Identifying men at ultra high risk of psychosis in a prison population.

BACKGROUND

The prevalence of psychotic disorders among prisoners is relatively high. We sought to investigate the prevalence of men who have a very high risk of developing psychosis in a prison population.

METHODS

The Prodromal Questionnaire - Brief Version (Loewy, Pearson, Vinogradov, Bearden and Cannon, 2011), was used to screen newly-arrived prisoners in a London prison for features associated with an increased risk of psychosis. Concurrent validity was evaluated using the Comprehensive Assessment for At Risk Mental State (Yung et al., 2005).

RESULTS

750 prisoners were screened and 301 were underwent further clinical assessment. 5% the total number of those screened met diagnostic criteria for the ARMS and 3% had recently developed a first episode of psychosis. Using endorsement of items that also caused distress, the PQ-B predicted an ARMS or a psychotic disorder with 90% sensitivity and 44% specificity.

CONCLUSIONS

The PQ-B is effective in identifying people who are vulnerable to developing psychosis in a prison population.