3 - (IOP 16) Comorbid OCD and Anxiety Disorders in Trichotillomania and Skin Picking Disorder: A Systematic Review and Meta-analysis

Introduction:

Body-focused repetitive behavior (BFRB) disorders, including trichotillomania (TTM) and skin picking disorder (SPD), involve repetitive, compulsive behaviors that cause significant distress or impairment. Anxiety disorders and obsessive-compulsive disorder (OCD) commonly co-occur with BFRBs, but reported comorbidity rates vary widely across studies, limiting our understanding of their true prevalence and clinical significance. This meta-analysis aimed to estimate the pooled prevalence rates of current and lifetime OCD and anxiety disorders in individuals with TTM or SPD.

Methods:

Following PRISMA guidelines, we conducted a systematic search of PsycINFO, PubMed, and Web of Science through April 2024. Eligible studies reported current or lifetime prevalence of OCD or anxiety disorders in individuals with TTM or SPD, using DSM or ICD criteria assessed via structured diagnostic tools or clinical interviews. Random-effects meta-analyses estimated pooled prevalence rates with 95% confidence intervals (CIs), employing the Freeman-Tukey double arcsine transformation. Subgroup analyses tested differences in comorbidity rates between TTM and SPD.

Results:

The search yielded 3,539 records, with 85 studies ultimately meeting inclusion criteria. Among these, 64 studies reported on current comorbidities (N=5,328 participants), and 35 studies reported on lifetime comorbidities (N=3,484 participants). Most studies used DSM-IV criteria (71.8%), involved treatment-seeking samples (57.6%), and predominantly included female (84%) and white/Caucasian (85%) participants. The mean sample age was 29.2 years (SD=9.53).

The most prevalent current comorbid anxiety disorders were generalized anxiety disorder (GAD; 19.2%, 95% CI: 16-23), OCD (12.8%, 95% CI: 10-16), social anxiety disorder (10.6%, 95% CI: 8-13), specific phobia (9.3%, 95% CI: 7-12), and agoraphobia (7.1%, 95% CI: 3-15). Lifetime prevalence rates followed a similar pattern, with GAD (22.4%, 95% CI: 17-28), specific phobia (14.5%, 95% CI: 10-20), OCD (13.8%, 95% CI: 9-20), social anxiety disorder (11.0%, 95% CI: 8-15), and panic disorder (8.5%, 95% CI: 6-12) being the most common.

Subgroup analyses revealed that lifetime OCD prevalence was significantly higher in TTM (22.0%) than in SPD (10.1%). Lifetime PTSD was also more prevalent in TTM (11.9%) than in SPD (4.8%).

Discussion:

This meta-analysis highlights the high prevalence of OCD and anxiety disorders in individuals with TTM and SPD, with GAD, OCD, and social anxiety disorder being the most common. These findings underscore the necessity for routine screening of OCD and anxiety disorders in clinical settings for individuals with TTM and SPD. Shared etiological factors, including emotion dysregulation, genetic vulnerability, and neurobiological features, may contribute to these comorbidities; future research should investigate these potential underlying mechanisms. Additionally, nuanced differences in comorbidity patterns between TTM and SPD (i.e., higher OCD and PTSD in TTM) suggest the need for future research investigating these distinct relationships.