Sex differences in treatment outcomes among U.S. service members with comorbid PTSD and MDD

Abstract Background Posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) are prevalent and deleterious conditions that commonly co-occur among service members. Identifying factors such as sex that could be linked to treatment response among service members with these conditions is critical for improving care delivery. Methods This study examined sex differences in treatment outcomes among U.S. active duty service members with comorbid PTSD and MDD ( N = 94; 55% women, 45% men) in a randomized controlled trial comparing behavioral activation-enhanced cognitive processing therapy (BA + CPT) and standard CPT. PTSD and MDD symptom severity was assessed at pretreatment, posttreatment, and 3-month follow-up. Results Intent-to-treat multilevel models indicated treatment condition moderated the relationship between sex and PTSD symptoms ( p = .020) but not depression ( p = .16). On average, Clinician-Administered PTSD Scale for DSM-5 scores decreased significantly more among servicewomen who received CPT versus BA + CPT at posttreatment ( p = .004) and 3-month follow-up ( p = .049). There were no significant differences in outcomes among servicemen ( p s > 0.05). In CPT, servicewomen reported significantly greater PTSD symptom reduction compared to servicemen at posttreatment ( p = .039) but not at follow-up ( p = .088). In BA + CPT, PTSD symptoms did not significantly differ between sexes at posttreatment ( p = .054) or follow-up ( p = .29). Conclusions Findings suggest sex may differentially impact outcomes for CPT but not BA + CPT among service members with PTSD and MDD and could help inform shared decision-making between patients and providers. Trial registration ClinicalTrials.gov registry; registration number NCT02874131; date of registration: 08-22-2016.