Project:
The Economic Impact of Obesity in the South: Assessing Medical Spending Attributable to Obesity

Year: 2004

Research Center: Southern Rural Development Center, Mississippi State University

Investigator: Kolbo, Jerome R., Amal Khoury, and Wendy Bounds

Institution: University of Southern Mississippi

Project Contact:
Jerome Kolbo
College of Health and Human Sciences
University of Southern Mississippi
Box 10075
Hattiesburg, MS 39406
Phone: 601-266-5122
E-mail: Jerome.Kolbo@usm.edu

Summary:

The study objectives were to:

  1. Determine the prevalence of overweight and obesity among adults in the Southern Region of the United States
  2. Estimate the increase in adult per capita medical spending attributable to overweight and obesity
  3. Assess overweight and obesity related healthcare expenses (both in dollars and as a percentage of total spending)
  4. Analyze costs by payer group and sociodemographic groups.
Two nationally representative data sets were used to develop cost estimates: the Medical Panel Survey (MEPS) and the National Health Interview Surveys (NHIS). MEPS is conducted by the Agency for Healthcare Research and Quality (AHRQ). It is a nationally representative survey of civilian non-institutionalized population that collects data about people's healthcare utilization and annual medical spending, including the percentage of spending by out-of-pocket and third-party payers. MEPS contains information about insurance status, region (Northeast, Midwest, South, and West), and sociodemographic variables.

Assessing medical expenditures related to overweight and obesity in the Southern Region can inform policy for food and nutrition assistance programs and strategies to address weight loss and prevent weight gain. In addition, state health departments may use the information to develop new prevention programs appropriate for their populations.

The sampling frame was derived from linking the 1996-2000 MEPS public use file to the records of the same persons in the appropriate years of the NHIS. Height and weight data, necessary to calculate Body Mass Index (BMI), were available for a subset of adult NHIS participants and were merged with the MEPS data. The final sample included adults nineteen years of age and older residing in the Southern Region with weighting variables that allowed generation of regionally representative estimates. Excluded from the analysis were those in the MEPS/NHIS population missing height and weight data, which included all individuals under 18 at the time of the NHIS interview and pregnant women.

A four-equation regression approach was used to predict annual overweight and obesity-attributable medical spending. Variables representing the four BMI categories (underweight, normal, overweight, and obese) were included in the regressions to predict their impact on annual medical spending. All regressions controlled for age, sex, race/ethnicity, income, education, and marital status. Insurance status (i.e., private, Medicaid, Medicare, uninsured) was included to estimate the increase in annual medical spending attributable to overweight and obesity for each insurance category. Prevalence rates were combined with per capita spending estimates, and the percentages of aggregated expenditures attributable to overweight and obesity were computed.

Based on the data analysis, overweight and obesity are pervasive in the Southern Region; prevalence rates are increasing; associated medical costs are significant; expenditures vary by age, gender, race, and payer group; rates are highest among those receiving public assistance; and the greatest increases in expenditures are among private and out-of-pocket payers.

This research provides the first estimates of obesity-related medical costs in the Southern Region. The results can be used to estimate cost savings associated with incremental reductions in the prevalence of obesity in the south. Trends in obesity-related medical spending over time could be determined by comparing future estimates of spending with baseline data from this study.

Findings may be used to develop obesity-related programs by public agencies, private health plans, and employers. Findings may guide policymakers who determine the distribution of limited resources to address obesity prevention or develop policies for food and nutrition assistance programs. Since some of these programs are a source of nutrition education for low-income families, they may play a role in the prevention of obesity.