The role of depression in the maintenance of gains after a prolonged exposure intensive outpatient program for posttraumatic stress disorder.

Abstract

Intensive outpatient programs (IOPs) for trauma-focused therapy, such as prolonged exposure (PE), have the potential to deliver highly effective treatment, quickly and with minimal dropout. Identifying factors that predict maintenance of gains after treatment can help triage individuals who may need additional services. Growth mixture modeling (GMM) was used to identify classes of posttraumatic stress disorder (PTSD) and depression symptom trajectories across the year following a 2-week IOP, delivering daily PE for PTSD for post-9/11 Veterans. Predictors of trajectories were examined. Three classes of trajectories best-fit the data for PTSD and depression symptoms. Two classes made up the majority of the sample (85%) and both maintained significantly reduced PTSD symptoms across the year following therapy. For a minority of the sample (14.6%), PTSD symptoms rebounded after treatment. These individuals were highly likely to be categorized in the persistent depression class. IOP-delivered PE is effective, and gains are largely maintained. The minority of patients who do not maintain their gains as robustly are likely to report persistent depressive symptoms in treatment and higher PTSD symptoms on a self-report measure.