This week a government-sponsored study allayed many women’s fears about the health risks of hormone therapy after menopause, finding that estrogen-only therapy may be less dangerous than previously thought. So, taken together, what does the evidence on hormone therapy mean for thousands of menopausal women?
On one hand, taking drugs to replace the hormones estrogen and progestin, which decline following menopause, can relieve the disruptive symptoms of hot flashes and night sweats that are a hallmark of the “change.” But recent studies have shown that the added hormones can also increase breast cancer risk and, contrary to what researchers had initially thought, do nothing to protect the heart. Those findings are why a multicenter study, the Women’s Health Initiative (WHI), which was designed to gauge the health effects of hormone therapy, was stopped early in 2002.
But one arm of the study, in which women with hysterectomies were given estrogen-only treatment, continued. And reporting Wednesday in the Journal of the American Medical Association, investigators said that women who use estrogen for the short period around menopause don’t need to worry about long-term health problems such as blood clots and strokes associated with the therapy. Whatever increased risk estrogen contributes, they found, dissipates over time. (Only women who have had hysterectomies are prescribed estrogen. Because estrogen can increase the risk of endometrial cancer, women with an intact uterus take the combination of estrogen and progestin to lower that risk.)
So is that the final word on hormone therapy? Probably not, as the researchers continue to analyze the data from both the combination estrogen-progestin trial and the estrogen-only study.
To clarify the various findings, here’s a rundown of what researchers have learned so far:
Estrogen and progestin hormone therapy
Initial results: The WHI found a 24% increased risk of heart disease and a 24% increase risk of breast cancer among women taking the hormone replacement pills compared with women on placebo. The data also showed a 24% decrease in overall fractures among women taking the hormones, but this benefit did not outweigh the risks to the heart and breast.
Follow-up: Three years after stopping the therapy, the risk of heart disease, stroke and blood clots among women taking the pills dropped back to the same levels as those not taking hormones. The small benefit that hormone therapy also had on preventing bone fractures disappeared as well.
Advice: Women who experience severe symptoms of menopause can take the combination of estrogen and progestin therapy for a short period of time during and following menopause, but should not continue to take the pills in order to protect against heart disease. To lower the risk of fractures, there are other medications that aren’t hormone-based that can protect bone.
Initial results: Like the combination of estrogen and progestin, estrogen alone at menopause did not protect against heart disease, but increased the risk of stroke among women taking the pills. Estrogen also boosted the risk of deep vein thrombosis, a source of potentially deadly blood clots.
Follow-up: The harmful effects on the heart resolved after estrogen therapy was stopped, suggesting that the health effects of hormones may be reversible, as long as the hormones aren’t taken for too long. The women in the study were followed for up to seven years.
Advice: Only women who have had a hysterectomy should consider taking estrogen alone. Women with an intact uterus need the progestin to protect endometrial tissue.
For more on the hormone studies, see here.