Objectives: The aim of this study was to examine the presence of a dose–response relationship between work hours and incident cardiovascular disease (CVD) in a representative sample of U.S. workers.
Methods: A retrospective cohort study of 1926 individuals from the Panel Study of Income Dynamics (1986 to 2011) employed for at least 10 years. Restricted cubic spline regression was used to estimate the dose–response relationship of work hours with CVD.
Results: A dose–response relationship was observed in which an average workweek of 46 hours or more for at least 10 years was associated with an increased risk of CVD. Compared with working 45 hours per week, working an additional 10 hours per week or more for at least 10 years increased CVD risk by at least 16%.
Conclusion: Working more than 45 work hours per week for at least 10 years may be an independent risk factor for CVD.