Anxiety sensitivity as a transdiagnostic risk factor and mechanism of change in the treatment of youth anxiety disorders and OCD: Findings from the Unified Protocols for Transdiagnostic Treatment of Emotional Disorders in Children and Adolescents.

Anxiety sensitivity, or fear of anxiety-related symptoms, is a "core dysfunction" associated with the development and maintenance of youth anxiety disorders and obsessive-compulsive disorder (OCD). Accordingly, anxiety sensitivity is a common target of transdiagnostic cognitive behavioral therapy (CBT) interventions, like the Unified Protocols for Transdiagnostic Treatment of Emotional Disorders in Children and Adolescents (UP-C/A). However, no studies have empirically evaluated anxiety sensitivity as a mechanism of symptom change within UP-C/A treatment. This study examined anxiety sensitivity among a clinical sample of 583 youth ages 8-18 with anxiety disorders and/or OCD who received transdiagnostic CBT treatment with the UP-C/A. At pre-treatment, greater anxiety sensitivity was associated with greater symptom severity across diagnostic categories. This relationship was strongest for panic disorder symptoms. After treatment with the UP-C/A, both anxiety sensitivity and anxiety disorder symptoms decreased. Through lagged mediation analysis, we found that reductions in anxiety sensitivity at one timepoint predicted reductions in anxiety disorder symptoms at the subsequent timepoint. These findings suggest that anxiety sensitivity is a transdiagnostic risk factor and a potential mechanism of change in the treatment of youth anxiety disorders and OCD with the UP-C/A.