Women's health initiative: no decline in dementia risk with estrogen use; Tied to insignificant increases in probable dementia, mild cognitive impairment.(News)

Unopposed estrogen therapy was not associated with a reduction in the incidence of probable dementia or mild cognitive impairment in women aged 65-79 years, according to newly released data from the Women's Health Initiative Memory Study.

The study included a subgroup of women from the estrogen alone and combined estrogen plus progestin arms of the Women's Health Initiative (WHI). Unopposed estrogen therapy was associated with insignificant increases in both probable dementia and mild cognitive impairment, compared with placebo.

When the data for estrogen alone and estrogen plus progestin were pooled, the hazard ratio for the composite end point of probable dementia or mild cognitive impairment increased significantly.

"This likely will not change any of the guidelines--this is just more information on the lack of utility of hormone therapy for the prevention of the chronic diseases of aging." Dr. Jan Shifren, director of the menopause program of the Vincent Obstetrics and Gynecology Service at the Massachusetts General Hospital in Boston, commented in an interview.

Current recommendations from the American College of Obstetricians and Gynecologists and the North American Menopause Society advise against the use of hormone therapy (HT) for anything other than the relief of menopausal vasomotor symptoms. The new data from the Women's Health Initiative Memory Study (WHIMS) are consistent with these recommendations.

"Use of hormone therapy to prevent dementia or MCI [mild cognitive impairment] in women 65 years of age or older is not recommended," reported Sally A. Shumaker, Ph.D., of Wake Forest University. Winston-Salem, N.C., and her colleagues (JAMA 291[24]:2947-58, 2004).

"It's very important to remember that these analyses are in older women and are clearly not addressing the effects of hormone therapy in healthy 50-year-olds who are taking hormones for hot flashes," Dr. Shifren stressed.