Behind the scars: adolescents with non-suicidal self-injury disorder show profound personality pathology

Non-suicidal self-injury is a significant clinical concern in adolescent psychiatry and frequently co-occurs with a range of psychiatric disorders, including mood disorders, eating disorders, substance use disorders, and personality disorders. With the inclusion of non-suicidal self-injury disorder (NSSID) as a distinct diagnosis in the DSM-5, growing attention has been directed toward its relationship with established psychopathological constructs. This study investigates the association between personality pathology and NSSID in adolescent psychiatric in-patients. In particular, we analyzed the prevalence of personality disorders and impairments of personality functioning (identity, self-direction, empathy, intimacy) according to the AMPD of the DSM-5. Our sample consisted of 439 inpatients (mean age = 15.2 years, SD = 1.37; 87 males, 352 females). We used the Structured Clinical Interview for Personality Disorders, the Levels of Personality Functioning questionnaire and the Semi-Structured Interview for Personality Functioning to assess personality pathology, and a structured clinical interview to evaluate the DSM-5 criteria for NSSID. Our results show that adolescents with an NSSID show more severe impairments in all areas of personality functioning and are significantly more likely to be diagnosed with a personality disorder (54%) than adolescents with no NSSID (27%). These results highlight the critical role of personality pathology in adolescents with NSSID and underscore the importance of targeted diagnostic and treatment approaches. Disorder-specific interventions for adolescent personality disorders may also be effective for those with severe NSSI.