ESTROGEN TO TREAT ALZHEIMER’S DISEASE
ESTROGEN TO TREAT ALZHEIMER’S DISEASE
(1998 )
The female hormone estrogen has been making headlines for years as an effective therapy in reducing women’s risk of osteoporosis during and after menopause, as well as for easing symptoms of menopause, such as hot flashes. Estrogen replacement therapy (ERT) also has shown significant benefit in reducing the risk of heart disease and substantially lowering the risk of heart attack. Now there’s evidence that estrogen may have a protective effect against the development of Alzheimer’s disease.
Hopeful news
When scientists reported in 1995 that women past menopause who took estrogen were 40 percent less likely to die of Alzheimer’s disease, it captured the interest of researchers and the more than 36 million women in the United States who have been through menopause. Could estrogen replacement therapy protect against Alzheimer’s disease? More encouraging news followed.
In June, 1997, the report of a long-term study from the National Institute on Aging (NIA) documented that estrogen replacement therapy in post-menopausal women was associated with a 50 percent reduction in the risk of developing Alzheimer’s disease. In all, 472 women were studied for 16 years.
The study, important because it was one of the first long-term analyses of estrogen’s effect on preventing Alzheimer’s, was made possible by health data from the NIA’s Baltimore Longitudinal Study of Aging (BLSA). Now in its 40th year of studying aspects of aging in more than 2,000 people, BLSA is one of the largest ongoing studies of its kind.
NIA scientists emphasized that their positive results were preliminary and that more investigation was needed to confirm estrogen replacement therapy’s positive effects. Only 6 months later, another NIA study, conducted between 1978 and 1994, documented the effects of estrogen in slowing the decline of visual memory in 288 women. The study showed that women who received ERT during the memory testing period performed better than women who had never taken estrogen.
Pinpointing estrogen’s role
While research continues, there is still no clear understanding of how estrogen works to lower the risk of Alzheimer’s disease or delay the onset of symptoms. Some research suggests that it actually helps brain cells survive, thus slowing the onset of the disease. The results of other studies suggest that it has a role in preventing the formation of beta-amyloid fibers (a protein associated with neuron damage) in the brain. Another theory is that estrogen works as an antioxidant to protect nerve cells.
For now, estrogen is not prescribed solely for its protective effects against memory loss and Alzheimer’s. But it may offer that added benefit to women already taking it for other reasons.