Background: Evidence on the causal relationship between working overtime and the risk of coronary heart disease is limited.
Methods: We surveyed 2355 workers in Japan and conducted propensity-matched logistic regression analysis, using propensity-matched 438 pairs, to evaluate the associations between working overtime (more than 50 hr per week) and coronary risk factors: physical inactivity, cigarette smoking, sleep deprivation (<5 hr/day), psychological stress, overweight/obesity, and excessive alcohol consumption. The exposure and outcomes were self-reported.
Results: Among 2355 workers, 476 participants worked overtime. Propensity-matched analysis revealed that the associations between working overtime and sleep deprivation (odds ratios (OR) and 95% confidence intervals: 2.33, 1.39-3.88) and high stress (2.13, 1.60-2.82). The associations between working overtime and physical inactivity, current smoking, and overweight/obesity were not statistically significant. Excessive alcohol consumption was inversely associated with working overtime.
Conclusions: Working overtime was positively associated with two coronary risk factors: sleep deprivation and increased psychological stress.
Keywords: cigarette smoking; excessive alcohol consumption; obesity; overweight; physical inactivity; psychological stress; sleep deprivation.
© 2015 Wiley Periodicals, Inc.