallest dose and for the shortest time possible, and hormone therapy should never be used to prevent heart disease."
The findings are from an ancillary study of 1,064 women who were 50-59 years of age at the start of the Women's Health Initiative (WHI) Estrogen-Alone Trial. Participants were randomly assigned to either 0.625 milligrams per day of Premarin or placebo.
Participants took the medications for an average of nearly seven and one-half years. A year after treatment ended, researchers measured the level of calcium plaque in the women's coronary arteries. Those who had taken estrogen were 30 to 40 per cent less likely to have measurable levels of coronary artery calcium compared to those on placebo.
"Although our findings lend support to the theory that estrogen may slow early stages of plaque build-up in the coronary arteries, estrogen has complex effects and other known risks," noted Dr. JoAnn Manson, chief of Preventive Medicine at Harvard's Brigham and Women's Hospital and lead author of the paper.
She says the results are similar to earlier findings that found that younger women treated with estrogen tended to have fewer heart attacks, "but, for an individual woman, it remains uncertain whether the benefits of estrogen would outweigh the risks."
"For this reason, estrogen... may be appropriate for the short-term treatment of moderate-to-severe hot flashes or night sweats among recently menopausal women."
But for women who start HRT in their 60s and 70s, the added hormones may actually increase their health risks.
The WHI study grabbed headlines a few years ago when it concluded that various combinations of hormone replacement therapy did not protect post-menopausal women from cardiovascular disease -- and, in some cases, had the opposite effect.
The estrogen-alone study was halted in February 2004 after seven years because of findings of increased risk of stroke and no reduction in risk of coronary heart disease. The study also found an increased risk of blood clots.
Combination estrogen-plus-progestin hormone therapy was also found to increase the risk of stroke and blood clots regardless of the women's age or time since menopause. Combination therapy was also found to increase the risk of heart disease in the first few years.
