Detection of substance use disorders in patients presenting with depression

Comorbidity between substance use disorders and major depression may complicate the treatment and adversely affect the outcome of either disorder. This study examines the frequency with which patients presenting with depression are evaluated for a substance use disorder in a university-based family medicine residency program. A retrospective chart review was performed to identify 200 patients age 18 and older, seen between June 1, 1989, and June 1, 1999, who were diagnosed with depression (DSM IV code 300.4 or 311.0). The records were divided into two strata based on whether they were seen by resident or faculty physicians. The records were then reviewed for evidence of substance use screening. The overall percentage of patients with depression and evaluated for substance use disorders was calculated, and further stratified as to gender, age, previous psychiatric diagnosis, and previous substance use disorder diagnosis. Family physicians evaluated outpatients with a diagnosis of depression for substance use disorders only 24.5% of the time. Faculty evaluated depressed patients 18%, compared to residents doing so in 31% of patients. Male patients were evaluated 34.7% as compared to 21.2% of females. Patients over age 70 were screened at a rate of only 10.7%. Given the observed prevalence of substance use disorders in patients with a diagnosis of depression is between 40 and 50%, our finding that our depressed patients were evaluated for substance use disorders only 24.5% of the time, suggests that family physicians may be missing a significant number of patients with comorbid disease.