Background: Multiple factors, including patient characteristics, competing demands, and clinic type, impact delivery of depression treatment in primary care.
Objective: Assess whether depression severity and HIV serostatus have a differential effect on time to depression treatment among depressed patients receiving primary care at Infectious Disease or General Medicine clinics.
Design: Multicenter prospective cohort, (Veterans Aging Cohort Study), comparing HIV-infected to uninfected patients.
Participants and measures: The total cohort consisted of 3,239 HIV-infected and 3,227 uninfected patients. Study inclusion criteria were untreated depressive symptoms, based on a Patient Health Questionnaire (PHQ-9) score of greater than 9, and no antidepressants or mental health visits in the 90 days prior to PHQ-9 assessment. Treatment was defined as antidepressant receipt or mental health visit within 90 days following PHQ-9 assessment. Depression severity based on PHQ-9 scores was defined as mild-moderate (greater than 9 to 19) and severe (20 or greater). Kaplan-Meier curves were used to estimate time to treatment by depression severity and HIV serostatus. Cox proportional hazards methods adjusted for covariates were used.
Key results: Overall, 718 (11%) of the cohort met inclusion criteria, 258 (36%) of whom received treatment. Median time to treatment was 7 days [95% confidence interval (CI) = 4, 13] and was shortest for severely depressed HIV-infected patients (0.5 days; 95% CI = 0.5, 6, p = 0.04). Compared to mildly-moderately depressed uninfected patients, severely depressed HIV-infected patients were significantly more likely to receive treatment [adjusted hazard ratio (HR) 1.67, 95% CI = 1.07, 2.60), whereas mildly-moderately depressed HIV-infected patients (adjusted HR 1.10, 95% CI = 0.79, 1.52) and severely depressed uninfected patients (adjusted HR 0.93, 95% CI = 0.60, 1.44) were not.
Conclusions: In this large cohort, time to primary care treatment of depression was shortest among severely depressed HIV-infected patients. Regardless of HIV serostatus, if depression was not treated on the assessment day, then it was unlikely to be treated within a 90-day period, leading to the majority of depression being untreated.