Subtle Cognitive Declines Follow Menopause

by Nancy Walsh for MedPage Today:The year after a woman's final menstrual period -- a phase classified as early postmenopause -- is a time in which subtle changes in cognition occur, researchers found.Compared with women in an earlier stage of menopause known as the late menopausal transition phase, those in early postmenopause scored worse on tests of verbal learning (B = −0.93, P<0.01) and verbal memory (B = −0.80, P=0.01), according to Miriam T. Weber, PhD, of the University of Rochester in New York, and colleagues.In addition, women in early postmenopause fared worse on measures of fine motor skills (B = −0.70, P=0.03) and attention/working memory (B = −0.55, P=0.04), the researchers reported online in Menopause.It has been suggested that cognitive and memory changes many women experience in association with menopause may result from associated symptoms such as sleep disturbances and depression, as well as from fluctuating estrogen levels."Estrogen influences hippocampal function, prefrontal cortex function, and the cognitive functions subserved by these brain regions, including verbal memory and executive function," the researchers observed.Previous longitudinal and cross-sectional studies have yielded conflicting findings about the cognitive changes associated with menopause, possibly because of differing staging criteria.However, revised criteria were recently established by an expert group that more clearly delineates the multiple stages of menopause.The new criteria include the late reproductive phase, during which minor changes can be seen in the length of the cycle and pattern of blood flow; the early menopausal transition, characterized by multiple week-long differences in cycle length; the late menopausal transition, with 2-month periods of amenorrhea; and early postmenopause (the first 12 months after the final menstrual period).To more clearly determine the cognitive effects of menopause across the stages of menopause, Weber and colleagues enrolled 117 women whose mean age was 48.7 years.A total of 34 were in the late reproductive phase, 28 were in early transition, 41 had reached late transition, and 14 were in early postmenopause.More than 90% were white, with small numbers of African Americans, Asians, and Hispanics. They were well-educated, with most having about 16 years of education.A battery of cognitive tests measured attention, working memory, verbal fluency, motor skills and dexterity, visuospatial skills, and overall memory. On self-reported questionnaires, participants rated their symptoms of depression and anxiety, as well as overall health.When women in early postmenopause were compared with those in the late reproductive phase, poorer scores again were seen for early postmenopause:

• Verbal learning, B = −0.95 (P=0.02)
• Verbal memory, B = −0.97 (P=0.02)
• Fine motor skills, B = −0.88 (P=0.03)

A trend also was seen for women in early postmenopause to have lower scores for attention/working memory.No differences were seen on cognitive scores for women in the early menopausal transition phase compared with those in late reproductive or late menopausal transition phases.There were no associations between cognitive scores and menopausal symptoms such as hot flashes, sleep disruptions, or anxiety.The researchers further compared cognitive scores according to levels of estradiol, and found an association of higher levels only for fine motor skills (B =0.002, P=0.02).Higher levels of follicle stimulating hormone also were associated only with improved scores for fine motor skills, but this was not significant."The primary finding from our study was that women in early postmenopause performed worse than those in the late reproductive and late menopausal transition stages on verbal learning, verbal memory, and motor tasks, and worse than those in late menopausal transition on measures of attention/working memory," the researchers stated.They also pointed out that the effects were independent of other factors such as mood, symptoms, or hormone levels, which countered their expectations."Taken together, these findings suggest that women's concerns about their memory function during the menopausal transition are warranted, and that they might experience particular vulnerabilities in the year after the [final menstrual period]," they concluded.A larger study is being conducted to more fully elucidate the patterns of change and potential mechanisms. Limitations of the study included the small sample size and participants' high educational attainment, which may limit the generalizability of the findings.Source: http://bit.ly/Sb80h7