Prevalence of depression-PTSD comorbidity: Implications for clinical practice guidelines and primary care-based interventions

BACKGROUND: Compared to those with depression alone, depressed patients with posttraumatic stress disorder ( PTSD) experience more severe psychiatric symptomatology and factors that complicate treatment. OBJECTIVE: To estimate PTSD prevalence among depressed military veteran primary care patients and compare demographic/illness characteristics of PTSD screen-positive depressed patients (MDD-PTSD+) to those with depression alone (MDD). DESIGN: Cross-sectional comparison of MDD patients versus MDD-PTSD+ patients. PARTICIPANTS: Six hundred seventy-seven randomly sampled depressed patients with at least 1 primary care visit in the previous 12 months. Participants composed the baseline sample of a group randomized trial of collaborative care for depression in 10 VA primary care practices in 5 states. MEASUREMENTS: The Patient Health Questionnaire-9 assessed MDD. Probable PTSD was defined as a Primary Care PTSD Screen >= 3. Regression-based techniques compared MDD and MDD-PTSD+ patients on demographic/illness characteristics. RESULTS: Thirty-six percent of depressed patients screened positive for PTSD. Adjusting for sociodemographic differences and physical illness comorbidity, MDD-PTSD+ patients reported more severe depression (P <. 001), lower social support (P <. 001), more frequent outpatient health care visits (P <. 001), and were more likely to report suicidal ideation (P <. 001) than MDD patients. No differences were observed in alcohol consumption, self-reported general health, and physical illness comorbidity. CONCLUSIONS: PTSD is more common among depressed primary care patients than previously thought. Comorbid PTSD among depressed patients is associated with increased illness burden, poorer prognosis, and delayed response to depression treatment. Providers should consider recommending psychotherapeutic interventions for depressed patients with PTSD.