Association of cumulative childhood adversity and adolescent violent offending with suicide in early adulthood.

Objective  To examine whether adolescent violent offending mediates the association between CA and suicide in early adulthood.

Design, Setting, and Participants  This population-based, longitudinal cohort study with a follow-up time spanning 5 to 9 years included 476 103 individuals born in Sweden between 1984 and 1988. The study population was prospectively followed up from 20 years of age until December 31, 2013, with respect to suicide. Data analysis was performed from January 1, 1984, to December 31, 2013.

Exposures  Register-based CAs included parental death, parental substance abuse and psychiatric disorder, parental criminal offending, parental separation, public assistance recipiency, child welfare intervention, and residential instability. Adolescent violent offending was defined as being convicted of a violent crime between the ages of 15 and 19 years.

Main Outcomes and Measures  Estimates of risk of suicide after 20 years of age (from 2004 if born in 1984 and from 2008 if born in 1988) until the end of 2013 were calculated as incidence rate ratios (IRRs) with 95% CIs using Poisson regression analysis. Adjustments were made for demographics and psychiatric disorder. In addition, binary mediation analysis with logistic regression was used.

Results  A total of 476 103 individuals (231 699 [48.7%] female) were included in the study. Those with a conviction for violent offending had been exposed to all CAs to a greater extent than those with no violent offending. Cumulative CA was associated with risk of suicide in nonconvicted (adjusted IRR, 2.4; 95% CI, 1.5-3.9) and convicted youths, who had a higher risk of suicide (adjusted IRR, 8.5; 95% CI, 4.6-15.7). Adolescent violent offending partly mediated the association between CA and suicide.

Conclusions and Relevance  Individuals with a history of CA who also engage in violent offending in adolescence have a high risk of suicide. Interventions to prevent externalizing behavior during childhood and increased support to youths with delinquent behavior may have the potential to prevent suicide related to CA.