(PS2-88) The Role of Comorbidity in Hair-pulling and Skin-picking Behaviors

Hair-pulling (HP) and skin-picking (SP) are common body-focused repetitive behaviors (BFRB), which can lead to serious impairment and distress. HP and SP frequently co-occur and share commonalities in symptom presentation, phenomenology, and genetic underpinnings. However, there is a lack of research examining the comorbidity between HP and SP. Given the high relatedness between two BFRBs, it is important to study the differences between individuals who engage in singular HP/SP or both HP and SP in order to 1) elucidate characteristics that are specific to HP or SP, and 2) understand the unique characteristics associated with comorbid HP and SP. We analyzed a dataset of 1641 college students, who completed an online survey about their BFRBs and Depression, Anxiety, and Stress scale (DASS-21). A total of 578 students reported a current or past engagement in excessive HP, SP, or both. Of those, 176 students (M[SD] = 19.18 [2.03]) were categorized into the HP only group, 349 students were in the SP only group (M[SD] = 19.24 [2.31]), and 53 students were in the comorbid HP and SP group (M[SD] = 19.38 [2.26]). An independent samples t-test was run to examine the differences in symptom severity, behavioral pattern, motivation, and consequences related to HP between HP only vs comorbid HP and SP groups. Another t-test was run to examine the differences between SP only vs comorbid HP and SP groups. A one-way ANOVA was conducted to examine the group differences between HP, SP only vs comorbid HP and SP on DASS-21 subscales, which was followed by Bonferroni post-hoc comparisons after a significant F-test result. Results showed that there were no statistically significant differences between HP only and comorbid HP and SP groups across all indices. However, there were statistically significant differences between SP only and comorbid HP and SP groups in SP symptom severity, t(396) = -3.29, p = .002, d = .64, SP reduced tension t(394) = -4.12, p < .001, d = .62, SP gave relief/gratification t(394) = -3.24, p = .001, d = .50, and SP performed in trance t(394) = -2.67, p = .008, d = .41. For one-way ANOVA, there were significant group differences in Depression F(2, 565) = 5.49, p = .004, Anxiety F(2, 565) = 3.54, p = .030, and Stress F(2, 565) = 4.60, p = .010. Compared to HP only, the comorbid HP and SP group scored higher on Depression t(223) = -2.16, p = .006, d = 4.4. Compared to SP only, the comorbid HP and SP group scored higher on Depression t(393) = -3.30, p = .001, d = .49, Anxiety t(392) = -2.72, p = .007, d = .41, and Stress t(393) = -3.11, p = .002, d = .46. Results demonstrated that individuals who engage in both HP and SP might not have distinct differences from those who engage in HP only. However, compared to those who engage in SP only, individuals who engage in both HP and SP might experience more emotional distress, severe SP symptoms, more reduced tension and relief/gratification as a result of SP, and perform SP more in trance. Hence, this suggests that comorbid HP and SP might increase risk for psychopathology, exacerbate symptoms of SP, and amplify associated behavioral patterns and consequences. More research is warranted to understand the underlying mechanism of such differences. Clinically, HP/SP comorbidity could be useful to identify a possible treatment target (e.g., noticing SP in trance).