Patterns of premorbid functioning in individuals at clinical high risk of psychosis.

In schizophrenia, four typical patterns of premorbid functioning have been observed: stable-good, stable-intermediate, poor-deteriorating and deteriorating. However, it is unknown whether similar patterns exist in those who are at clinical high risk (CHR) of psychosis. The aim of this study was to examine patterns of premorbid functioning in a large sample of individuals at CHR of psychosis and its association with symptoms, functioning, and conversion to psychosis. One-hundred sixty people at CHR of psychosis were assessed on premorbid functioning using the Premorbid Adjustment Scale. Poorer premorbid functioning was significantly correlated with worse negative symptom severity and lower social functioning. Cluster analysis was used to identify patterns of premorbid functioning. Results indicated three patterns of premorbid functioning in our CHR sample: stable-intermediate, stable-good, and deteriorating. The deteriorating group had more severe disorganization, worse negative symptoms, and poorer social functioning than the other groups. Participants who made the conversion to psychosis had significantly poorer premorbid functioning during adolescence compared to those who did not convert. These results suggest that those at a clinical high risk for psychosis display similar patterns in premorbid functioning as have been observed in those with a psychotic illness and that poor premorbid functioning may be a predictor of psychosis.