Neurocognitive and social cognitive predictors of cannabis use in first-episode psychosis

Background: Findings are unclear as to whether cannabis use is associated with better cognitive functioning in individuals with psychosis. Objectives: To elucidate the association between cannabis use, neurocognition and social cognition in first-episode psychosis (FEP). Methods: Secondary data analysis was conducted on data from 133 FEP participants who had enrolled in a randomized controlled trial of a vocational intervention. Participants completed a neurocognitive and social cognitive battery and characteristics of cannabis use were documented (disorder, recency, frequency and dose). Principal axis factor analysis was used to determine the underlying structure of the cognitive batteries. Regression techniques were used to examine cognitive predictors of current cannabis use disorder (CUD), and recency and frequency of cannabis use. Bivariate correlations were used to examine associations between cognition and dose of cannabis consumption. Results: Male gender (p = .037) was the only significant predictor of having a current CUD. Better processing speed (p = .022) and social cognition (p = .039), male gender (p < .001), and fewer negative symptoms (p = .036) predicted recency of cannabis use. Faster processing speed (p=. 007) and male gender (p=. 006) also predicted frequency of cannabis use. No variables were significantly associated with dose of cannabis consumption. Conclusions: Better social cognition and processing speed abilities predicting recency and frequency of cannabis use are consistent with cannabis users having higher cognitive abilities. A positive relationship between cannabis use and cognition may be the result of more drug taking opportunities in less cognitively impaired individuals with psychosis. (C) 2015 Elsevier B.V. All rights reserved.