Cannabis use and schizotypy: the role of social anxiety and other negative affective states.

Emerging research suggests that cannabis use might be related to psychosis onset in people vulnerable to developing schizophrenia-spectrum disorders. Furthermore, individuals with high-positive and disorganized schizotypy traits report more cannabis use and cannabis-related problems than controls. Social anxiety, a frequently co-occurring schizotypal feature, is related to increased cannabis-related problems in the general population. Building on this research, we explored the impact of social anxiety, measured by the Social Interaction Anxiety Scale (SIAS), and depression and trait anxiety reported on the Brief Symptom Inventory (BSI), on the relationship of schizotypy, measured by the Schizotypy Personality Questionnaire-Brief Revised (SPQ-BR), to cannabis use (n=220 schizotypy, 436 controls) and frequent use and cannabis-related problems among users (n=88 schizotypy, 83 controls) in college undergraduates. Among cannabis users, social anxiety moderated the relationships of schizotypy to frequent cannabis use and more cannabis-related problems in the total schizotypy group, and across high-positive, negative, and disorganized schizotypy subgroups. Depression and trait anxiety also moderated the relationship of schizotypy to frequent cannabis use and more cannabis-related problems, but results varied across high-positive, negative, and disorganized schizotypy subgroups. Results suggest therapeutically targeting negative affective states may be useful in psychosocial intervention for cannabis-related problems in schizotypy.