Adolescent Victimization and Self-Injurious Thoughts and Behaviors: A Genetically Sensitive Cohort Study.

OBJECTIVE: Victimized adolescents have elevated risk of self-injurious thoughts and behaviors. However, poor understanding of causal and non-causal mechanisms underlying this observed risk limits the development of interventions to prevent premature death among adolescents. We tested whether pre-existing family-wide and individual vulnerabilities account for victimized adolescents' elevated risk of self-injurious thoughts and behaviors.

METHOD: Participants were 2,232 British children followed from birth to age 18 as part of the Environmental Risk (E-Risk) Longitudinal Twin Study. Adolescent victimization (maltreatment, neglect, sexual victimization, family violence, peer/sibling victimization, cyber-victimization, and crime victimization) was assessed through interviews with participants and co-informant questionnaires at the age 18 assessment. Suicidal ideation, self-harm, and suicide attempt in adolescence were assessed through interviews with participants at age 18.

RESULTS: Victimized adolescents had an increased risk of suicidal ideation (Odds Ratio [OR]= 2.40, 95% CI=2.11-2.74), self-harm (OR=2.38, 95% CI=2.10-2.69), and suicide attempt (OR=3.14, 95% CI=2.54-3.88). Co-twin control and propensity-score matching analyses showed that these associations were largely accounted for pre-existing familial and individual vulnerabilities, respectively. Over and above their prior vulnerabilities, victimized adolescents still showed a modest elevation in risk for suicidal ideation (OR=1.36, 95%CI=1.06-1.76) and self-harm (OR=1.50, 95% CI=1.18-1.91), but not suicide attempt (OR=1.28, 95% CI=0.83-1.98).

CONCLUSION: Risk for self-injurious thoughts and behaviors in victimized adolescents is only partly explained by the experience of victimization. Pre-existing vulnerabilities account for a large proportion of the risk. Therefore, effective interventions to prevent premature death in victimized adolescents should not only target the experience of victimization but also address pre-existing vulnerabilities.