Trends in Costs of Depression in Adults with Diabetes in the United States: Medical Expenditure Panel Survey, 2004-2011

To investigate differences in healthcare cost trends over 8 years in adults with diabetes and one of four categories of comorbid depression: no depression, unrecognized depression, asymptomatic depression, or symptomatic depression. Data from the 2004-2011 Medical Expenditure Panel Survey (MEPS) was used to create nationally representative estimates. The dependent variable was total healthcare expenditures for the calendar year, including office-based, hospital outpatient, emergency room, inpatient hospital, prescription, dental, and home health care expenditures. The 2004-2011 direct medical costs were adjusted to a common 2014 dollar value. The primary independent variable was four mutually exclusive depression categories created from ICD-9-CM codes and the PHQ-2 depression screening tool. Healthcare expenditures were estimated using a two-part model and were adjusted for age, sex, race, marital status, education, health insurance, metropolitan statistical area status, region, income level, and comorbidities. Based on a national sample of adults with diabetes (unweighted sample of 15,548, weighted sample of 17,465,579), 10.2 % had unrecognized depression, 13.6 % had asymptomatic depression, and 8.9 % had symptomatic depression. In the pooled sample, after adjusting for covariates, the incremental cost of unrecognized depression was $2872 (95 % CI 1660-4084), asymptomatic depression increased by $3347 (95 % CI 2568-4386), and symptomatic depression increased by $5170 (CI 95 % 3610-6731) compared to patients with no depression. Adjusted analyses showed that expenditures were $2000-3000 higher for unrecognized and asymptomatic depression than no depression, and $5000 higher for symptomatic depression. Higher medical expenditures persisted over time, with only symptomatic depression showing a sustained decrease over time.