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.