# Prevalence and comorbidity of mental disorders among young adults with a history of residential youth care – a two-wave longitudinal study of stability and change

## TL;DR

Young adults with a history of residential youth care have high and stable rates of mental disorders into adulthood, with education completion linked to better outcomes.

## Contribution

This study identifies the long-term stability of mental disorders in former residential youth care participants and highlights education as a protective factor.

## Key findings

- 77.6% of participants had at least one mental disorder at follow-up, showing high stability from adolescence to adulthood.
- Completing high school was the only factor significantly associated with not having a mental disorder diagnosis at follow-up.
- High comorbidity rates were observed, with most participants having multiple mental disorders.

## Abstract

Among youth in residential youth care (RYC) there is a high load of experienced adversities and a high prevalence of mental disorders. Less is known about the stability and change of mental disorders and whether individual or contextual factors that are protective of adult mental disorders could be identified. The current study is a 10-year follow-up of young adults with a history of RYC in Norway. At baseline (T1), 76% met criteria of a mental disorder. At follow-up (T2), diagnostic psychiatric interviews were conducted by phone by experienced doctors and psychologists. A response rate of 52% was achieved (n = 157). Criteria for at least one present mental disorder were fulfilled by 77.6%. The most prevalent single disorders were PTSD (42.1%), agoraphobia (33.3%), social phobia (27.9%), major depressive episode (23.1%), specific phobia (21.1%), and ADHD (19.2%). Most participants had more than one mental disorder. Among those with a diagnosis at T1, completing high school was the only factor found to be associated with no diagnosis at T2 (p = 0.019), whereas no statistically significant association was found with sex, age at first placement and received aftercare. We found a very high prevalence of mental disorders and a high rate of comorbidity comparable to the prevalence at baseline. This shows high stability of psychopathology from adolescence into adulthood. Ensuring access to high quality mental health services for young adults with a history of living in RYC is important. Prevention and early intervention, such as aid to complete education, should be prioritized for young people with high risk of developing mental disorders. Response rate, sample size and selection bias are discussed as possible limitations to the study.

The online version contains supplementary material available at 10.1007/s00406-025-02007-x.