Avoidance Moderates Cognitive Behavioral Therapy for Panic Disorder and Agoraphobia

Abstract
Cognitive behavioral therapy (CBT), a well-validated treatment for panic disorder, includes interoceptive exposures and possibly in vivo exposures to agoraphobic situations. Testing predictors and moderators of CBT outcomes can improve treatment efficacy. Sixty-six individuals with panic disorder with or without agoraphobia were randomized to panic control therapy (PCT) (n = 32) or PCT and in vivo exposures to agoraphobic situations (PCT + IV) (n = 34). Secondary analyses using multilevel models with repeated measures design revealed that individuals who displayed more interoceptive avoidance and agoraphobic avoidance fared better after PCT than PCT + IV compared with individuals who displayed less avoidance. Results suggest that these individuals benefit from concentrated doses of exposures to their primary interoceptive concerns instead of additional exposures to agoraphobic situations. Exploratory analyses were also conducted on fear, demographic factors, and clinical characteristics. Findings inform clinical decision-making and personalized medicine. Limitations include low power for detecting small effect sizes.