TAKING THE PULSE OF PROLONGED EXPOSURE THERAPY: PHYSIOLOGICAL REACTIVITY TO TRAUMA IMAGERY AS AN OBJECTIVE MEASURE OF TREATMENT RESPONSE.

ABSTRACT

BACKGROUND: Physiological reactivity to trauma-related cues is a primary symptom of PTSD and can be assessed objectively using script-driven imagery paradigms. However, subjective self-reported symptom measures are the most common outcome indices utilized in PTSD treatment trials and clinic settings. We examined physiological reactivity during a short trauma imagery task as an objective index of response to PTSD treatment, optimized for use in routine clinical care settings. METHODS: Participants were 35 male combat veterans receiving prolonged exposure (PE) therapy in a Veterans Affairs outpatient clinic. In addition to traditional subjective self-reported and clinician-rated symptom measures, patients also completed a script-driven imagery task in which heart rate (HR) and skin conductance (SC) were recorded at three assessment points across treatment. We examined changes in subjective symptom measures and objective trauma-specific physiological reactivity over the course of PE, and investigated the association between pretreatment physiological reactivity and treatment response. RESULTS: Patients who completed PE showed significantly diminished HR and SC reactivity to trauma imagery across therapy. Additionally, individuals showing greater trauma-specific HR reactivity at pretreatment showed greater reductions in subjectively reported PTSD symptoms at posttreatment. CONCLUSIONS: Findings support the utility of physiological reactivity during trauma imagery as an objective outcome measure that has the potential to be incorporated into evidence-based PTSD treatment in routine clinical settings, or prospective studies related to the individualization of care at pretreatment.