Reciprocal changes in functioning and PTSD symptoms over the course of psychotherapy

Psychotherapies for posttraumatic stress disorder (PTSD) assume that PTSD symptom improvement will lead to improvements in functioning. Yet, few studies have examined the dynamic interplay between these constructs. Using a random intercepts cross-lagged panel model, we examined the association between functioning and PTSD, both modeled as a total score and as the DSM-5 subclusters, across twelve sessions of treatments that chiefly target functioning. Participants were 161 Veterans with PTSD enrolled in a randomized controlled trial comparing present centered therapy and an enhanced version of adaptive disclosure. Overall, PTSD symptoms, measured as the total PTSD score, led to changes in functioning more frequently than functioning predicting PTSD symptoms, although these effects did not appear until session 7. In terms of subclusters, functioning predicted changes in the PTSD subclusters B (intrusions), C (avoidance), and E (alterations in arousal and reactivity) at more timepoints compared to timepoints at which these subclusters predicted functioning. The dynamic relationships between PTSD and functioning in the context of functioning-focused treatments are complex, with functioning playing an important role in reduction of some of the core symptoms of PTSD.