Mediating Role of Depression Severity in the Relationship Between Childhood Trauma and Non-Suicidal Self-Injury Among Adolescents With Mood Disorders

Objective: Non-suicidal self-injury (NSSI) frequently co-occurs with childhood trauma (CT) and depression; however, their interplay and underlying mechanisms are not fully understood. This article explores the nuanced relationships between these factors and their impact on NSSI, offering practical insights for the prevention and intervention of childhood post-traumatic depression progression and NSSI among adolescents. Methods: The present study leveraged the Childhood Trauma Questionnaire (CTQ), the Adolescent Non-suicidal Self-injury Assessment Questionnaire (ANSAQ), and the Hamilton Rating Scale for Depression (HAMD) to assess a cohort of 361 individuals with mood disorders. The study design was cross-sectional, and a convenience sampling method was utilized. The mediation effect was tested using the Process stepwise regression method, and the significance of the mediation effect was assessed through Bootstrap analysis. Results: Among 361 adolescents with mood disorders, 232 (64.3%) exhibited NSSI behaviors. Analyses revealed that CT was directly associated with NSSI (beta = 0.312, p < 0.001) and indirectly associated through mediation pathways (beta = 0.256, p < 0.001). CT also showed direct association with depression severity (beta = 0.400, p < 0.001). Depression severity was significantly associated with NSSI (beta = 0.184, p = 0.042), suggesting a partial mediating role of depression severity in this relationship. Conclusions: CT shows a significant association with NSSI among adolescents with mood disorders, with depression severity serving as a partial mediator in this relationship. Active coping strategies targeting depressive symptoms in individuals with a history of CT may help reduce NSSI behaviors.