Decreases in Psychological Inflexibility Predict PTSD Symptom Improvement in Inpatient Adolescents

Abstract Background Avoidance of trauma-related stimuli and unhelpful changes in thought patterns are integral to the development and maintenance of posttraumatic stress disorder (PTSD). Psychological inflexibility is a process that includes cognitive fusion (entanglement with unhelpful thoughts and taking one's thoughts as representing reality) and experiential avoidance (avoiding unpleasant thoughts, feelings, and memories). Prior research suggests that individual differences in psychological inflexibility may explain why some trauma-exposed youth develop PTSD. Additionally, decreased inflexibility may contribute to PTSD symptom improvement over the course of treatment, but no prior study has assessed this. We sought to shed light on this by evaluating, among adolescent psychiatric inpatients with PTSD, whether decreases in psychological inflexibility predicted PTSD symptom improvement from admission to discharge. Method Adolescents in an inpatient psychiatric unit completed a structured diagnostic interview at admission in addition to self-report measures of psychological inflexibility and PTSD symptom severity at admission and discharge. Analyses are conducted with adolescents with PTSD (n = 67). Results Greater reductions in psychological inflexibility during treatment predicted significantly greater decreases in PTSD symptom severity. Conclusion Reductions in psychological inflexibility appear to function as a mechanism of PTSD symptom improvement during treatment. Reducing psychological inflexibility may be a means by which PTSD treatments help trauma-exposed youth recover, and future research is needed to elucidate these findings.