Background: Self-injurious thoughts and behaviors are important adverse outcomes among individuals with substance use disorders. Childhood trauma may increase vulnerability to self-harm through emotion dysregulation. This study investigated the mediating role of emotion dysregulation in the association between childhood trauma and self-injurious thoughts and behaviors.
Methods: This descriptive-correlational study employed structural equation modeling. The study population comprised individuals with substance use disorders attending addiction treatment clinics and Narcotics Anonymous groups in Rasht, Iran, in 2026. A total of 385 participants were selected through purposive sampling. Data were collected using the Childhood Trauma Questionnaire (CTQ; 2003), Self-Harm Inventory (SHI; 1998), and Difficulties in Emotion Regulation Scale (DERS; 2004). Data were analyzed using SPSS version 27 and SmartPLS version 3. The significance of the path coefficients and indirect effect was examined using bootstrapping.
Findings: Childhood trauma had significant positive effects on emotion dysregulation (β=0.471, P<0.001) and self-injurious thoughts and behaviors (β=0.112, P=0.030). Emotion dysregulation also had a significant positive effect on self-injurious thoughts and behaviors (β=0.380, P<0.001). The indirect effect of childhood trauma through emotion dysregulation was significant (β=0.179, P<0.001; 95% CI: 0.133–0.235), supporting partial mediation.
Conclusion: Emotion dysregulation partially mediated the association between childhood trauma and self-injurious thoughts and behaviors. Assessing adverse childhood experiences and improving emotion regulation skills may help identify individuals at risk and reduce self-injurious behaviors.