C Henquet1, A Rosa, P Delespaul, S Papiol, L Fananás, J van Os, I Myin-Germeys. 1. Department of Psychiatry and Neuropsychology, EURON, Maastricht University Medical Centre, South Limburg Mental Health Research and Teaching Network, Maastricht, The Netherlands. cecile.henquet@sp.unimaas.nl
Abstract
OBJECTIVE: A functional polymorphism in the catechol-o-methyltransferase gene (COMT Val(158)Met) may moderate the psychosis-inducing effects of cannabis. In order to extend this finding to dynamic effects in the flow of daily life, a momentary assessment study of psychotic symptoms in response to cannabis use was conducted. METHOD: The experience sampling technique was used to collect data on cannabis use and occurrence of symptoms in daily life in patients with a psychotic disorder (n = 31) and healthy controls (n = 25). RESULTS: Carriers of the COMT Val(158)Met Val allele, but not subjects with the Met/Met genotype, showed an increase in hallucinations after cannabis exposure, conditional on prior evidence of psychometric psychosis liability. CONCLUSION: The findings confirm that in people with psychometric evidence of psychosis liability, COMT Val(158)Met genotype moderates the association between cannabis and psychotic phenomena in the flow of daily life.
OBJECTIVE: A functional polymorphism in the catechol-o-methyltransferase gene (COMTVal(158)Met) may moderate the psychosis-inducing effects of cannabis. In order to extend this finding to dynamic effects in the flow of daily life, a momentary assessment study of psychotic symptoms in response to cannabis use was conducted. METHOD: The experience sampling technique was used to collect data on cannabis use and occurrence of symptoms in daily life in patients with a psychotic disorder (n = 31) and healthy controls (n = 25). RESULTS: Carriers of the COMTVal(158)Met Val allele, but not subjects with the Met/Met genotype, showed an increase in hallucinations after cannabis exposure, conditional on prior evidence of psychometric psychosis liability. CONCLUSION: The findings confirm that in people with psychometric evidence of psychosis liability, COMTVal(158)Met genotype moderates the association between cannabis and psychotic phenomena in the flow of daily life.