Mean Levels and Variability in Psychological Well-Being and Associations With Sleep in Midlife and Older Women

Background Disturbed sleep is prevalent in older adulthood and particularly among women. Greater psychological well-being (PWB) is associated with better sleep, but intraindividual variability in PWB has not been examined. Purpose The current study examined whether mean levels and variability in PWB were associated with sleep disturbances in midlife and older women. Methods Participants (N = 189) completed up to seven daily diaries and an end of the week assessment every 3 months for nine waves. Participants answered questions about their nightly sleep disturbances and reported their PWB using Ryff's six dimensions of PWB. Results Regression models indicated that greater variability in one aspect of PWB, positive relations with others, was related to greater sleep disturbance even after adjusting for mean levels of well-being. Greater variability in environmental mastery, purpose in life, and self-acceptance were also associated with sleep disturbance, but these associations were no longer significant after adjusting for mean levels of well-being. Conclusions Results suggest that fluctuations in positive relations with others are related to sleep in adult women above and beyond mean levels of well-being. Results highlight the importance of considering variability in addition to mean levels of PWB.