Anxiety sensitivity: multiple dimensions and hierarchic structure.

Anxiety sensitivity (AS) is the fear of anxiety-related sensations, based on beliefs that these sensations have harmful consequences. AS is thought to play an important role as a diathesis for anxiety disorders, particularly panic disorder. Recent evidence suggests that AS has a hierarchical structure, consisting of multiple lower-order factors, which load on a single higher-order factor. If each factor corresponds to a discrete mechanism, then the results suggest that AS arises from a hierarchic arrangement of mechanisms. A problem with previous studies is that they were based on the 16-item Anxiety Sensitivity Index (ASI), which may not contain enough items to reveal the type and number of lower-order factors. Accordingly, we developed the 60-item Anxiety Sensitivity Profile, which was administered to 349 university students. Factor analyses revealed four lower-order factors: (1) Fear of respiratory symptoms, (2) fear of cognitive dyscontrol, (3) fear of gastrointestinal symptoms, and (4) fear of cardiac symptoms. These loaded on a single higher-order factor. The lower-order factors shared variance with the higher-order factor, but also contained unique variance. Thus, the results suggest that AS is the product of a general factor, with independent contributions from four specific factors.