To test the hypothesis that hot flashes specifically relate to verbal memory performance by examining the relationship between objective hot flashes and cognitive test performance in women with moderate to severe vasomotor symptoms.
In an observational study, 29 midlife women (mean age, 53 y) with moderate to severe hot flashes provided measures of objective hot flashes with an ambulatory hot flash monitor, subjective hot flashes with a diary and questionnaire, and objective measures of verbal memory and other cognitive functions with standardized neuropsychological tests.
The mean number of objective hot flashes was 19.5 per day (range, 6 to 35), including 15.3 (range, 6 to 35) during waking hours and 4.2 (range, 0 to 9) during sleep. The mean sensitivity (ie, subjective detection of objectively measured hot flashes) was 60%. Regression analyses revealed that total number of objective hot flashes, sleep duration, and verbal knowledge were significant predictors of delayed verbal memory. Verbal fluency correlated positively with objective daytime hot flashes. Hot flashes did not predict performance on any of the other secondary cognitive measures (ie, attention, working memory, visual memory), although poor sleep predicted worse performance on several outcome measures.
Highly symptomatic women underreport the number of objective hot flashes that they experience by 43%. Verbal memory performance relates significantly to the objective number of hot flashes women experience but not to the number of hot flashes that they report. These findings suggest that physiological factors related to hot flashes, rather than psychological factors, predict poorer verbal memory function.
In this study ambulatory monitors were used to objectively measure hot flashes and, in general, women under-reported the number of hot flashes they experienced by about 43%. Memory problems worsened as the number of objective hot flashes increased, but not as the number of subjective hot flashes increased. These findings suggest that physiological factors associated with hot flashes, rather than psychological factors, might explain the relationship between objective hot flashes and memory declines.
From the Departments of 1Psychiatry, 2Psychology, and 3Obstetrics and Gynecology, University of Illinois, Chicago, IL; 4Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL.
Received November 30, 2007; revised and accepted February 12, 2008.
Funding/support: This research was supported by NIH/NCCAM grants K01AT002321-01 and R21AT001868-01 to P. M. Maki and by 5P50AT000155-01 grant to Norman Farnsworth (PI) for the NIH/NCCAM Botanical Dietary Supplements for Women's Health, with S.E. Geller as PI of the clinical trial in the Center.
Financial disclosure: None reported.
Address correspondence to: Pauline M. Maki, PhD, Department of Psychiatry (MC 913), University of Illinois at Chicago, Chicago, IL 60612. E-mail: firstname.lastname@example.org