By Merritt McKinney
NEW YORK, Feb 22 (Reuters Health) -- Taking estrogen replacement therapy
does not slow down the progression of mild to moderate Alzheimer's disease in
elderly women, according to a new study.
Even though some research has suggested that taking estrogen may be
beneficial to women with the progressive neurological disease, women in the
study who took hormone replacement therapy fared no better than those taking a
dummy placebo pill, researchers report in the February 23rd issue of The Journal
of the American Medical Association (JAMA).
"We are disappointed with our results," the study's lead author, Dr. Ruth
A. Mulnard, of the University of California at Irvine, told Reuters Health in an
interview. "Our study shows pretty strongly that estrogen has no role in
treating Alzheimer's disease in women with mild to moderate disease."
"That does not mean that women with Alzheimer's disease should not be
given estrogen for other purposes," Mulnard said. She noted that estrogen can
help strengthen bones and improve cardiovascular health. Mulnard also said that
estrogen may turn out to have a positive effect on Alzheimer's when given very
early in the disease, before symptoms begin.
The researchers based the conclusions on a study of 120 women with mild to
moderate Alzheimer's. The researchers included only women who had undergone a
hysterectomy -- surgery to remove the uterus -- since treatment with estrogen
alone, without another hormone called progesterone, can increase the risk for
abnormal growths in the lining of the uterus.
The women were randomly assigned to receive either a high or low dose of
estrogen or a placebo pill each day. Neither the researchers nor the women knew
who was taking estrogen. After a year, all three groups took the placebo for 3
months.
After 2 months, the women in the estrogen groups scored somewhat better
than the placebo group on one assessment of Alzheimer's disease, but this
difference disappeared by the end of the study, according to the report. In
fact, on a standardized test that measures dementia, women taking hormone
replacement therapy appeared to decline more rapidly than women taking the
placebo.
Overall, taking estrogen did not lead to an improvement in mental skills
or in the ability to carry out daily activities, with 80% of women taking
estrogen and 74% of those in the placebo group worsening during the study, the
researchers report.
"The results are clear and unequivocal: estrogen does not halt the decline
in cognitive function in (Alzheimer's disease)," write Dr. Bennett A. Shaywitz
and Dr. Sally E. Shaywitz, both of Yale University School of Medicine in New
Haven, Connecticut, in an editorial that accompanies the study.
However, as Mulnard mentioned in the interview, the editorialists note
that there is still a need for studies to see whether early treatment with
estrogen may delay or even prevent symptoms of Alzheimer's disease.
