Occupational Shift Work, Sleep Behaviors, and Metabolic Health Disparities: Results from the Survey of the Health of Wisconsin

Background/Objective: The increasing demand for a 24-hour society, exemplified by a departure from the traditional work day, has heightened our risk of acting at odds with the circadian rhythms of optimal cardiovascular or metabolic function. Particularly vulnerable are employees whose jobs require them to work an “alternate shift” (night, flex, extended, or rotating shifts). The objective of this study was to examine shiftworker metabolic health disparities (obesity and/or type 2 diabetes) and assess the influence of disordered sleep on disease prevalence among a population-based sample of employed adults. Methods: This study utilized population-based, cross-sectional data from 913 employed adults in the Survey of the Health of Wisconsin (2008-2010). Data were collected on self-reported shiftwork employment, disordered sleep (i.e. insomnia, functional sleepiness, insufficient sleep) and measured body mass index and hemoglobin A1c. Analyses examined the prevalence of disordered sleep and metabolic health outcomes among shiftworkers vs. traditional workers, and the potential mediating effects of disordered sleep on metabolic health outcomes. Results: Shiftworkers were more likely than their traditional work schedule counterparts to be overweight/obese (80.9% vs. 69.3%, respectively) and to report disordered sleep (e.g. average daily sleep duration of less than seven hours (51.0% vs. 43.3%, respectively)). Disordered sleep significantly increased the odds of obesity and type 2 diabetes, and partially mediated the relationship between shiftwork and prevalent obesity, controlling for age, gender, race/ethnicity, and education. Conclusion: The results of this study support the call for multi-level, occupation-oriented interventions to address the significant disordered sleep and metabolic health disparities for shiftworkers.