Cannabis use, self-perceived risk, perceived peer approval and parental attitudes among youth at clinical high-risk for psychosis

Aim: Cannabis use is associated with greater likelihood of psychosis. The relationship between attitudes about cannabis and use has not been examined in youth at clinical high-risk (CHR) for psychosis. Additionally, the shifting legal landscape can provide a valuable context for evaluating use and related attitudes. Methods: This study included 174 participants (44 CHR, 43 healthy control [HC] youth-parent dyads). Youth completed measures of self-reported cannabis use confirmed with a urinalysis, self-perceived risk and perceived peer attitudes. Parents reported attitudes about youth use. Legalization occurred halfway during a 5-year study in Colorado, providing an opportunity to cross-sectionally examine its role in use and attitudes. Results: Frequency of youth reporting cannabis use was significantly higher in CHR (69%) than control group (30%). Use in CHR group was associated with higher perceived peer approval (r =.57), increased parental permissiveness (r =.28) and lower self-perceived risk (r = −.26). Comparing samples participating pre and post-legalization, use remained stable within each group. Group differences in parental permissiveness shifted; trend toward decrease in permissiveness in CHR group (η²_partial =.07) and a significant increase in HCs (η²_partial =.16) were observed. Post-legalization, use in CHR group correlated with higher perceived peer approval (r =.64), lower self-perceived risk (r = −.51) and higher parental permissiveness (r =.35, trend). Conclusions: Taken together, results indicate a relationship between self and peer/parental attitudes about cannabis and use in youth at CHR for psychosis. These factors are important to consider within the legalization context given the changes in parental attitudes and a stronger association between use and attitudes in this group post-legalization.