Journal article

The Impact of Cannabis Use on Cognitive Functioning in Patients With Schizophrenia: A Meta-analysis of Existing Findings and New Data in a First-Episode Sample

Murat Yuecel, Emre Bora, Dan I Lubman, Nadia Solowij, Warrick J Brewer, Sue M Cotton, Philippe Conus, Michael J Takagi, Alex Fornito, Stephen J Wood, Patrick D McGorry, Christos Pantelis



Cannabis use is highly prevalent among people with schizophrenia, and coupled with impaired cognition, is thought to heighten the risk of illness onset. However, while heavy cannabis use has been associated with cognitive deficits in long-term users, studies among patients with schizophrenia have been contradictory. This article consists of 2 studies. In Study I, a meta-analysis of 10 studies comprising 572 patients with established schizophrenia (with and without comorbid cannabis use) was conducted. Patients with a history of cannabis use were found to have superior neuropsychological functioning. This finding was largely driven by studies that included patients with a lifetime history of ..

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Awarded by National Health and Medical Research Council (NHMRC) of Australia

Awarded by NHMRC

Funding Acknowledgements

National Health and Medical Research Council (NHMRC) of Australia (Grant 236175, 459111, 514604) and the University of Melbourne; NHMRC Clinical Career Development Awards (Grant 509345/454792 to M.Y. and W.J.B.); Colonial Foundation (to D.I.L.); NHMRC Clinical Career Developmental Award and a National Alliance for Research on Schizophrenia and Depression Young Investigator Award (to S.J.W.); NHMRC CJ Martin Training Fellowship (454797 to A.F.); Ronald Phillip Griffith Fellowship, Faculty of Medicine, Dentistry, and Health Sciences, the University of Melbourne (to S.C.); NHMRC Senior Principal Research Fellowship (628386) and NHMRC Program Grants (350241, 566529 to C.P.); the Leenaards Foundation Switzerland (to P.C.).