Estrogen May be Good for the Brain

Estradiol therapy in postmenopausal women at risk for dementia maintained brain function

(RxWiki News) Hormone therapy for postmenopausal women at risk for dementia may help maintain brain function, but only certain kinds of hormones have shown this effect.

Parts of the brain show decreased function with age. Estrogen has been suggested to protect against this decline.

One way to see if estrogens or other hormones would protect against decline in brain function was to see if hormone therapy would prevent the decline in brain function in people already at risk for dementia.

Recently published research showed that in postmenopausal women at risk for dementia, estrogen therapy in the form of estradiol significantly prevented brain function decline.

"Ask your doctor if hormone therapy might be right for you."

The lead author of this research was Natalie Rasgon, MD, PhD, from the Stanford Center for Neuroscience in Women's Health at Stanford University School of Medicine in Stanford, CA.

This study enrolled 64 postmenopausal women, ages 50 to 65, who had been taking hormone therapy for at least a year. All of the women had at least one of the following factors that put them at increased risk for dementia: a first-degree relative with Alzheimer’s disease, genetic factors for Alzheimer’s disease or a personal history of major depression.

These women were divided into two groups. One group continued to take the hormone therapy they had been using and the other group discontinued their use.

The types of hormone therapy taken by the women varied. Some women took estradiol (a form of estrogen), some took estradiol with progestin, others took a mixture of hormones (CEE) derived from the urine of pregnant mares that included estradiol (brand name Premarin) or CEE plus progestin.

The women in this study were given PET scans that provided images of how different parts of the brain were functioning. PET scans were given at the beginning of the study and two years later.

Compared to women who were taken off their hormone therapy, women who remained on hormone therapy showed a significant preservation of function of the prefrontal cortex, a region of the brain that usually shows decline with age.

In these postmenopausal women at risk for dementia, continued use of estradiol was associated with preserved activity in a number of brain regions. Even though CEE contained some estradiol, women who continued to use CEE demonstrated significant declines in function of some areas of the brain.

If progestin was taken with either estradiol or CEE, the positive effects of estradiol on brain function were no longer seen.

One limitation of this study noted by the authors was that since the women were at risk for dementia, these findings may not apply to postmenopausal women who are not at risk for dementia. Another limitation was that the researchers could not evaluate the effect of hormones on thinking and reasoning because of the small number of women in the study.

“The present findings provide evidence that the use of [estradiol] in postmenopause could be protective against some of the effects of ‘normal’ aging,” the authors wrote.

This research was published in the March issue of PLOS ONE.

Grants from the National Institute on Aging and the National Center for Research Resources at the National Institutes for Health provided funding for this study.

The authors did not declare any conflicts of interest.

Review Date: 
March 11, 2014