Again with women as Experiments

HRT may be linked to dementia

Oestrogen hormone therapy, a treatment for some symptoms of menopause, shrinks women's brains, new research shows.

Elderly women who took oestrogen pills as part of the Women's Health Initiative clinical trial experienced a slight drop in the size of two brain areas important in memory, compared to women on a placebo.

The decrease could explain a previously documented connection between hormone replacement therapy (HRT) and dementia, as well as other less severe forms of cognitive decline, says Susan Resnick, a clinical researcher at the National Institute of Aging in Baltimore, Maryland, who led the study.

The likeliest explanation had been tiny strokes that cut off blood supply to the brain, but another new study found that women on HRT had no more microscopic brain lesions than patients on a placebo.
Study stopped

"We thought we had a very plausible proposal," says Laura Coker, an epidemiologist at Wake Forest University Baptist Medical Center in Winston-Salem, North Carolina, who led that study.

The two reports, which examined volunteers from the Women's Health Initiative with follow-up brain scans, did not address the cause of the brain shrinkage.

Doctors halted the Women's Health Initiative study in two phases in 2002 and 2004, after preliminary results suggested that oestrogen hormone therapy increased the risk of heart attacks, breast cancer, and strokes in older women.

A follow-up study indicated that HRT also put women over 65 at increased risk of dementia.