Objective: To estimate the prevalence of perceived poor sleep in women aged 35-49 years and to correlate sleep quality with levels of gonadal steroids and predictors of poor sleep.
Methods: A cohort of 218 black and 218 white women aged 35-47 years at enrollment (aged 37-49 at final follow-up) with regular menstrual cycles was identified through random digit dialing for a longitudinal study of ovarian aging correlates. Data obtained at four assessment periods, including enrollment, over a 2-year interval were collected between days 1 and 6 (mean = 3.9) of the menstrual cycle. The primary outcome measure was subjects' rating of sleep quality at each assessment period. Associations of sleep quality with hormone levels (estradiol, follicle-stimulating hormone, luteinizing hormone, testosterone, and dehydroepiandrosterone sulfate) and other clinical, behavioral, and demographic variables were examined in bivariable and multivariable analyses.
Results: Approximately 17% of subjects reported poor sleep at each assessment period. Significant independent associations with poor sleep included greater incidence of hot flashes (odds ratio [OR] 1.52; 95% confidence interval [CI] 1.08, 2.12, P =.02), higher anxiety levels (OR 1.03; 95% CI 1.00, 1.06, P =.04), higher depression levels (OR 1.05; 95% CI 1.02, 1.07, P <.001), greater caffeine consumption (OR 1.25; 95% CI 1.04, 1.49, P =.02), and lower estradiol levels in women aged 45-49 (OR 0.53; 95% CI 0.34, 0.84, P =.006), after adjustment for current use of sleep medications.
Conclusion: Both hormonal and behavioral factors were associated with sleep quality. Estradiol levels are an important factor in poor sleep reported by women in the 45-49 age group. Further evaluation of estrogen treatment for poor sleep of women 45 years and older is warranted.