Developmental cascades among self-harm, other-harm, and emotion dysregulation in adolescents: a longitudinal within-person analysis of gender differences.

Self-harm (e.g., self-cutting) and other-harm (e.g., hitting/punching someone else) are common dysregulated behaviors during adolescence and sometimes co-occur. Although emotion dysregulation is consistently linked to both behaviors, it is unclear how these behaviors and emotional dysregulation interact over time within individuals or whether their relationships derive from stable influences between individuals. Gender differences in these dynamics are also poorly understood. This study investigated the cascading effects between self-harm, other-harm, and emotion dysregulation and their shared antecedents, with a focus on potential gender differences. The study utilized 4-wave longitudinal data from a community sample of 1,459 adolescents (56.7% boys, aged 11-16 at baseline, M = 12.64 years). Self-harm, other-harm, and emotion dysregulation were assessed four times, with intervals of approximately half a year between assessments. Shared risk factors including familial and school factors were measured at baseline. Data were analyzed using random-intercept cross-lagged panel models, with gender differences examined. The results revealed gender-specific patterns. In girls, self-harm predicted subsequent other-harm, and both behaviors exacerbated emotion dysregulation over time. In boys, self-harm predicted emotion dysregulation, and other-harm influenced self-harm via emotion dysregulation. Interparental conflict and peer victimization were robust predictors of stable between-person differences in self-harm, other-harm, and emotion dysregulation across both genders. These findings highlighted the importance of distinguishing between- and within-person effects and the need for gender-sensitive interventions targeting emotional and behavioral dysregulation in adolescents with conflict exposure.