An early intervention for psychosis and its effect on criminal accusations and suicidal behaviour using a matched-cohort design.

BACKGROUND: Early interventions for psychosis have been shown to reduce psychotic symptoms and hospital use for first-episode patients, but the effect on suicidal and criminal behaviour has not been reliably determined. This study aimed to examine whether an early intervention for psychosis program (EPPIS) reduced criminal behaviour, suicide attempts, and hospital-based service use. METHODS: The study utilized administrative data to match clients of EPPIS to historical controls. Regression was used to determine the effect of treatment by EPPIS on inpatient use, emergency department use, suicide attempts/deaths, and criminal accusations. RESULTS: A sample of 244 patients was matched to 449 controls. EPPIS patients had lower odds of being accused of a crime both during and after treatment. Suicidal behavior was less frequent among patients, both during treatment (p<0.0001) and after (HR=0.39; 95% CI: 0.17 to 0.94). During treatment there were more emergency department visits for the patients (RR=2.54; 95% CI: 1.56 to 4.58), but no difference in inpatient usage compared to controls. Post-treatment, both emergency department and inpatient usage were higher among patients. CONCLUSIONS: EPPIS patients had reduced suicide attempts and criminal accusations. Increased emergency department use could indicate that encouraging treatment during a crisis may increase service use, while reducing suicidal and criminal behaviour.