Self-Induced Nail Disorders: Clinical and Demographical Features.

Background: Self-induced nail disorders (SINDs) are a subset of body-focused repetitive behaviors (BFRBs) characterized by pathological grooming habits that damage the nail and periungual structures. These disorders were classified into subgroups based on the specific methods individuals use to harm their nails. Despite their prevalence and potential psychological impact, limited data exist. This study aims to investigate the demographic and clinical characteristics of SINDs.

Methods: This multicenter prospective cohort study included 675 patients diagnosed with SINDs at dermatology outpatient clinics between February and June 2024. Data collected included demographic information, SIND subtypes, associated BFRBs, psychiatric history, and family history of BFRBs. Patients were categorized into six SIND subgroups. Approval from the ethical committee was obtained.

Results: The mean age of SIND onset was 16.60 ± 10.61 years, with no significant gender difference (p = 0.195). Forty-seven percent of patients belonged to more than one SIND subgroup, and 45.4% had other BFRBs, with cheek/lip biting (55.7%) and acne excoriée (44.9%) being the most common. Females exhibited higher rates of accompanying BFRBs (54.5% vs. 31.2%; p = 0.001). Patients rarely sought medical treatment (19.1%), even if they felt severe discomfort regarding their habit (56.0%). Patients with diagnosed psychiatric disorders or a family history of BFRBs were more likely to seek treatment (p = 0.001, p = 0.013).

Conclusion: SINDs often coexist with other BFRBs, predominantly affecting females. While patients are frequently aware of their habits, the rate of seeking medical treatment remains low. Dermatologists play a vital role in identifying SINDs, addressing associated behaviors, and coordinating care for coexisting psychiatric conditions.