Can Hormones Protect Women From Dementia?
April 18, 2001 -- In a disappointing turn of events, a drug that is similar to the female hormone estrogen does not seem to protect women from declines in their mental functioning and memory as they age.
Because the drug acts like estrogen in many ways and because estrogen itself seems to provide a mental boost to some -- but not all women -- who take it, scientists had hoped that it would have the same benefits on the brain for women who were already taking the drug to prevent osteoporosis.
But a new study of over 7,700 women published in Thursday's issue of The New England Journal of Medicine shows that the estrogen-like drug known as Evista hasn't lived up to its promise.
After taking it in one of two different dosages for three years to prevent the brittle-bone disease osteoporosis, postmenopausal women on Evista performed no better on tests of their mental abilities than a similar group of women taking a placebo.
If you would like to discuss these findings, or other issues surrounding menopause, go to WebMD's Women's Health: Menopause board.
Study author Kristine Yaffe, MD, says the results, while disappointing, don't close the door on the possibility that estrogen and other estrogen-like drugs such as Evista might offer protection against mental decline for some, but not all, women.
"I think women at risk for [mental] decline, either because they are older or have already some mild problems [with their memory], may benefit the most but we need more data on this," Yaffe, assistant professor of psychiatry at the University of California, San Francisco, tells WebMD.
She says certain factors that are still unknown may play a role in determining if hormones such as estrogen help individual women stave off memory loss and dementia. Those factors may include the age at which the hormone therapy is started, the length of time a woman takes the therapy, and the individual genetic make-up of the woman.
In an earlier study, Yaffe found that women with a specific genetic profile were more likely than those without that profile to get some mental benefits from taking estrogen after menopause. Other experts have suggested that specific subgroups of women may emerge over time whose brains are most likely to benefit from estrogen.
Although the results of the Evista study are discouraging, Richard Mayeaux, MD, says it's premature to conclude that hormone therapy has no role in preserving mental functioning and memory.
"This was an opportunity to try this drug in a large population and it didn't work," says Mayeaux, professor of psychiatry at Columbia University College of Physicians and Surgeons in New York. "There were some modest benefits but not enough for [the scientists] to be convinced that this drug was effective."
But he points out that women in the study may have had even less estrogen than the average woman because they had osteoporosis, which is associated with reductions in estrogen levels.