Obesity and workers' compensation: results from the Duke Health and Safety Surveillance System

Obese individuals have increased morbidity and use of health services. Less is known about the effect of obesity on workers' compensation. The objective of this study was to determine the relationship between body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared) and number and types of workers' compensation claims, associated costs, and lost workdays.

Retrospective cohort study. Participants included 11 728 health care and university employees (34 858 full-time equivalents [FTEs]) with at least 1 health risk appraisal between January 1, 1997, and December 31, 2004. The main outcome measures were stratified rates of workers' compensation claims, associated costs, and lost workdays, calculated by BMI, sex, age, race/ethnicity, smoking status, employment duration, and occupational group. The body part affected, nature of the illness or injury, and cause of the illness or injury were also investigated. Multivariate Poisson regression models examined the effects of BMI, controlling for demographic and work-related variables.

There was a clear linear relationship between BMI and rate of claims. Employees in obesity class III (BMI >/=40) had 11.65 claims per 100 FTEs, while recommended-weight employees had 5.80; the effect on lost workdays (183.63 vs 14.19 lost workdays per 100 FTEs), medical claims costs ($51 091 vs $7503 per 100 FTEs), and indemnity claims costs ($59 178 vs $5396 per 100 FTEs) was even stronger. The claims most strongly affected by BMI were related to the following: lower extremity, wrist or hand, and back (body part affected); pain or inflammation, sprain or strain, and contusion or bruise (nature of the illness or injury); and falls or slips, lifting, and exertion (cause of the illness or injury). The combination of obesity and high-risk occupation was particularly detrimental.

Maintaining healthy weight not only is important to workers but should also be a high priority for their employers given the strong effect of BMI on workers' injuries. Complementing general interventions to make all workplaces safer, work-based programs targeting healthy eating and physical activity should be developed and evaluated.