Personality Correlates of Self-Injury in Adolescent Girls: Disentangling the Effects of Lifetime Psychopathology.

Adolescent non-suicidal self-injury (aNSSI) is associated with abnormal scores on personality traits, such as high neuroticism. However, no studies to date have examined personality facets of self-injury in a cohort younger than college-age. Plus, adolescent psychopathologies, especially Depressive Disorders, are associated with a similar personality profile and are highly comorbid with aNSSI. Consequently, it remains unclear whether personality provides insights about aNSSI in youth beyond that due to underlying psychopathology. 550 community-dwelling 13- to 15-year-old never-depressed adolescent girls were interviewed for lifetime aNSSI and lifetime psychopathology. Personality traits, broad domains and specific facets, were assessed by self-report. Never-depressed adolescent girls who endorse aNSSI often met lifetime criteria for psychiatric disorders (NSSI: 20/43; 46.5% vs. non-aNSSI: 131/507; 26.1%). aNSSI and lifetime psychopathology were each independently associated with several traits (e.g., high neuroticism and conscientiousness), whereas some traits only discriminated aNSSI (e.g., high melancholia, a facet of neuroticism related to sadness and negative self-evaluation) or lifetime psychopathology independent of each other (e.g., low positive emotionality; low agreeableness). Furthermore, a multivariate model identified high melancholia, high openness to experience, and low conscientiousness as incrementally independent correlates of lifetime aNSSI over and above psychiatric illness. Proneness to melancholia, interest in new things, and poor self-control incrementally track aNSSI in never-depressed adolescent girls. Importantly, this emerges early in course (13-15 years of age) and is independent of lifetime psychiatric diagnosis. Implications for updating etiological models and clinical utility of personality assessment are discussed.