Alzheimer's disease is a common, progressive, degenerative disease of the brain. It is characterized by loss of memory and other cognitive functions.
Earlier research suggested a possible role for estrogen in preventing Alzheimer's disease in women. One study showed that women who took estrogen after menopause were less likely to develop Alzheimer's disease. It also suggested that Alzheimer's disease might occur later in life among women who take estrogen. Women who have never taken estrogen may have Alzheimer's disease at an earlier age.
This research, however, was limited and of less-than-ideal quality. Other research done with animals suggested that estrogen might have the following effects: prevent the death of some brain cellslessen deposits of a material in the brain that affects brain cell function. These deposits may help cause Alzheimer's disease.
Studies assessing the relationship between estrogen therapy and Alzheimer's disease have continued to be published over the last several years. The best evidence now indicates that estrogen therapy does not help prevent Alzheimer's and in fact, in some women, might possibly have the opposite effect.
Any woman considering using estrogen therapy must remember that it, like any long-term medication, has risks, benefits, and possible side effects. For example, estrogen therapy may increase the risk of blood clot, heart attack or stroke. There is also an increased risk of cancer of the uterus if a woman takes estrogen and has not had her uterus surgically removed. This risk can be eliminated if a woman who still has her uterus takes a form of the hormone progesterone along with estrogen.
Estrogen therapy does help with symptoms of menopause, such as hot flashes and vaginal dryness. It can also reduce the risk of the bone-thinning condition called osteoporosis and broken bones that can result from that disease.
All women should discuss estrogen therapy use after menopause with their healthcare professional to decide if the benefits outweigh the risks for them. New data about the risks and benefits are still being generated. At this time, however, the data do not support its use to prevent or treat Alzheimer's disease.
[hyperLink url="http://www.Alzheimers.org/" linkTitle="Alzheimer's"] Alzheimer's[/hyperLink] website (from the National Institutes on Aging, a division of NIH)
Tang et al., The Lancet, 1996; 348:429-432.