A new Danish study offers some reassurance to women using hormone replacement therapy (HRT) for menopausal symptoms: the treatment may not only ease discomfort from hot flashes, but early use also appears not to increase women’s risk of heart problems or death.
Skepticism surrounding hormone replacement therapy stems from the results of the landmark Women’s Health Initiative (WHI), a large federal study that was halted in 2002 when study authors linked estrogen-progestin pills to increased risks for heart disease and breast cancer.
Since then, follow-up studies have begun to clarify some of the risks and benefits, finding that, for example, women who take estrogen-only hormone therapy (instead of combination estrogen-progestin pills) shortly after menopause don’t have the same elevated heart risks and may even enjoy a lower risk of breast cancer. Only women who have had hysterectomies can take estrogen-only hormone treatments.
In the new study, published in the journal BMJ, researchers divided 1,006 recently menopausal women aged 45 to 58 into one of two groups: an HRT group and a non-HRT group (the women not taking HRT also did not receive a placebo). Originally, the study, whose participants were initially enrolled in 1990-93, was intended to last 20 years. But at 10 years — when results from the WHI came out — the researchers recommended that participants stop taking their hormones. At this point, more women in the non-HRT group had died from heart-related causes.
The researchers continued to track the women for an additional six years and found that women in the HRT group were still less likely to die from heart-related incidents. By the end of the study, 23 women in the non-HRT group had died of cardiovascular-related causes and 17 had died of unrelated causes, compared with six women who had died of heart disease among the HRT group and 21 who died from other causes.
Women taking HRT were also less likely to experience heart attack or heart failure. The authors further report no “apparent increase of cancer…or stroke” among women getting hormone therapy.
However, observers note that the study’s small numbers make it difficult to draw any firm conclusions from its findings. Health experts are not quick to change current recommendations for HRT use: doctors prescribe hormone therapy only to relieve the worst menopause symptoms and only for short periods of time, not to prevent chronic conditions like heart disease, cancer or dementia.
“I wouldn’t recommend HRT to postmenopausal women to reduce heart attacks,” Dr. Mary Ann McLaughlin, director of the cardiac health program at Mount Sinai Medical Center in New York City, told HealthDay. “These results make me feel more confident that some women may benefit from estrogen therapy, but until I figure out which particular women those are, I would not recommend a carte blanche giving estrogen again to prevent heart attacks.”
Still, the authors of the current study note that their study population was a lot younger than the women in the WHI — whose average age was about 63 — and that use of HRT in this younger group may yet prove beneficial. “It doesn’t make sense to treat menopausal symptoms when you are more than 10 years away from menopause. By that time, your entire biology has changed. It’s completely unnatural,” study author Dr. Louise Schierbeck, an endocrinologist at Hvidovre Hospital in Denmark, told WebMD.
Nevertheless, the study has some significant limitations, aside from its small size, which the authors acknowledge. For instance, the study was originally designed to examine the influence of hormone therapy on bone health; the association with heart disease was assessed later. There is also an issue of bias, since both the women and their doctors knew who was taking HRT and who was not. Lastly, there was no placebo group.