NIH panel urges caution in use of estrogen for menopause

April 18, 2005

In light of the continuing confusion over what women should do to alleviate their symptoms of menopause, the National Institutes of Health held a state-of-the-science conference on this subject recently. But the conference may have raised more questions than it answered. The NIH-sponsored panel confirmed that there is still much to be learned about this condition. And the same is true of most medications used to treat menopausal symptoms.

In light of the continuing confusion over what women should do to alleviate their symptoms of menopause, the National Institutes of Health held a state-of-the-science conference on this subject recently. But the conference may have raised more questions than it answered. The NIH-sponsored panel confirmed that there is still much to be learned about this condition. And the same is true of most medications used to treat menopausal symptoms.

Issuing its draft statement on the NIH campus outside Washington, D.C., the panel emphasized that menopause should not be "medicalized." Many women have few or no symptoms and should probably not be treated, the panel said.

For most women who have bothersome or debilitating symptoms, low-dose estrogen (equivalent to 0.3 mg conjugated estrogen) has been shown to be effective for hot flashes and night sweats, according to the 12 independent experts from biology, aging, obstetrics, biostatistics, psychiatry, and other fields. Contrary to some news reports on the statement, the panel did not say lower doses of estrogen might be safe but that for women who take estrogen, it seems sensible to take the lower dose. This is important in light of recent findings in the Journal of the American Medical Association, which found that most women who take estrogen are prescribed the traditional standard dose (0.625 mg conjugated equine estrogen or equivalent), the level trials have found to produce greater risk of stroke, deep vein thrombosis, pulmonary embolism, and other events.

As for the various complementary and alternative approaches many women are trying, the panel said there is "a paucity of well-designed studies" on safety or effectiveness. For example, for bioidentical or "natural" hormones, which are individually compounded based on salivary hormone concentration, the panel said that there is a scarcity of data on the benefits and adverse effects.

Dehydroepiandrosterone (DHEA) has not been studied in large trials. Some advocates of DHEA promote it as having therapeutic effects in a number of chronic conditions, among them depression. Although some results of the few short-term studies on antidepressants have been promising, there are side effects to antidepressants. Studies of soy extract suggest some mitigating effect on hot flashes, but results of trials on dietary soy are mixed, information on adverse events is limited, and long-term side effects have not been studied, said the panel.

There are methodological problems with much of the research on black cohosh, the most studied of the botanical products, although trials in progress at NIH may give more answers. At the same time, there have been indications of possible adverse effects on the liver from black cohosh.

For acupuncture, said the panel, there is limited evidence for reduction of hot flashes. The group said that researching behavioral interventions, such as exercise, health education, and paced respiration, might be useful because adverse effects are rare with those types of activities.

According to the panel, medical authorities don't completely understand what menopausal symptoms are and that many problems people attribute to menopause may be due to aging. However, the report said, evidence is strong that menopause often causes vasomotor symptoms, including hot flashes and night sweats, as well as vaginal dryness. The panel recommended new clinical trials on menopause and symptom treatment, particularly research including multiple ethnic groups, since most research to date has been on Caucasian women.