摘要:Objectives . We estimated health care expenditures associated with overweight and obesity and examined the influence of age, race, and gender. Methods . Using 1998 Medical Expenditure Panel Survey data, we employed 2-stage modeling to estimate annual health care expenditures associated with high body mass index (BMI) and examine interactions between demographic factors and BMI. Results . Overall, the mean per capita annual health care expenditure (converted to December 2003 dollars) was $3338 before adjustment. While the adjusted expenditure was $2127 (90% confidence interval [CI]=$1927, $2362) for a typical normal-weight White woman aged 35 to 44 years, expenditures were $2358 (90% CI=$2128, $2604) for women with BMIs of 25 to 29.9 kg/m 2 , $2873 (90% CI=$2530, $3236) for women with BMIs of 30 to 34.9 kg/m 2 , $3058 (90% CI=$2529, $3630) for women with BMIs of 35 to 39.9 kg/m 2 , and $3506 (90% CI=$2912, $4228) for women with BMIs of 40 kg/m 2 or higher. Expenditures related to higher BMI rose dramatically among White and older adults but not among Blacks or those younger than 35 years. We found no interaction between BMI and gender. Conclusions. Health care costs associated with overweight and obesity are substantial and vary according to race and age. Obesity is the second-leading cause of preventable death in the United States, and it is a major cause of morbidity and disability. 1, 2 Over the past 2 decades, the prevalence of obesity has risen substantially; 64% of Americans are now overweight, and 30% are obese (i.e., have a body mass index [BMI] in excess of 30 kg/m 2 ). 3 This increase has led to concerns about a possible epidemic of adverse health outcomes and their associated economic consequences. Previous researchers have examined the effect of obesity on total health care costs using different methodologies. 4– 8 Some have determined the costs attributable to obesity by estimating people’s likelihood of developing and incurring costs associated with weight-related diseases such as hypertension, diabetes, and heart disease. 4, 6 Others have used cross-sectional data at the individual level to examine health care expenditures among people at different BMI levels. 5– 8 While estimates vary depending on the methodology used and when the study was conducted, the most recent estimates place the excess costs attributable to overweight and obesity at between 4% and 9% of total health care costs. 4– 8 In addition, some studies have shown that these increased costs are associated with more use of health care resources. 5 Few researchers examining the health care costs of obesity, however, consider whether patient demographic factors affect the relationship between BMI and cost. It is generally accepted that there is a dose–response relationship between higher BMIs and increased adverse health consequences, including mortality, 1, 2, 9 but whether this relationship exists for certain race and age subgroups is more controversial. For instance, some studies suggest that the higher risk of death attributable to obesity is blunted—and, in some instances, nonexistent—among African Americans and older adults. 10– 12 Differences in obesity-related disease burden in different demographic populations may lead to differences in obesity-related health care costs. At least one study, involving data gathered in 1987, revealed that health care costs associated with higher BMI rose more steeply among women than men among those with BMIs at above-normal levels. 13 Understanding the influence of demographic factors on the costs attributable to obesity can facilitate accurate projections of future health care costs given that current increases in obesity prevalence rates in the United States disproportionately affect women, Hispanics, and Blacks. 3, 14 In our study, we examined annual per capita health care expenditures associated with overweight and obesity among US adults and assessed the influences of gender, age, and race/ethnicity on this relationship.