Estrogen Therapy May Protect Brain
Hormone Use Before Age 65 Linked to Reduced Risk of Dementia
May 2, 2007 (Boston) -- Taking estrogen replacement therapy before age 65
appears to protect women from developing dementia later on, a new study
Researcher Victor Henderson, MD, says the findings suggest early use of
estrogen may be protective for the brain. Henderson is a professor of
health research and policy and of neurology and neurosciences at Stanford
The study showed that women who used any form of estrogen therapy before age
65 were about 50% less likely to develop any form of dementia, including
"We found that it didn't matter whether she took estrogen alone or in
combination with progestin, whether she started at 50 or 60, or how long she
took it for," Henderson tells WebMD.
The study was presented at the 59th annual meeting of the American Academy
Estrogen's Protective Effect
The new research involved about 2,500 participants in the Women's Health
Initiative Memory Study who started taking hormone therapy before age 65.
The women were enrolled in the study from 1993 to 1998. Over the next five
years, 106 of them developed any form of dementia, 53 of whom had Alzheimer's
Results showed that women reporting previous hormone therapy were 46% less
likely to develop any form of dementia and 64% less likely to develop
Alzheimer's disease than women who did not take any hormone therapy before that
Henderson says that one drawback of the study is that participants were
asked to recall if they had ever used hormone therapy as opposed to having
researchers go through their medical records.
The Hormone Debate
The findings are sure to renew the debate about hormone replacement therapy
(HRT). For decades, women were told that HRT -- usually a combination of
estrogen and progestin, but sometimes estrogen alone -- would not just relieve
hot flashes and other symptoms of menopause, but also could protect them
against heart disease and other ailments.
Then the 2002 results of the Women's Health Initiative study seemed to show
just the opposite: hormone replacement therapy actually raised the risk of
heart attacks, strokes, and cancer. About two-thirds of women taking HRT
Since then, the pendulum has begun to swing back a little.
"People may be softening their views," Ronald Petersen, MD, director
of the Alzheimer's Disease Center at the Mayo Clinic in Rochester, Minn., tells
"We may not have to be as frightened as we were," says Petersen, who
did not participate in the study.
While Petersen says he would not prescribe HRT to younger women based
on the new findings alone, he thinks studies like this will make doctors less
reluctant to prescribe estrogen to women who really need it to relieve
disabling hot flashes or other menopausal symptoms. He says he would try to
limit treatment to a year or two until the symptoms passed.
Henderson stresses he doesn't think the findings should change clinical
practice. He says previous research has shown that starting estrogen therapy
after age 65 increases by 50% the risk of later developing dementia.
Petersen speculates that one possible reason for a harmful effect later on
might be that after a certain point in a woman's life, HRT acts a catalyst for