Cannabis use correlates with schizotypy in healthy people.

Cannabis use or high scores on self-report schizotypy questionnaires predict an increased risk of developing clinical psychosis. We tested whether cannabis use correlated with schizotypal and other personality traits in 211 healthy adults. Subjects who had used cannabis showed higher scores on schizotypy, borderline and psychoticism scales than never-users. Multivariate analysis, covarying lie scale scores, age and educational level indicated that high schizotypal traits best discriminated subjects who had used cannabis from never-users, whether or not they reported having used other recreational drugs. These results indicate that cannabis use is related to a personality dimension of psychosis-proneness in healthy people.