Within-Patient Association Between Emotion Regulation and Outcome in Prolonged Exposure for Posttraumatic Stress Disorder

Objective: Difficulties with emotion regulation (ER) are a risk factor for the development and maintenance of posttraumatic stress disorder (PTSD). Less is known about temporal relations between ER and PTSD symptom change during treatment, including whether ER may represent a more potent change ingredient for some patients relative to others. This study examined the association between within-patient changes in ER and next-session PTSD symptom change and whether this association was more pronounced for patients with poorer baseline ER, more severe depression, or higher borderline personality disorder symptoms. Method: Data derived from a randomized controlled trial (NCT01600456) in which 149 adults with PTSD received up to 10 sessions of prolonged exposure (PE) or PE + sertraline. Patients rated difficulties with ER and PTSD symptoms repeatedly during treatment. Moderators were assessed at baseline. Results: Cross-lagged, dynamic structural equation models revealed that ER improvements were associated with next-session reductions in PTSD (standardized effect = 0.13). PTSD symptom reduction was also associated with next-session ER improvement (standardized effect = 0.34). Moderator analyses revealed that the within-person ER-PTSD symptoms association was stronger for patients with higher baseline depression (standardized effect = 0.39). Conclusions: Reductions in PTSD symptoms may facilitate ER improvements during PE and PE augmented with sertraline rather than improvements in ER producing changes in PTSD symptoms. For patients with higher severity co-occurring depression, ER may represent a more active change ingredient. PE therapists could therefore consider placing particular emphasis on improving ER capabilities when working with this subgroup of patients. What is the public health significance of this article? Findings from this study highlight a reciprocal, within-person relation between emotion regulation and PTSD symptoms. However, the effect sizes for these associations indicate that reductions in PTSD symptoms may primarily facilitate ER improvements during PE and PE + sertraline. Moderator analyses revealed that for patients with higher levels of co-occurring depression, ER may represent a more active ingredient that can directly foster symptom reduction.