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
Diego Quattrone, Ulrich Reininghaus, Anne Richards, Giada Tripoli, L. Ferraro, A. Quattrone, Paolo Marino, Victoria Rodriguez, Edoardo Spinazzola, Charlotte Gayer‐Anderson, Hannah E. Jongsma, Peter B. Jones, Caterina la Cascia, Daniele la Barbera, Ilaria Tarricone, E. Bonora, Sarah Tosato, Antonio Lasalvia, Andreı̈ Szöke, Celso Arango, Miquel Bernardo, Julio Bobes, C. M. del Ben, P. Menezes, P. Llorca, J. Santos, Julio Sanjuán, Manuel Arrojo, Andrea Tortelli, Eva Velthorst, S. Berendsen, Lieuwe de Haan, Bart P. F. Rutten, Michael T. Lynskey, Tom P. Freeman, James B. Kirkbride, Pak C. Sham, M. O’Donovan, Alastair G. Cardno, Evangelos Vassos, Jim van Os, C. Morgan, Robin Murray, C. Lewis, Marta Di Forti, Kathryn Stephanie Simona A. Mara David Marta Rapado Álvaro Hubbard Beards Stilo Parellada Fraguas Castro Andr, Kathryn Hubbard, Stephanie Beards, Simona A. Stilo, Mara Parellada, D. Fraguas, M. Castro, Á. Andreu-Bernabeu, Gabriel Lopez, Mario Matteis, Emiliano González, Manuel Durán-Cutilla, Covadonga M Díaz-Caneja, Pedro Cuadrado, José Juan Rodríguez Solano, Angel Carracedo, Javier Costas, Emilio Sánchez, Sílvia Amoretti, Esther Lorente-Rovira, Paz Garcia-Portilla, Estela Jiménez-López, Nathalie Franke, Daniëlla S. van Dam, Fabian Termorshuizen, Els van der Ven, Elles Messchaart, Marion Leboyer, Franck Schürhoff, Stéphane Jamain, Grégoire Baudin, Aziz Ferchiou, Baptiste Pignon, J. Richard, Thomas Charpeaud, A. Tronche, Flora Frijda, Giovanna Marrazzo, Lucia Sideli, Crocettarachele Sartorio, Fabio Seminerio, C. Loureiro, Rosana Shuhama, Mirella Ruggeri, Chiara Bonetto, Doriana Cristofalo, Domenico Berardi, M. Seri, Giacomo D’andrea
Translational Psychiatry August 10, 2021 DOI: 10.1038/s41398-021-01526-0 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 1,596 |
| Population | First-episode psychosis patients and controls from the EU-GEI study |
| Topics | Cannabis |
| Key findings | Schizophrenia polygenic risk score was associated with negative and positive symptom dimensions in first-episode psychosis patients and with all psychotic experience dimensions in controls; daily and current cannabis use were associated with positive dimensions beyond genetic risk. |
Abstract
Diagnostic categories do not completely reflect the heterogeneous expression of psychosis. Using data from the EU-GEI study, we evaluated the impact of schizophrenia polygenic risk score (SZ-PRS) and patterns of cannabis use on the transdiagnostic expression of psychosis. We analysed first-episode psychosis patients (FEP) and controls, generating transdiagnostic dimensions of psychotic symptoms and experiences using item response bi-factor modelling. Linear regression was used to test the associations between these dimensions and SZ-PRS, as well as the combined effect of SZ-PRS and cannabis use on the dimensions of positive psychotic symptoms and experiences. We found associations between SZ-PRS and (1) both negative (B = 0.18; 95%CI 0.03–0.33) and positive (B = 0.19; 95%CI 0.03–0.35) symptom dimensions in 617 FEP patients, regardless of their categorical diagnosis; and (2) all the psychotic experience dimensions in 979 controls. We did not observe associations between SZ-PRS and the general and affective dimensions in FEP. Daily and current cannabis use were associated with the positive dimensions in FEP (B = 0.31; 95%CI 0.11–0.52) and in controls (B = 0.26; 95%CI 0.06–0.46), over and above SZ-PRS. We provide evidence that genetic liability to schizophrenia and cannabis use map onto transdiagnostic symptom dimensions, supporting the validity and utility of the dimensional representation of psychosis. In our sample, genetic liability to schizophrenia correlated with more severe psychosis presentation, and cannabis use conferred risk to positive symptomatology beyond the genetic risk. Our findings support the hypothesis that psychotic experiences in the general population have similar genetic substrates as clinical disorders.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |
Citations in the library
Cites 4
- Daily use of high-potency cannabis is associated with more positive symptoms in first-episode psychosis patients: the EU-GEI case–control study Psychological Medicine March 18, 2020
- Review of the Endocannabinoid System Biological Psychiatry: Cognitive Neuroscience and Neuroimaging August 1, 2020
- The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case-control study The Lancet Psychiatry May 1, 2019
- Just say 'know': how do cannabinoid concentrations influence users' estimates of cannabis potency and the amount they roll in joints? Addiction October 2014