Statistical predictors of psychosocial impairment in body-focused repetitive behaviors.

Background: Skin picking disorder and trichotillomania, also characterized as body-focused repetitive behaviors (BFRBs), often lead to functional impairment. Some people with BFRBs, however, report little if any psychosocial dysfunction. There has been limited research as to which clinical aspects of BFRBs are associated with varying degrees of functional impairment.
Methods: Adults (n = 98), ages 18 to 65 with a current diagnosis of trichotillomania (n = 37), skin picking disorder (n = 32), trichotillomania plus skin picking disorder (n = 10), and controls (n = 19) were enrolled. Partial least squares regression (PLS) was used to identify variables associated with impairment on the Sheehan Disability Scale.
Results: PLS identified an optimal model accounting for 45.8% of variation in disability. Disability was significantly related to (in order of descending coefficient size): severity of picking, perceived stress, comorbid disorders (specifically, anxiety disorders / obsessive-compulsive disorder), trait impulsivity, family history of alcohol use disorder, atypical pulling/picking sites, and older age.
Conclusions: At present mental disorders are viewed as unitary entities; however, the extent of impairment varies markedly across patients with BFRBs. These data suggest that whereas symptom nature/severity is important in determining impairment, so too are other variables commonly unmeasured in clinical practice. Outcomes for patients may thus be maximized by rigorously addressing comorbid disorders; as well as integrating components designed to enhance top-down control and stress management. Interestingly, focused picking and emotional pulling were linked to worse disability, hinting at some differences between the two types of BFRBs, in terms of determinants of impairment.