The Burden of Obesity on Diabetes in the United States: Medical Expenditure Panel Survey, 2008 to 2012

Background: Diabetes is one of the most prevalent and costly chronic diseases in the United States. Objectives: To analyze the risk of developing diabetes and the annual cost of diabetes for a US general population. Methods: Data from the Medical Expenditure Panel Survey, 2008 to 2012, were used to analyze 1) probabilities of developing diabetes and 2) annual total health care expenditures for diabetics. The age-, sex-, race-, and body mass index (BMI)-specific risks of developing diabetes were estimated by fitting an exponential survival function to age at first diabetes diagnosis. Annual health care expenditures were estimated using a generalized linear model with log-link and gamma variance function. Complex sampling designs in the Medical Expenditure Panel Survey were adjusted for. All dollar values are presented in 2012 US dollars. Results: We observed a more than 6 times increase in diabetes risks for class III obese (BMI > 40 kg/m(2)) individuals compared with normal-weight individuals. Using age 50 years as an example, we found a more than 3 times increase in annual health care expenditures for those with diabetes ($13,581) compared with those without diabetes ($3,954). Compared with normal-weight (18.5 < BMI < 25 kg/m(2)) individuals, class II obese (35 < BMI < 40 kg/m(2)) and class III obese (BMI > 40 kg/m(2)) individuals incurred an annual marginal cost of $628 and $756, respectively. The annual health care expenditure differentials between those with and without diabetes of age 50 years were the highest for individuals with class II ($12,907) and class III ($9,703) obesity. Conclusions: This article highlights the importance of obesity on diabetes burden. Our results suggested that obesity, in particular, class II and class III (i.e., BMI > 35 kg/m(2)) obesity, is associated with a substantial increase in the risk of developing diabetes and imposes a large economic burden.