Racial differences in the effects of hypertension and obesity on health expenditures by diabetes patients in the US

Using a representative sample of US diabetes patients with comorbid hypertension and obesity, we estimate the determinants of health care expenditures. The hypothesis is that the presence of comorbid obesity and hypertension is associated with higher expenditures in the health care system. We are unaware of any study that examines the effects of these conditions taken together. The results confirm our hypothesis. For all races/ethnicities, the addition of hypertension and/or obese to diabetes substantially increases health care expenditures: by over 25% for whites, by over 70% for Blacks and by over 48% for Hispanics. We further find that interactions of obesity and hypertension with race indicate lower health expenditures by minorities compared to whites having the same combination of conditions. Diabetic-obese-not-hypertensive blacks spend 37.7% ($4224 per year) less than their white counterparts. Diabetic-obese-not-hypertensive Hispanics spend 41% ($4591 per year) less than diabetic-obese-not-hypertensive whites. Blacks and Hispanics who are diabetic but not obese or hypertensive spend $5923 and $6409 less than whites with equivalent conditions. The results have implications for efficiency and equity in the health care system.