GOLDILOCKS AT WORK: JUST THE RIGHT AMOUNT OF JOB DEMANDS MAY BE NEEDED FOR YOUR SLEEP HEALTH

Abstract Objectives It has been reported that job demands affect sleep, but how different levels of job demands affect sleep remains unclear. We examined whether curvilinear relationships exist between job demands and multiple sleep health outcomes. Design: Cross-sectional analyses with linear and quadratic effects, using self-administered survey data. Setting: A national sample of U.S. adults. Participants: Workers from Midlife in the United States Study (MIDUS2; n=2,927). Measurements: The Job Content Questionnaire assessed overall and five specific aspects of job demands (intensity, role conflict, work overload, time pressure, and interruptions). Habitual sleep health patterns across five dimensions (regularity, satisfaction/quality, daytime alertness, efficiency, and duration) were assessed. Age, sex, race/ethnicity, marital/partnered status, education, job tenure, work hours, body mass index, smoking status, and study sample were covariates. Results There were significant linear and quadratic relationships between job demands and sleep outcomes. Specifically, the linear effects indicated that higher job demands were associated with degraded sleep health, such as shorter duration, greater irregularity, greater inefficiency, and more dissatisfaction. The quadratic effects, however, indicated that the rate of degrade was decelerated in terms of sleep regularity and efficiency, such that these sleep outcomes were best with moderate levels of job demands. These effects were found for overall job demands as well as specific aspects of job demands. Stratified analyses further revealed that these curvilinear associations were mainly driven by participants with low job control. Conclusions Moderate levels of job demands, especially if combined with adequate job control, are related to better sleep health.