Association Between Cannabis Use and Psychosis-Related Outcomes Using Sibling Pair Analysis in a Cohort of Young Adults

摘要: Context Prospective cohort studies have identified an association between cannabis use and later psychosis-related outcomes, but concerns remain about unmeasured confounding variables. The of sibling pair analysis reduces the influence residual confounding. Objective To explore outcomes. Design A nested within a prospective birth cohort. Setting Births at Brisbane, Australia, hospital. Participants Three thousand eight hundred one young adults born 1981 1984 as part Mater-University Study Pregnancy. Main Outcome Measures Cannabis 3 outcomes (nonaffective psychosis, hallucinations, Peters et al Delusions Inventory score) were assessed 21-year follow-up. Associations duration since first examined using logistic regression adjusted for sex, age, parental mental illness, hallucinations 14-year Within 228 pairs, within-pair differences in score was with general linear modeling. potential impact attrition examined. Results Duration associated all For those 6 or more years, there significantly increased risk (1) nonaffective psychosis (adjusted odds ratio, 2.2; 95% confidence interval, 1.1-4.5), (2) being highest quartile 4.2; 4.2-5.8), (3) 2.8; 1.9-4.1). higher scores on remained associated. Conclusions Early is adults. pairs likelihood that explains these findings. This study provides further support hypothesis early risk-modifying factor Published online March 1, 2010 (doi:10.1001/archgenpsychiatry.2010.6).