The interplay between age at menopause, insomnia, and cognitive health: A population-based study (P1-6.001)

Objective: To examine associations between age at menopause, insomnia, and long-term cognitive function among US women. Background: Female sex hormones are postulated to have long-lasting neuroprotective effects. However, the influence of sleep on this association has been insufficiently studied. Design/Methods: We utilized 2008–2016 data from the Health and Retirement Study, a nationally representative cohort of US adults age 50+. In a cohort restricted to women, age at menopause was retrieved from baseline (2008). Prevalence of insomnia in 2010 was identified from self-reported items on trouble falling asleep, nighttime awakenings, early morning awakenings, and use of sleep aids. Cognitive function was assessed biennially using a composite score of immediate and delayed trials of a 10-item word recall test, serial sevens subtraction test, and backwards counting test (range: 0–27). Women with normal cognitive function (score 12–27) and natural transition to menopause were included. Longitudinal associations between age at menopause and cognitive function were estimated with mixed effects models with a random intercept; subsequent models with interaction terms examined whether insomnia moderated the menopause-cognition associations. Results: Among 4,708 women, 23% reported early menopause (age<=45). Over eight years, women who transitioned early to menopause had a mean follow-up cognitive score that was nearly three points lower than those who transitioned to menopause after age 45 (p<.0001). This association was moderated by insomnia, such that women with insomnia had worse cognitive decline. In stratified analyses within ethnoracial groups, Black women who experienced early menopause had the highest rate of cognitive decline (beta=-4.0