The largest study of its kind to date shows that women may not be able to learn as well shortly before menopause, compared with other stages in their lives.
The research was published in the May 26 print issue of Neurology, the medical journal of the American Academy of Neurology.
Over four years, the researchers studied 2,362 women who were between the ages of 42 and 52 and had had at least one menstrual period in the three months before the study started.
The women were given three tests: verbal memory, working memory and a test that measured the speed at which they processed information. Scientists tested the women throughout the four stages of the menopause transition: premenopause (no change in menstrual periods), early perimenopause (menstrual irregularity but no gaps of three months), late perimenopause (having no period for three to 11 months) and postmenopause (no period for 12 months).
The researchers found that processing speed improved with repeated testing during premenopause, early perimenopause and postmenopause, but that scores during late perimenopause did not show the same degree of improvement. Improvements in processing speed during late perimenopause were only 28 percent as large as improvements observed in premenopause.
For verbal memory performance, improvement was not as strong during early and late perimenopause, compared with premenopause. Improvements in verbal memory during early perimenopause were 29 percent as large as improvements observed in premenopause. During late perimenopause, verbal memory improvement was 7 percent as large as in premenopause.
Combined, these findings suggest that during the early and late perimenopause, women do not learn as well as they do during other menopausal transition stages.
"These perimenopausal test results concur with prior self-reported memory difficulties — 60 percent of women state that they have memory problems during the menopause transition," said Dr. Gail Greendale, a professor of medicine in the division of geriatrics at the David Geffen School of Medicine at UCLA and the study's primary investigator. "The good news is that the effect of perimenopause on learning seems to be temporary. Our study found that the amount of learning improved back to premenopausal levels during the postmenopausal stage."
The study also found that taking estrogen or progesterone hormones before menopause helped verbal memory and processing speed. In contrast, taking these hormones after the final menstrual period had a negative effect: Postmenopausal women using hormones showed no improvement in either processing speed or verbal memory, unlike postmenopausal women not taking hormones.
"Our results suggest that the 'critical period' for estrogen or progesterone's benefits on the brain may be prior to menopause, but the findings should be interpreted with caution," Greendale said.
Other researchers on this study were M.-H. Huang, R.G. Wight, T. Seeman and A.S. Karlamangla of UCLA; C. Luetters of the University of California, Irvine; N.E. Avis of Wake Forest University; and J. Johnston of the Alaska Native Tribal Health Consortium.
The National Institutes of Health (NIH), the National Institute on Aging, the National Institute of Nursing Research and the NIH Office of Research on Women's Health supported the study.
The American Academy of Neurology, an association of more than 21,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. Neurologists have undergone specialized training in diagnosing, treating and managing disorders of the brain and nervous system, such as multiple sclerosis, Alzheimer's disease, narcolepsy and stroke.
The UCLA Division of Geriatrics within the department of medicine at the David Geffen School of Medicine at UCLA offers comprehensive outpatient and inpatient services at several convenient locations and works closely with other UCLA programs to improve and maintain the quality of life of seniors. UCLA geriatricians are specialists in managing the overall health of people age 65 and older and treating medical disorders that frequently affect the elderly, including falls and immobility, urinary incontinence, memory loss and dementia, arthritis, high blood pressure, heart disease, osteoporosis, and diabetes. UCLA geriatricians can knowledgably consider and address a broad spectrum of health-related factors — including medical, psychological and social — when treating patients.
