THE RELATION OF THE PSYCHOSIS CONTINUUM WITH SCHIZOPHRENIA POLYGENIC RISK SCORE AND CANNABIS USE

Schizophrenia polygenic risk score and cannabis use modify psychosis expression in first episode psychosis patients and population controls

AbstractBackgroundDiagnostic categories within the psychosis spectrum are widely used in clinical practice, however psychosis may occur on a continuum. Therefore, we explored whether the continuous distribution of psychotic symptoms across categories is a function of genetic as well as environmental risk factors, such as polygenic risk scores (PRSs) and cannabis use.MethodsAs part of the EU-GEI study, we genotyped first episode psychosis patients (FEP) and population controls, for whom transdiagnostic dimensions of psychotic symptoms or experiences were generated using item response bi-factor modelling. Linear regression was used, separately in patients and controls, to test the association…

S118. TRANSDIAGNOSTIC SYMPTOM DIMENSIONS OF PSYCHOSIS AND THE PREDICTIVE ROLE OF PREMORBID ADJUSTMENT AND COGNITIVE CHARACTERISTICS IN THE MULTINATIONAL EU-GEI STUDY

Abstract Background A symptom dimension approach may best examine the heterogeneous expression of psychosis. However, whether and how premorbid predisposition and cognitive factors explain phenotypes variation is still debated. This study aimed to test the predictive value of combined cognition and premorbid adjustment on transdiagnostic symptom dimensions in a large sample of people suffering from the first episode of psychosis (FEP). Methods FEP patients were part of the EUGEI study. Psychopathology was rated using the OPerational CRITeria system. Multidimensional item response modelling estimate a bifactor model of psychosis by Mplus, composed of a general factor and five specific sympto…

TRANSDIAGNOSTIC SYMPTOM DIMENSIONS OF PSYCHOSIS AND THE PREDICTIVE ROLE OF PREMORBID ADJUSTMENT AND COGNITIVE CHARACTERISTICS IN THE MULTINATIONAL EU-GEI STUDY

S126. THE RELATION OF THE PSYCHOSIS CONTINUUM WITH SCHIZOPHRENIA POLYGENIC RISK SCORE AND CANNABIS USE

Abstract Background There has been much debate about whether research into psychosis should be conducted using symptom dimensions as opposed to diagnostic categories. Indeed, dimensions, like categories, may be practical but arbitrary tools for research and clinical practice; hence, they should not be based on psychometric data only. The aim of this study was to externally validate empirically derived symptom dimensions using combined genetic and environmental data. Specifically, we examined the hypothesis that the continuous multivariate distribution of psychosis is a function of cannabis use and genetic liability to schizophrenia, as summarised by polygenic risk score (SZ-PRS). Methods As…

The continuity of effect of schizophrenia polygenic risk score and patterns of cannabis use on transdiagnostic symptom dimensions at first-episode psychosis: findings from the EU-GEI study

The work was supported by Guarantors of Brain post-doctoral clinical fellowship to DQ; Clinician Scientist Medical Research Council fellowship (project reference MR/M008436/1) to MDF; Heisenberg professorship from the German Research Founda- tion (grant no. 389624707) to UR; the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care. The EU-GEI Project is funded by the European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-…