Posttraumatic Stress Disorder Symptom Cluster Structure in Prolonged Exposure Therapy and Virtual Reality Exposure.

The emotional processing theory of posttraumatic stress disorder (PTSD) posits that avoidance is central to PTSD development and maintenance. Prolonged exposure (PE) therapy, which clinically focuses on avoidance reduction, has strong empirical support as a PTSD treatment. Virtual reality exposure (VRE) has been utilized to accelerate avoidance reduction by increasing multisensory engagement. Although some exposure therapy studies have found associations between avoidance and PTSD symptoms, others have indicated that reexperiencing or hyperarousal symptoms drive symptom trajectories. Using a cross-lagged panel design, the present secondary data analysis examined temporal associations between clinician-assessed PTSD symptom clusters during treatment with PE, VRE, or a waitlist control condition. There were no significant differences between PE and VRE regarding symptom clusters at any assessment. Compared to the waitlist condition, individuals who received VRE or PE exhibited earlier reductions in avoidance/numbing symptoms, β = -.19, 95% CI [-.33, -.05], followed by reductions in hyperarousal symptoms, β = -.21, 95% CI [-.33, -.09]. Hyperarousal symptoms predicted changes in later avoidance/numbing and reexperiencing outcomes across treatment: pretreatment to midtreatment, β = .29, 95% CI [.17, .42]; midtreatment to posttreatment, β = .23, 95% CI [.07, .39]. Reexperiencing symptoms predicted changes in hyperarousal outcomes earlier in treatment, β = .22, 95% CI [.02, .37], whereas avoidance/numbing symptoms predicted changes in hyperarousal outcomes later in treatment, β = .18, 95% CI [.04, .32]. These findings support the efficacy of exposure therapy in addressing avoidance/numbing symptoms and highlight the potential importance of hyperarousal symptoms in relation to other symptom clusters.