IRVINE, CALIFORNIA. Alzheimer's disease (AD) now affects more than four million Americans with a disproportionate number (two thirds) of victims being women. Several small trials have found that estrogen replacement therapy (ERT) may be useful in halting the progression of AD in women. Researchers at the University of California have just released a major report that clearly concludes that ERT does not halt or retard AD in women and may actually worsen some aspects of the condition. The 15-month, double-blind, placebo-controlled study involved 120 women with mild to moderate AD and an average age of 75 years. The women were randomized to receive 0.625 mg/day of estrogen (Premarin), 1.25 mg/day of estrogen or a placebo for a 12-month period. In order to eliminate the risk of endometrial hyperplasia only women who had undergone a hysterectomy were included in the trial. Twenty-three of the women did not complete the trial; four episodes of deep vein thrombosis and four episodes of vaginal bleeding occurred in the estrogen groups (the women experiencing vaginal bleeding were found not to have had a hysterectomy after all).
The researchers found that neither high nor low dose estrogen
replacement therapy does anything to halt the progression of
Alzheimer's disease. As a matter of fact, patients on estrogen
for one year scored worse on the Clinical Global Impression of
Change seven-point scale than did patients in the placebo group
(80 per cent vs. 74 per cent). Patients taking estrogen also
declined much faster over the year when evaluated using the
Clinical Dementia Rating Scale. The researchers conclude that
estrogen has no place in the treatment of AD. Large-scale trials
are currently underway to determine if ERT may be useful in
preventing the development of AD in the first place. (NOTE: This
trial was partially funded by Wyeth Ayerst Pharmaceuticals, the
manufacturer of the estrogen replacement therapy drug used).