March 8, 2000 (New York) -- The female hormone estrogen may affect women's moods and preserve their mental abilities as they age. In a review article in the February issue of Psychiatric Annals, researchers say that though the data are not conclusive, recent studies have shown that estrogen also may improve depressed women's response to some antidepressant medications and decrease the risk of dementia and Alzheimer's disease.
Estrogen has been shown to prevent both heart disease and the bone-thinning disease osteoporosis in women after menopause. Some studies also have found that estrogen alone, given as estrogen replacement therapy (ERT), and estrogen combined with the male hormone testosterone, improve mood and symptoms of depression, such as tearfulness and emotional numbness. But other studies have shown no clear difference between estrogen and a placebo (sugar pill) in depressed postmenopausal women.
"I think there is a group of postmenopausal women who do have antidepressant responses to estrogen, and there may be other reasons why estrogen is good for them as well, but we haven't figured out how to identify them," Mary F. Morrison, MD, author of the review article, tells WebMD. Morrison, who is an assistant professor of psychiatry and medicine at the University of Pennsylvania School of Medicine in Philadelphia, says it is not yet clear exactly how estrogen works to alter mood.
Progestin, another hormone that is often given in combination with estrogen as hormone replacement therapy after menopause, has not been as extensively studied for its effect on mood, but at least one study did find much smaller reductions in depressed mood in women taking progestin alone or in combination with estrogen, compared with those taking estrogen alone.
Some studies also have suggested that estrogen may improve response to a group of commonly used antidepressants called selective serotonin reuptake inhibitors (SSRIs). A study by Gary Small, MD, professor of psychiatry and biobehavioral sciences at the UCLA, found that elderly depressed women on ERT had a nearly three times better chance of responding to Prozac, which is an SSRI, compared with those taking a placebo. Small tells WebMD that he and co-author Lon Schneider, MD, also of UCLA, have submitted another article for publication showing similar results using Zoloft, another SSRI.
"It's not clear what is causing this," Small says. "Estrogen has a lot of effects on the brain, and it certainly modulates [serotonin] function, so it could have something to do with that. But there could be some other factors related to these women that has nothing to do with estrogen."
Research also has suggested that ERT may prevent, or at least decrease the risk of, Alzheimer's disease. The National Institute on Aging is currently enrolling postmenopausal women in a three-year study to determine if estrogen therapy can prevent Alzheimer's in women with a family history of the disease. Physicians and patients can get more information on this trial, known as PREPARE, by visiting the institute's web site (www.delay-ad.org) or calling (877) DELAY-AD.
Estrogen is also being studied in women with established Alzheimer's dementia. Two trials showed mental improvements among women with dementia who were taking ERT. But a recent study in the Feb. 23 issue of the Journal of the American Medical Association found no significant changes between the group of elderly women with mild to moderate Alzheimer's disease that took the drug and those who did not.
- The female hormone estrogen, long known to help women prevent heart disease and maintain strong bones, may also help to boost women's mood and response to antidepressant drugs.
- Researchers don't know why some postmenopausal women find psychological benefits when on estrogen therapy, and doctors still don't know how to identify which postmenopausal women would get these benefits from the hormone.
- Scientists also are studying the possible benefits of using estrogen to fight Alzheimer's disease, both before it develops and after diagnosis. Preliminary results released last month showed estrogen therapy offered no significant help to patients who already had mild to moderate Alzheimer's disease.