Experiential avoidance and anxiety sensitivity as dispositional variables and their relationship to the adjustment to chronic pain.

Anxiety sensitivity has been included in the fear-avoidance model as a vulnerability factor to explain individual differences in fear of pain. Several studies have suggested that the relationship between anxiety sensitivity and some psychopathological disorders is mediated by experiential avoidance, an affect-related regulatory process that involves unwillingness to endure private experiences. The role of these constructs as vulnerability variables has not been investigated in chronic pain patients. The aim of this study was to investigate the role of anxiety sensitivity and experiential avoidance as dispositional variables in pain fear-avoidance. Two alternative hypothetical models were tested: one in which anxiety sensitivity and experiential avoidance would be independently associated with pain fear-avoidance; and second, one in which experiential avoidance would mediate the relationship between anxiety sensitivity and pain fear-avoidance. The sample was composed of 299 patients with chronic back pain. The postulated relationships were tested using LISREL 8.20 software (Scientific Software International, Chicago, IL, USA) and the generally weighted least squares. The structural equation modelling analyses showed that experiential avoidance and anxiety sensitivity were independently associated with pain fear-avoidance and that anxiety sensitivity had a stronger association with pain fear-avoidance than experiential avoidance. The alternative model, in which experiential avoidance mediates the relationship between anxiety sensitivity and pain fear-avoidance, gave a much worse fit. These results highlight the importance of both anxiety sensitivity and experiential avoidance as variables which could explain individual differences in pain fear-avoidance. Thus, in terms of prevention, it should be a priority to identify patients with increased anxiety sensitivity and experiential avoidance during the first stages of the development of chronic pain conditions.