Comorbid depression is associated with increased health care use and expenditures in individuals with diabetes.

OBJECTIVE: This study ascertained the odds of diagnosed depression in individuals with diabetes and the relation between depression and health care use and expenditures. RESEARCH DESIGN AND METHODS: First, we compared data from 825 adults with diabetes with that from 20,688 adults without diabetes using the 1996 Medical Expenditure Panel Survey (MEPS). Second, in patients with diabetes, we compared depressed and nondepressed individuals to identify differences in health care use and expenditures. Third, we adjusted use and expenditure estimates for differences in age, sex, race/ethnicity, health insurance, and comorbidity with analysis of covariance. Finally, we used the Consumer Price Index to adjust expenditures for inflation and used SAS and SUDAAN software for statistical analyses.
RESULTS: Individuals with diabetes were twice as likely as a comparable sample from the general U.S. population to have diagnosed depression (odds ratio 1.9, 95% CI 1.5-2.5). Younger adults (<65 years), women, and unmarried individuals with diabetes were more likely to have depression. Patients with diabetes and depression had higher ambulatory care use (12 vs. 7, P < 0.0001) and filled more prescriptions (43 vs. 21, P < 0.0001) than their counterparts without depression. Finally, among individuals with diabetes, total health care expenditures for individuals with depression was 4.5 times higher than that for individuals without depression ($247,000,000 vs. $55,000,000, P < 0.0001).
CONCLUSIONS: The odds of depression are higher in individuals with diabetes than in those without diabetes. Depression in individuals with diabetes is associated with increased health care use and expenditures, even after adjusting for differences in age, sex, race/ethnicity, health insurance, and comorbidity.