Neurodevelopmental disorders in young violent offenders: Overlap and background characteristics.

Neurodevelopmental disorders (Attention-Deficit/Hyperactivity Disorder (ADHD), Autism Spectrum Disorder (ASD), tic disorder, intellectual disability (ID)), in prison populations have received increased attention but the focus has generally been on one single condition leaving out the global picture. This study assessed the prevalence and overlap of neurodevelopmental disorders (NDD) in a consecutive cohort (n=270) of young adult male offenders (age 18-25 years), sentenced for "hands-on" violent offences and serving prison time in Swedish prisons. Seventy-one percent of all who met inclusion criteria participated. Comprehensive clinical assessments were carried out including history of early antisocial behavior and maladjustment, self-report questionnaires and an intelligence test. Sixty-three percent of the study group met DSM-IV criteria for childhood ADHD, 43% for ADHD in adulthood, 10% met criteria for an ASD, 6% for Tourette syndrome, and 1% for ID. Twenty-two percent had borderline intellectual functioning. A substantial rate of overlap between the NDDs was found. The combined NDD group had an earlier onset of antisocial behavior, had more aggressive behavior and lower school achievements than the non-NDD group. The results highlight the need for prison and probation services to be attentive of and screen for neurodevelopmental disorders in young violent offenders.