Cognitive function and cannabis use in first episodes of psychosis

Introduction The association between cannabis use and cognitive functioning in individuals experiencing a first episode of psychosis (FEP) is inconsistent, with some studies reporting deterioration (Bogaty et al. J Psychiatr Res 2018; 99:22-32), others indicating improved performance (Rodríguez-Sánchez et al. Schizophr Res 2010; 124:142-151), and some finding no difference. Objectives This study aims to evaluate the effect of cannabis use on cognitive functioning among individuals diagnosed with FEP. Methods A cross-sectional study was conducted on FEP patients enrolled in the ITPCan Program (Santander, Spain) between January 2020 and July 2024. A total of 207 participants (57 cannabis users and 145 non-users) with a FEP diagnosis were included. A descriptive-univariate analysis was performed on clinical, analytical, and cognitive variables. A Student’s t-test compared baseline cognitive performance between cannabis users and non-users, while a multivariate general linear model (GLM) assessed differences related to cannabis consumption, adjusting for sex, age, and educational level. Statistical analyses were performed using SPSS. Results Out of the 207 FEP participants, 53.6% were women, with an average age of 36.8 years. Cannabis users comprised 28.1% of the group, and present at baseline a lower mean age at intake (27 years; p < 0.001). Cannabis users exhibited significantly higher scores in mania and positive psychotic symptoms. Cognitive assessments, completed by 148 patients (39 users and 108 non-users), revealed that cannabis users performed better than non-users on “processing speed” task; however, after adjusting for sex, age, and educational level, these differences were attributed to educational level and sex. Conclusions In consonance with some previous studies (Sánchez-Gutiérrez et al. Eur Psychiatry 2020; 63(1)), cannabis use does not appear to be a determining factor in cognitive performance in early psychosis. Disclosure of Interest None Declared