State and Trait Disgust Uniquely Predict Avoidance in Contamination Fear: Specificity of Disease-Specific and Nonspecific Individual Differences

Abstract

Although behavioral avoidance is observed among those with heightened contamination concerns, the extent to which such avoidance is best predicted by state and/or trait characteristics is unclear. Furthermore, while disgust proneness is a disease-specific trait that has been shown to predict avoidance among those with symptoms of contamination-based obsessive-compulsive disorder (OCD), it is unclear if other disease-specific traits may also serve a similar function. In the present study, contamination-fearful participants (N = 89) first completed self-report measures of disease-specific (disgust proneness, health anxiety, perceived vulnerability to disease) and disease-nonspecific (intolerance of uncertainty, trait anxiety) traits. They then completed a 16-step behavioral approach task (BAT) with increasing likelihood of contagion in a public restroom and provided ratings of state disgust and state anxiety at each step. Bayesian hierarchical logistic regression showed that state disgust, but not state anxiety, at a given step was associated with avoidance on the next step. Furthermore, disgust proneness was the only trait associated with avoidance on the BAT. A significant interaction between disgust proneness and BAT step completed in the public restroom was also found. Examination of this interaction suggests that intermediary, but not initial and latter, steps of the BAT differentiate those high and low in disgust proneness. These findings suggest that state and trait disgust uniquely drive behavioral avoidance among those with contamination concerns commonly observed in OCD.