Examining the relationship between Body Mass Index, Medical Utilization and Worker Productivity in a Multi-Site Study

Previous studies have examined either direct or indirect costs of worker healthcare utilization and/or absence. The literature suggests there is limited research that provides a comprehensive view of the cost-burden of the effects of overweight and obesity. The goal of this study was to demonstrate the effects of excess weight on direct and indirect employee healthcare costs and productivity across a large sample of diverse employers.

In an NHLBI-funded study, seven academic affiliates were enlisted to engage worksites to participate in a socio-ecological and environmental-based health risk reduction program. Four of the seven research sites pooled baseline characteristics of BMI, healthcare utilization, and productivity measures to examine the characteristics of the working population (N=10,026). We analyzed annual doctor visits, annual emergency room (ER) visits, annual hospital admissions, absenteeism, and “presenteeism” or on-the-job productivity losses to see if using biometric Body Mass Index (BMI) categories [normal (18.0-<25.0), overweight (25.0-<30.0) or obese (>30.0)] had any differential effects. Multivariate count models of negative binomial, Poisson, and zero-inflated Poisson models were used, depending on the volume of zero responses and overdispersion of the data. The models also controlled for other potential confounding variables: age, gender, race/ethnicity, smoking status, education, profession, and research site. Average annual medical expenditures and wage rates used to monetize the utilization and productivity estimates were derived from the MarketScan® Research Database and the Bureau of Labor Statistics.

Workers were approximately evenly distributed across BMI categories; 39% of the sample was obese, and 31% were overweight. Obese employees had higher rates of doctor visits, ER visits, hospital admissions, absenteeism (all p<0.01), and presenteeism (p<0.05) than their normal weight counterparts. Initial comparisons of overweight and normal weight people showed no statistically significant differences. Controlling for other factors, obese employees had higher doctor visits (p<0.01), ER visits (p<0.01), absent days (p<0.01), and presenteeism (p<0.05) than normal weight employees. Analysis of the hospital admissions showed that the actual number of hospital admissions of overweight and obese people was similar to normal people. Overall, there was a $644 estimated increased total cost for obese employees compared to normal employees.

This study corroborates findings of the financial burden that obese and, to some degree, overweight individuals put on employer costs. While there was no significant increase in medical costs or absenteeism for overweight employees, day-to-day job productivity was still affected. Programs targeting weight reduction, specifically moving people from obese to overweight, would be cost-beneficial for employers.