Emotion regulation, distress tolerance, and experiential avoidance in adults with Trichotillomania (hair-pulling disorder) and excoriation (skin-picking) disorder.

Trichotillomania (TTM) and skin-picking disorder (SPD) are body-focused repetitive behavior disorders (BFRBDs) associated with deficits in emotion regulation, distress tolerance, and experiential avoidance. Their differential relations to TTM, SPD, and their comorbidity, and relative importance in predicting BFRBD outcomes is unclear. Therefore, this study compared these constructs in adults (n = 311) diagnosed with TTM (n = 112), SPD (n = 87), comorbid TTM and SPD (n = 40), and healthy controls (n = 72), and examined their relative importance in association with BFRBD outcomes. Participants completed questionnaires assessing BFRBD severity and impairment, functional disability, emotion regulation, distress tolerance, experiential avoidance, and negative affect. ANOVA was performed to compare groups on these constructs. Hierarchical multiple linear regression analyses were conducted to identify indicators of pulling and picking severity, functional disability, and BFRBD status with statistical adjustment for demographics, negative affect, and comorbid TTM and SPD as appropriate. There were near-convergent patterns of emotion regulation, distress tolerance, and experiential avoidance deficits for BFRBD groups relative to controls, with no differences between BFRBD groups. When controlling for covariates, emotion regulation, distress tolerance, and experiential avoidance were not associated with hair-pulling outcomes or functional disability. Distress tolerance (appraisal) was a significant indicator of total skin picking score, and distress tolerance (appraisal and absorption) and emotion regulation (suppression) were significant indicators of skin picking-related impairment. Experiential avoidance was a significant indicator of BFRBD status. Findings highlight convergence of mechanistic targets across BFRBDs, demonstrate no additive effect of comorbid TTM and SPD on deficits, and suggest interventions targeting experiential avoidance may be particularly helpful.