Shift workers, defined as those who work at night, rotating or other alternate shifts, undertake an occupational health risk of growing importance as this nontraditional schedule becomes more common. Evidence suggests shift work may even play a role in increasing or perpetuating socioeconomic-related health disparities.
“Compared to those who work traditional schedules, employees who work shifts outside of the normal nine-to-five are more likely to be men, minorities, or individuals of lower socioeconomic status,” said Marjory Givens, lead author of the study and associate scientist at the University of Wisconsin-Madison School of Medicine and Public Health. “We found that shift workers are prone to sleep problems and poor cardiometabolic health including obesity and diabetes, and that the chances of being overweight were even greater for shift workers who did not get enough sleep. This suggests that the adverse metabolic implications of working shifts could be alleviated by getting enough sleep.”
The study, published in the journal Sleep Health, examined occupational, sleep behavior and metabolic health data from the 1,593 participants in the Survey of the Health of Wisconsin. The study found that shift workers were more likely to be overweight than traditional-schedule workers (83 percent vs 71 percent with a body mass index of 25 or more) and reported more sleep problems such as insomnia (24 percent vs 16 percent), insufficient sleep (53 percent vs 43 percent) and sleepiness (32 percent vs 24 percent).
Since shiftwork and sleep problems have both been implicated in poor metabolic health, this study asked whether sleep problems may play a role in shift worker health disparities. Givens and colleagues found that even though sleep problems did not fully explain the association between shift work and being overweight or diabetic, these associations appeared to be stronger among shift workers who were not able to obtain sufficient sleep (less than seven hours per day).
“We need people doing these jobs so the question is: what should be done about maintaining or improving their health? People who do shift work likely do not have the same opportunities to be healthy because if you work at night and sleep through the day, you’re not going to have the same options for undisturbed sleep, access to healthy foods or venues for physical activity that people who work traditional hours have,” said Javier Nieto, senior author and principal investigator of the study, and chair of the UW Department of Population Health Sciences. “Most gyms, grocery stores, restaurants, and other venues have schedules that complement the 9-5 work schedule.”
According to study authors, the findings warrant further exploration and interventions to improve workplace wellness initiatives that address the persistent and prevailing health disparities that shift workers face. The study also suggests that primary health care providers should consider their patients’ occupational history. In patients who work in nontraditional hours, providers may need to evaluate the need for targeted screening and educational efforts to alleviate the potential deleterious effects of shift work.
“Observational studies can’t prove causality, but there is enough evidence – from our study and many others like it – to suggest that shift work may negatively affect health,” said Nieto. “If businesses are interested in the health of their workers, finding cost-effective ways for employees to be healthier while continuing to work nontraditional hours would be mutually beneficial for workers and employers. Heightening awareness about the occupational policies or business practices that influence the choices employees can make and improving behaviors and sleep patterns can all positively impact the health of our workforce.”
University of Wisconsin School of Medicine and Public Health