Better knowledge about childhood trauma as a risk factor for psychiatric disorders in young people could help strengthen the timeliness and effectiveness of prevention and treatment efforts.

To estimate the prevalence and risk of psychiatric disorders in young people following exposure to childhood trauma, including interpersonal violence.

This prospective cohort study followed 8199 adolescents (age range 12–20 years) over 13–15 years, into young adulthood (age range 25–35 years). Data about childhood trauma exposure from adolescents participating in the Trøndelag Health Study (HUNT, 2006–2008) were linked to data about subsequent development of psychiatric disorders from the Norwegian Patient Registry (2008–2021).

One in four (24.3%) adolescents were diagnosed with a psychiatric disorder by young adulthood. Regression analyses showed consistent and significant relationships between childhood exposure to both interpersonal violence and other potentially traumatic events, and subsequent psychiatric disorders and psychiatric comorbidity. The highest estimates were observed for childhood exposure to two or more types of interpersonal violence (polyvictimisation), and development of psychotic disorders (odds ratio 3.41, 95% CI 1.93–5.72), stress and adjustment disorders (odds ratio 4.20, 95% CI 3.05–5.71), personality disorders (odds ratio 3.98, 95% CI 2.70–5.76), alcohol-related disorders (odds ratio 3.28, 95% CI 2.06–5.04) and drug-related disorders (odds ratio 4.67, 95% CI 2.87–7.33).

These findings emphasise the importance of integrating knowledge about childhood trauma as a potent risk factor for psychopathology into the planning and implementation of services for children, adolescents and young adults.