Health care utilization and costs of depressed veterans with comorbid PTSD

Background: Depressed patients with comorbid posttraumatic stress disorder (PTSD) have greater functional impairment than patients with depression alone, but few studies have assessed the association of comorbid PTSD with health care utilization and costs. Objective: To evaluate whether depressed patients who screen PTSD positive (PTSD+) have greater health care utilization and costs than PTSD negative (PTSD-) patients. Methods: A cross-sectional comparison of utilization rates and costs over 12 months. Administrative data were taken from a randomized trial of collaborative care treatment for depression in nine Veterans Affairs (VA) primary care clinics across five states (N=674). Majority were white men over 55. Suicidal or bipolar screen positive patients were excluded. Results: Thirty-six percent of the patients were PTSD+ using the Primary Care-PTSD screen. PTSD+ depressed patients had more frequent mental health visits 6.9 vs. 1.7 (P<.001), and more total outpatient visits 26.2 vs. 19.9 (P<.001) than PTSD- patients, without adjustment. A higher proportion of PTSD+ depressed patients were prescribed antidepressants than PTSD- patients. PTSD+ patients had correspondingly higher mental health, outpatient, and antidepressant costs than PTSD- patients. Primary care and inpatient utilization and costs were not significantly different between the two groups. Results remained the same after adjustment for confounders. Conclusions: Veterans with depression who screen PTSD+ have higher utilization and costs of total outpatient services, mental health services, and antidepressants than PTSD- depressed patients. If new veterans coming into the VA system have high rates of PTSD, mental health treatment costs are likely to increase.