lavalamp, I went to the alzheimer.org home page and they don't seem to think that there are big differences in incidence between sexes. However, at Alzheimer.com, they also note a higher rate among women, and cite some references for treatment with estrogen:
Estrogen
Compared with men, women are at greater risk of developing Alzheimer's
disease. But recent studies show that they also have a treatment option
unavailable to most men--the female sex hormone estrogen, which helps prevent,
delay, and treat Alzheimer's disease.
Several studies show that women who take estrogen after menopause have an
unexpectedly low incidence of Alzheimer's disease. Among women with
Alzheimer's, those taking estrogen suffer less severe symptoms and slower mental
deterioration. In addition, animal studies show that estrogen improves blood
circulation through the brain, and stimulates nerve cell growth in areas of the brain
affected by Alzheimer's.
These findings are summarized in a report published in the July 1996 Journal of
the American Geriatric Society by Stanley Birge, M.D., a geriatrician at the
Washington University School of Medicine in St. Louis. Birge calls these estrogen
findings "terribly exciting" and potentially "among the most promising recent
discoveries about treating Alzheimer's."
Estrogen boosts the production of acetylcholine, a key chemical
(neurotransmitter) involved in the transmission of nerve impulses across the tiny
gaps between nerve cells (synapses). Estrogen also impedes the deposition of
beta-amyloid, the protein involved in the characteristic plaques of Alzheimer's
disease. In addition, estrogen improves blood flow through the brain, and
enhances verbal abilities of postmenopausal women who take hormone
replacement therapy. Estrogen also helps maintain the integrity of the
hippocampus, a structure in the brain involved in memory. (Kawas, C. et al.
"Treating Alzheimer's Disease: Today and Tomorrow," Patient Care, Nov. 15,
1996, 62-83.)
Several lines of evidence show that estrogen helps both prevent and treat
Alzheimer's disease:
Several epidemiological studies show that taking estrogen reduces
women's risk of Alzheimer's disease. (Paganini-Hill, A. et al. " Estrogen
Deficiency and Risk of Alzheimer's Disease," American Journal of
Epidemiology (1994) 140:256.) Notably, New York City researchers
investigated Alzheimer's risk among 1,124 elderly women. During the
follow-up period, the disease developed in 14.9 percent of them. Among
women who had never used estrogen, the figure was 16.3 percent, while
only 5.8 percent of estrogen users developed Alzheimer's. Among
estrogen users, risk decreased with hormone use longer than one year.
(Tang, MX et al. "Effect of Estrogen During Menopause on Risk and Age
at Onset of Alzheimer's Disease," Lancet (1996) 348:429.)
In a 30-week study of 318 women with mild to moderate Alzheimer's
disease, all participants took tacrine (Cognex), one of only two drugs
currently approved to treat the disease, and some also took estrogen
replacement therapy. Compared with those on tacrine only, the women
taking tacrine plus estrogen fared better on a number of cognitive
measures. (Schneider, LS et al. "Effects of Estrogen Replacement Therapy
on Response to Tacrine in Patients with Alzheimer's Disease," Neurology
(1996) 46:1580.)
In an eight-week study of 12 Tacoma, Washington, women with mild to
moderate Alzheimer's, all the women received skin patches--half that
released estrogen into the blood, and half that contained a placebo. "The
estrogen had a rapid effect," said Sanjay Asthana, M.D., who presented
the results at a meeting of the Society for Neuroscience. "Within a week,
the women on estrogen showed improvement." By the end of the study,
the estrogen users' cognitive test scores had almost doubled. The more
estrogen the women absorbed, the greater their mental improvement.
(New York Times, Nov. 21, 1996)
Finally, as part of the 38-year Baltimore Longitudinal Study of Aging,
researchers from the National Institute on Aging assessed 16 year's worth
of medical records for 514 postmenopausal women. They found that
compared with women who had never taken estrogen, those who had
were 54 percent less likely to develop Alzheimer's disease. (Stephenson,
J. "More Evidence Links NSAID, Estrogen Use with Reduced
Alzheimer's Risk," Journal of the American Medical Association (May
8, 1996) 275:1389.)
In addition to helping prevent and treat Alzheimer's disease, a great deal of
research shows that the sex hormone also helps prevent heart disease, women's
leading cause of death, and osteoporosis, bone-thinning that can lead to serious
fractures.
But for all its benefits, estrogen also carries some risks. It increases breast cancer
risk an estimated 20 to 30 percent, and also increases uterine cancer risk if the
woman takes it without another sex hormone, progesterone. |
