To Örebro University

Background: Psychiatric diagnoses are important risk factors for criminal convictions, but few longitudinal studies have examined comorbidity patterns in relation to youth criminal convictions.

Aim: To explore associations between specific psychiatric diagnoses (substance use disorder (SUD), ADHD, depression, PTSD, intellectual disabilities (ID), and autism spectrum disorders (ASD)) and comorbidities of internalizing, externalizing, or neurodevelopmental diagnoses (NDD) in relation to risk of non-violent or violent criminal convictions in youth, including potential sex differences.

Methods: Data on 1,411,538 individuals born in Sweden (1985–1998) were obtained from national population-based registers. Exposure was psychiatric diagnoses and outcome was criminal convictions between ages 15 and 20.

Results: 17% of individuals had a psychiatric diagnosis, of whom 20% were convicted of a crime. All diagnoses, except ID and ASD, increased the risk of non-violent and violent crimes. Comorbidities of externalizing and internalizing diagnoses heightened the risk compared to single diagnoses. NDD increased the risk among SUD, depression, and PTSD, while NDD comorbid with another NDD decreased the risk for criminal convictions.

Conclusion: Of the three comorbidity categories, externalizing disorders heightened risk the most, followed by internalizing disorders. This study highlights specific risk patterns for criminal convictions related to comorbidities, and to crime type and sex.

Background: Youth offenders have a high risk of being injured or dying prematurely. However, few studies have considered the role of imprisonment and potential childhood risk factors for these high rates.

Aim: To examine the risk of unintentional injury and premature death in non-imprisoned and imprisoned youth offenders, and to examine the role of parental criminal convictions and psychiatric disorders and own childhood psychiatric disorders.

Methods: All individuals (N = 1,839,711) born in Sweden between 1978 and 1996 were identified using Swedish population-based registers. The exposure was criminal conviction between ages 15-20 years of age.

Results: Imprisoned youth offenders had the highest risk for unintentional injury (HR = 2.29 [2.19-2.40]) and premature death (HR = 10.76 [9.52-12.16]), followed by nonimprisoned youth offenders, compared to non -convicted youth. All childhood risk factors increased the risk for these outcomes among non-imprisoned youth offenders. Among imprisoned youth offenders, parental criminal convictions and parental psychiatric disorders increased the risk for unintentional injury, and parental psychiatric disorders and own childhood psychiatric disorders increased the risk for premature death.

Conclusions: Our study shows there are robust modifiable childhood risk factors for injury and mortality among youth offenders. However, the importance of them to assess risk may differ between non-imprisoned and imprisoned youth offenders.