The association between body mass and health care expenditures

With several studies estimating the health care costs attributable to obesity-related medical conditions, the economic consequences of being overweight are beginning to come into focus. The present study complements this growing body of literature by directly estimating health care costs across a broad range of body mass index values. Data were obtained from the 1987 National Medical Expenditure Survey (NMES) public use data tapes and retrospective analyses conducted on NMES Household Survey data only. The analyses included a total of 16,217 individuals between the ages of 18 and 65. Four classes of health care utilization and expenditures were derived using the NMES data: (1) use of any health care service and total health care expenditures, (2) use of inpatient services and inpatient expenditures, (3) use of outpatient services and outpatient expenditures, and (4) use of prescription medication and medication expenditures. Estimates based on our findings suggested strong relationships between body mass and the likelihood of using health care services and between body mass and average annual health care expenditures for both men and women. Increased body mass was associated with increased expenditures. However, this association was greater among males than among females and did not hold for individuals in the lowest body mass category. Ideal body mass was associated with 6.3% to 36.1% lower annual health care expenditures among females and 3.6% to 18.2% lower health care expenditures among males. The results of this set of analyses suggest that health care expenditures increase as weight deviates from the ideal—that is, health care expenditures among both underweight and overweight individuals in the United States were increased in relation to ideal weight. Separate analyses including weight-related diseases such as diabetes and hypertension indicated that body mass increased health care expenditures largely by increasing the risk for these costly chronic medical conditions.