Diagnosis, treatment, comorbidity, and resource utilization of depressed patients in a general medical practice

Objective: The objective of the study was to determine the effect of depression on the utilization of health care resources, after adjusting for age and comorbidity from data obtained on routine clinical practice. Method: The study is an observational cohort of 15,186 patients followed over a one-year period beginning December 1993. Comprehensive demographic, clinical, and utilization data were available from the computerized medical information system generated database of a general internal medicine practice in an urban academic medical center. Results: Four point seven percent of patients carried a provider-coded diagnosis of depression. With regards to utilization of health care resources, even after controlling for age and comorbidity, depressed patients had more primary care visits (5.3 vs. 2.9 visits, p < .001), higher rates of referral to specialists (1.1 vs. 0.5,p < .002), and radiologic tests (0.9 vs. 0.4 tests, p < .001). They had higher total outpatient charges ($1,324 vs. $701,p < .001) and total charges ($2,808 vs. $1,891,p < .001). Depressed patients also had longer length of stay when hospitalized (14.1 vs. 9.5 days, p < .002). Conclusions: Patients diagnosed as depressed had significantly higher resource utilization of all types, even after controlling for the higher burden of comorbid medical illness associated with depression.