REVIEW OF: Bolhuis K et al, Schizophrenia Bulletin 2024;50(4):881–890

STUDY TYPE: Prospective nationwide cohort study

What happens after a young person presents to the hospital with self-harm? Many recover, but some go on to develop severe mental illnesses, including psychosis. A new large-scale Swedish study explores the relationship between first hospitalization for self-harm and subsequent development of psychosis over 20 years. 

Researchers analyzed data from over 1.4 million individuals born between 1981 and 1993 in Sweden. They identified 28,908 people who presented to the hospital with self-harm (without a prior psychosis diagnosis) and matched them with a cohort without self-harm histories. Participants were followed for up to 20 years to determine their risk of developing psychotic disorders, including schizophrenia and bipolar disorder (BD) with psychotic symptoms.

The primary outcome was the cumulative incidence of psychosis at different time points. The study also examined whether the association between self-harm and psychosis changed over time or by age at first hospital presentation.

The findings were sobering. Among those hospitalized for self-harm, 20.7% developed a psychotic disorder within 20 years—a nearly 14-fold increase in risk compared to individuals with no self-harm history (hazard ratio 13.9). This heightened risk was consistent across birth cohorts and ages at first hospitalization, including those younger than 18, those between 18 and 21, and those older than 21. Gender differences were also notable: 22% of all female psychosis cases had a prior hospitalization for self-harm, compared to 10% of male cases. Half of the psychiatric diagnoses that occurred in this cohort were BD without psychotic features.

CARLAT TAKE

For patients whose self-harm rises to the level of hospitalization, this event is more than just a crisis moment—it’s a warning sign of possible long-term psychiatric risk. The study places these patients on par with those considered “clinical high risk” (CHR) for psychosis, such as individuals with attenuated or prodromal symptoms. Yet unlike CHR populations, those hospitalized for self-harm often receive no follow-up psychiatric care aimed at preventing psychosis. The study’s findings also challenge the tendency to frame self-harm in female patients solely as an emotional regulation issue, as their psychosis risk is just as substantial.

Integrate prevention efforts into emergency and primary care settings to provide opportunities for early intervention. Monitor these patients closely for emerging psychiatric symptoms, especially cognitive decline or social withdrawal, and consider targeted early interventions.