Modification Effect of Job Demand and Contingent Work Schedule on Overweight and Obesity Among Civil Servants in Taiwan.

ABSTRACT

Objective: Evidence indicated that shift work is a contributing factor to risk of obesity and leads to cardiovascular diseases (CVDs), but few researches have examined the moderating effects of job demand and contingent work schedule on overweight and obesity. Thus, we assessed the modification effect of contingent work schedules and job demand on overweight and obesity among Taiwan's civil servants. Methods: Multistage stratified random cluster sampling was used based on a proportional probabilistic sampling (PPS) in a national survey for civil servants. A total of 20,046 participants from 647 registered governmental institutions were enrolled and anonymously and voluntarily filled out web-based questionnaires. Results: Compared to fixed work schedule, odd ratios (ORs) of obesity and overweight were 1.63 and 1.78 times in contingent work schedule, respectively. In addition, the modification effects of contingent work schedule and high job demand on overweight and obesity with Rothman's synergy index were 2.43 and 2.56, respectively. Using a hierarchical regression model adjusted for covariates, both high job demand and contingent work schedule were interactively associated with overweight and obesity compared to low job demand and fixed work schedule. Conclusion: Since precarious schedules affect employee's obesity through work-related stress and unhealthy behaviors, further research is needed to determine whether interventions aimed at modification of work schedule may be useful in combating obesity.