Staying Smart with Estrogen: Estrogen Replacement and Mental Functioning

Losing your keys? Losing your patience? Losing your mind? If you are a midlife woman having difficulties, the solution may be increasing your estrogen level. More and more research studies are showing beneficial effects of hormone replacement on mental functioning. Women taking estrogen showed increased brain activation and reinstated patterns observed in younger subjects performing memory tasks, according to a recent study.

This study found altered neural circuitry in certain parts of the brains of postmenopausal women (average age 50) as they performed memory tasks. In a well-controlled experiment, 46 women were tested when they were taking estrogen and when they were taking a placebo with no estrogen. The dose of estrogen was what is typically prescribed to postmenopausal women (1.25 mg of conjugated equine estrogens).

I conducted a phone interview with Sally Shaywitz, M.D., of Yale University School of Medicine. She was the lead author of "Effect of Estrogen on Brain Activation Patterns in Postmenopausal Women during Working Memory Tasks" published in the April 7, 1999, edition of the Journal of the American Medical Association [JAMA, 1999, 281(13), 1197-1202].

The authors included collaborators from pediatrics, neurology, diagnostic radiology, gynecology, and applied physics. This experiment used a unique means of studying mental processes-the functional magnetic resonance imaging (MRI). Dr. Shaywitz says, "Almost a decade ago, my husband and collaborator, Dr. Bennett Shaywitz first suggested that our research group use functional MRI to study reading and memory. It is a noninvasive test with future potential for being used clinically." She writes, "In performing a cognitive task, such as working memory, blood flow and oxygen concentration are altered in those brain regions engaged by the task" (p. 1198). In this study, the functional MRI found that while on estrogen compared to placebo women's brain activation patterns during memory tasks resembled those associated with younger (compared to older) people.

We talked about the implications of these findings for midlife women. Dr. Sally Shaywitz states, "I seem to have become the repository for women's stories of memory changes". Some women told her they noticed improved memory after starting estrogen replacement therapy. Others came forth with reports of forgetting simple things and of being too embarrassed or afraid to tell their doctors. "Many women feel that there is a prejudice against menopause," she explains.

Dr. Shaywitz points out, "Every woman who lives to the age of menopause will go through these changes [in mental function]." Patients should not be intimidated about talking openly with their healthcare providers. Not all problems are due to sleep deprivation, depression, or aging alone. Physicians should inquire about cognitive changes in women in their late 30's or early 40's whose estrogen levels are beginning to decline. Dr. Shaywitz says, "Verbal memory, fluency, and articulation are functions used in everyday life that may be sensitive to estrogen".

This study opens the door to future research of mental functioning in midlife people. "Brain circuitry can be changed. Midlife is apparently a time of great brain plasticity. The brain can rewire!" Dr. Shaywitz exclaimed. The evidence is mounting that estrogen therapy CAN improve the daily life of many women. However, this is a complex issue and must be made on a highly individual basis. See your doctor about what you may be able to do to improve yours.