Long work hours and adverse health outcomes: Defining a health risk-based threshold for work hour exposure
Long work hours (LWH) have been studied as an independent risk factor for adverse health conditions for more than 50 years. However, no previous study has sought to determine the threshold of work hours beyond which there was evidence of increasing risk of poor health or to describe the functional form of work hours and the risk of cardiovascular disease.^ Data from the Panel Study of Income Dynamics were used to: 1) identify the LWH cut points that best predicted increased risk of poor self-reported general health (SRGH), incident cardiovascular disease (CVD), and incident cancer; and 2) evaluate the presence of a dose-response relationship between work hour duration and the risk of CVD.^ Regarding the selection of the statistically optimized cut points, this study suggests that the work hour threshold of 52 hours of work per week or more, on average, over a minimum of 10 years best predicted increased risk of all three outcomes of interest: poor SRGH (RR: 1.28; 95% CI: 1.06-1.53), incident CVD (RR: 1.42; 95% CI: 1.24-1.63), and incident cancer (RR: 1.62; 95% CI: 1.22-2.17). On the question of a dose-response relationship between work hours and CVD, increasing work hour durations were associated with increased risk of incident CVD across a set of nested, hierarchical logistic regression models. The restricted cubic spline model was determined to best fit the data, the results of which suggested a 33% increase in risk of CVD among individuals working 55 hours per week, on average, for a minimum of 10 years compared to those working 45 hours per week, on average, for the same duration.^ This project is not only the first to identify statistically optimized exposure cut points for LWH that are based on the evidence of health risk, but also offers the first characterization of the dose-response relationship between work hour duration and CVD. These results indicate that LWH could be recognized as a potential risk indicator for poor SRGH, CVD, and cancer, thereby contributing to the growing body of evidence regarding LWH and adverse health outcomes.^
Conway, Sarai Carolyn Harris, "Long work hours and adverse health outcomes: Defining a health risk-based threshold for work hour exposure" (2015). Texas Medical Center Dissertations (via ProQuest). AAI3720076.