Experiential avoidance and anxiety sensitivity in patients with panic disorder and agoraphobia: Do both constructs measure the same thing?

We examined whether Anxiety Sensitivity (AS) and Experiential Avoidance (EA), two potentially relevant constructs in the evolution of anxiety and related disorders with significant implications for cognitive-behavioral treatments, differentially relate to symptom expressions of patients with panic disorder and agoraphobia. Within a multi-center study 369 patients meeting the DSM-IV-TR criteria for panic disorder with agoraphobia (PD/AG) completed the multidimensional Panic and Agoraphobia Scale (PAS), the Anxiety Sensitivity Index (ASI), the Acceptance and Action Questionnaire- II (AAQ-II) and the Beck Depression Inventory-II (BDI-II). Overlap, distinctiveness, and predictive validity of AS and EA were examined using explorative item analyses and multiple hierarchical regression analyses. AS and EA moderately correlated with each other (r=-.50, p<.01). EA explained additional variance in PAS-subscales Anticipatory Anxiety and Panic-Related Disability, but not in Panic Attacks, Agoraphobic Avoidance and Health Worries. ASI, AAQ-II and BDI-II explained a low to moderate amount of variation in the five PAS-subscales (R2 =.04-.29; p<.005). AS and EA are overlapping, yet distinct constructs. Results suggest that EA contributes to a significantly improved understanding of vulnerability, at least in patients with PD/AG.