Abstract
We conducted a systematic review of meta-analyses and systematic reviews to evaluate the impact of cannabis use on the onset and course of psychoses. Following a systematic literature search of five data bases (2005–2016) and consecutive structured evaluation, we were able to include 26 systematic reviews and meta-analyses. The methodological quality of the included publications were in the range of high and poor. The scientific literature indicates that psychotic illness arises more frequently in cannabis users compared to non-users, cannabis use is associated with a dose-dependent risk of developing psychotic illness, and cannabis users have an earlier onset of psychotic illness compared to non-users. Cannabis use was also associated with increased relapse rates, more hospitalizations and pronounced positive symptoms in psychotic patients. We make recommendations about the type of research that is required to better characterize the relationship between cannabis use and the development and outcomes of psychosis.
Similar content being viewed by others
References
Barkus E, Lewis S (2008) Schizotypy and psychosis-like experiences from recreational cannabis in a non-clinical sample. Psychol Med 38:1267–1276
Gage SH, Hickman M, Zammit S (2016) Association between cannabis and psychosis: epidemiologic evidence. Biol Psychiatry 79:549–556
Martin-Santos R, Crippa JA, Batalla A et al (2012) Acute effects of a single, oral dose of d9-tetrahydrocannabinol (THC) and cannabidiol (CBD) administration in healthy volunteers. Curr Pharm Des 18:4966–4979
Mechoulam R, Hanus LO, Pertwee R et al (2014) Early phytocannabinoid chemistry to endocannabinoids and beyond. Nat Rev Neurosci 15:757–764
Gage SH, Zammit S, Hickman M (2013) Stronger evidence is needed before accepting that cannabis plays an important role in the aetiology of schizophrenia in the population. F1000 Med Rep 5:2
Hill M (2015) Perspective: be clear about the real risks. Nature 525:S14
Ksir C, Hart CL (2016) Cannabis and psychosis: a critical overview of the relationship. Curr Psychiatry Rep 18:12
Minozzi S, Davoli M, Bargagli AM et al (2010) An overview of systematic reviews on cannabis and psychosis: discussing apparently conflicting results. Drug Alcohol Rev 29:304–317
Di Forti M, Quattrone D, Freeman TP et al (2019) The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case–control study. Lancet Psychiatry 6:427–436
Schoeler T, Monk A, Sami MB et al (2016) Continued versus discontinued cannabis use in patients with psychosis: a systematic review and meta-analysis. Lancet Psychiatry 3:215–225
Burns JK (2013) Pathways from cannabis to psychosis: a review of the evidence. Front Psychiatry 4:128
D’souza DC, Sewell RA, Ranganathan M (2009) Cannabis and psychosis/schizophrenia: human studies. Eur Arch Psychiatry Clin Neurosci 259:413–431
Bersani G, Orlandi V, Kotzalidis GD et al (2002) Cannabis and schizophrenia: impact on onset, course, psychopathology and outcomes. Eur Arch Psychiatry Clin Neurosci 252:86–92
Hartz SM, Pato CN, Medeiros H et al (2014) Comorbidity of severe psychotic disorders with measures of substance use. JAMA Psychiatry 71:248–254
Radhakrishnan R, Wilkinson ST, D’souza DC (2014) Gone to pot—a review of the association between cannabis and psychosis. Front Psychiatry 5:54
Falkai P, Rossner MJ, Schulze TG et al (2015) Kraepelin revisited: schizophrenia from degeneration to failed regeneration. Mol Psychiatry 20:671–676
Schmitt A, Malchow B, Hasan A et al (2014) The impact of environmental factors in severe psychiatric disorders. Front Neurosci 8:19
Bastian H, Glasziou P, Chalmers I (2010) Seventy-five trials and eleven systematic reviews a day: how will we ever keep up? PLoS Med 7:e1000326
Smith V, Devane D, Begley CM et al (2011) Methodology in conducting a systematic review of systematic reviews of healthcare interventions. BMC Med Res Methodol 11:15
Hoch E, Friemel C, Schneider M (2018) Cannabis: Potenzial und Risiko. In: Hoch E, Friemel C, Schneider M (eds) Eine wissenschaftliche Bestandsaufnahme. Springer, Berlin
Äzq (2013) Institut für Medizinisches Wissensmanagement, Ärztliches Zentrum für Qualität in der Medizin. In: “Manual Systematische Literaturrecherche für die Erstellung von Leitlinien”. 1. Auflage 2013. Verfügbar: DCZ: http://www.cochrane.de/de/webliographie-litsuche; AWMF: http://www.awmf.org/leitlinien/awmf-regelwerk/ll-entwicklung.html; ÄZQ: http://www.aezq.de/aezq/publikationen/kooperation
Higgins JPT, Green S (2011) Cochrane handbook for systematic reviews of interventions Version 5.1.0. The Cochrane Collaboration, London
Hall W, Hoch E, Lorenzetti V (2019) Cannabis use and mental health: risks and benefits. Eur Arch Psychiatry Clin Neurosci 269:1–3
Awmf (2012) German Association of the Scientific Medical Societies (AWMF). AWMF-Regelwerk “Leitlinien”. 1. Auflage. In: Standing Guidelines Commission. AWMF guidance manual and rules for guideline development sEEvAahwaola-rh (ed)
Ocebm (2011) Levels of evidence working group. In: Oxford Centre for Evidence-Based Medicine O (ed), 2nd edn
Moher D, Liberati A, Tetzlaff J et al (2009) Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. BMJ 339:b2535
Hemming K, Pinkney T, Futaba K et al (2013) A systematic review of systematic reviews and panoramic meta-analysis: staples versus sutures for surgical procedures. PLoS ONE 8:e75132
Sign (2015) Scottisch intercollegiate guidelines network 50 methodology checklist. Edinburgh, UK
Burns JK (2012) Cannabis use and duration of untreated psychosis: a systematic review and meta-analysis. Curr Pharm Des 18:5093–5104
Koskinen J, Lohonen J, Koponen H et al (2010) Rate of cannabis use disorders in clinical samples of patients with schizophrenia: a meta-analysis. Schizophr Bull 36:1115–1130
Kraan T, Velthorst E, Koenders L et al (2016) Cannabis use and transition to psychosis in individuals at ultra-high risk: review and meta-analysis. Psychol Med 46:673–681
Large M, Sharma S, Compton MT et al (2011) Cannabis use and earlier onset of psychosis: a systematic meta-analysis. Arch Gen Psychiatry 68:555–561
Linscott RJ, Van Os J (2013) An updated and conservative systematic review and meta-analysis of epidemiological evidence on psychotic experiences in children and adults: on the pathway from proneness to persistence to dimensional expression across mental disorders. Psychol Med 43:1133–1149
Marconi A, Di Forti M, Lewis CM et al (2016) Meta-analysis of the association between the level of cannabis use and risk of psychosis. Schizophr Bull 42:1262–1269
Moore TH, Zammit S, Lingford-Hughes A et al (2007) Cannabis use and risk of psychotic or affective mental health outcomes: a systematic review. Lancet 370:319–328
Myles H, Myles N, Large M (2016) Cannabis use in first episode psychosis: meta-analysis of prevalence, and the time course of initiation and continued use. Aust N Z J Psychiatry 50:208–219
Myles N, Newall H, Nielssen O et al (2012) The association between cannabis use and earlier age at onset of schizophrenia and other psychoses: meta-analysis of possible confounding factors. Curr Pharm Des 18:5055–5069
Potvin S, Sepehry AA, Stip E (2007) Meta-analysis of depressive symptoms in dual-diagnosis schizophrenia. Aust N Z J Psychiatry 41:792–799
Potvin S, Sepehry AA, Stip E (2006) A meta-analysis of negative symptoms in dual diagnosis schizophrenia. Psychol Med 36:431–440
Sara GE, Large MM, Matheson SL et al (2015) Stimulant use disorders in people with psychosis: a meta-analysis of rate and factors affecting variation. Aust N Z J Psychiatry 49:106–117
Semple DM, Mcintosh AM, Lawrie SM (2005) Cannabis as a risk factor for psychosis: systematic review. J Psychopharmacol 19:187–194
Szoke A, Galliot AM, Richard JR et al (2014) Association between cannabis use and schizotypal dimensions—a meta-analysis of cross-sectional studies. Psychiatry Res 219:58–66
Baldacchino A, Hughes Z, Kehoe M et al (2012) Cannabis psychosis: examining the evidence for a distinctive psychopathology in a systematic and narrative review. Am J Addict 21(Suppl 1):S88–S98
Ben Amar M, Potvin S (2007) Cannabis and psychosis: what is the link? J Psychoact Drugs 39:131–142
Cookey J, Bernier D, Tibbo PG (2014) White matter changes in early phase schizophrenia and cannabis use: an update and systematic review of diffusion tensor imaging studies. Schizophr Res 156:137–142
Ferretjans R, Moreira FA, Teixeira AL et al (2012) The endocannabinoid system and its role in schizophrenia: a systematic review of the literature. Revista brasileira de psiquiatria 34(Suppl 2):S163–S177
Geoffroy PA, Etain B, Houenou J (2013) Gene × environment interactions in schizophrenia and bipolar disorder: evidence from neuroimaging. Front Psychiatry 4:136
James A, James C, Thwaites T (2013) The brain effects of cannabis in healthy adolescents and in adolescents with schizophrenia: a systematic review. Psychiatry Res 214:181–189
Malchow B, Hasan A, Fusar-Poli P et al (2013) Cannabis abuse and brain morphology in schizophrenia: a review of the available evidence. Eur Arch Psychiatry Clin Neurosci 263:3–13
Rapp C, Bugra H, Riecher-Rossler A et al (2012) Effects of cannabis use on human brain structure in psychosis: a systematic review combining in vivo structural neuroimaging and post mortem studies. Curr Pharm Des 18:5070–5080
Serafini G, Pompili M, Innamorati M et al (2012) Can cannabis increase the suicide risk in psychosis? A critical review. Curr Pharm Des 18:5165–5187
Vera U, Annarita T, Rocco P et al (2013) Cannabis and psychosis: a systematic review of genetic studies. Curr Psychiatry Rev 9:302–315
Zammit S, Moore TH, Lingford-Hughes A et al (2008) Effects of cannabis use on outcomes of psychotic disorders: systematic review. Br J Psychiatry 193:357–363
Gage SH, Jones HJ, Burgess S et al (2017) Assessing causality in associations between cannabis use and schizophrenia risk: a two-sample Mendelian randomization study. Psychol Med 47:971–980
Buchanan RW, Kreyenbuhl J, Kelly DL et al (2010) The 2009 schizophrenia PORT psychopharmacological treatment recommendations and summary statements. Schizophr Bull 36:71–93
DGPPN (2019) S3-Leitlinie Schizophrenie 2019. Available online: https://www.awmf.org/leitlinien/detail/ll/038-009.html
Galletly C, Castle D, Dark F et al (2016) Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for the management of schizophrenia and related disorders. Aust N Z J Psychiatry 50:410–472
Hasan A, Falkai P, Wobrock T et al (2015) World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of schizophrenia. Part 3: update 2015 management of special circumstances: depression, suicidality, substance use disorders and pregnancy and lactation. World J Biol Psychiatry 16:142–170
Colizzi M, Murray R (2018) Cannabis and psychosis: what do we know and what should we do? Br J Psychiatry 212:195–196
Ruther T, Bobes J, De Hert M et al (2014) EPA guidance on tobacco dependence and strategies for smoking cessation in people with mental illness. Eur Psychiatry 29:65–82
Nielsen SM, Toftdahl NG, Nordentoft M et al (2017) Association between alcohol, cannabis, and other illicit substance abuse and risk of developing schizophrenia: a nationwide population based register study. Psychol Med 47:1668–1677
Hjorthoj C, Albert N, Nordentoft M (2018) Association of substance use disorders with conversion from schizotypal disorder to schizophrenia. JAMA Psychiatry 75:733–739
Pasman JA, Verweij KJH, Gerring Z, Stringer S, Sanchez-Roige S, Treur JL, Abdellaoui A, Nivard MG, Baselmans BML, Ong J-S, Ip HF, van der Zee MD, Bartels M, Day FR, Fontanillas P, Elson SL, de Wit H, Davis LK, MacKillop J, Derringer JL, Branje SJT, Hartman CA, Heath AC, van Lier PAC, Madden PAF, Maegi R, Meeus W, Montgomery GW, Oldehinkel AJ, Pausova Z, Ramos-Quiroga JA, Paus T, Ribases M, Kaprio J, Boks MPM, Bell JT, Spector TD, Gelernter J, Boomsma DI, Martin NG, MacGregor S, Perry JRB, Palmer AA, Posthuma D, Munafo MR, Gillespie NA, Derks EM, Vink JM (2018) GWAS of lifetime cannabis use reveals new risk loci, genetic overlap with psychiatric traits, and a causal effect of schizophrenia liability. Nature Neuroscience 21(9):1161–1170
Acknowledgements
We acknowledge the contribution of Johannes Kabisch, Kathrin Schacherbauer, Luise Jacob, Sophia Schmieder, Udo Bonnet, Jan Copeland, Marica Ferri, Christopher Fowler, Winfried Häuser, Derik Hermann, Burkhard Hinz, Michael Höfler, Joseph Kambeitz, Ludwig Kraus, Beat Lutz, Frank Petzke, Liane Paul, Lukas Radbruch, Martin Storr, Michael Schäfer.
Funding
This paper was prepared in the context of the study “Cannabis: Potential and risks. A scientific analysis” (PIs: Dr. Eva Hoch, Dr. Miriam Schneider) funded by the German Ministry of Health. The funding sources had no influence on the design of the study or the analysis and interpretation of the results.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
AH was an advisory board member of Janssen-Cliag, Otsuka, Lundbeck and Roche and he was a speaker for Janssen-Cliag, Otsuka and Lundbeck. FML is a shareholder of curantis UG (ltd.) and has received research grants from the German Federal Ministry of Education and Research and Acerus Pharmaceuticals. EH received research grants from the German Federal Ministry of Health and the European Monitoring Centre for Drugs and Drug Addiction. She receives fees for trainings and a treatment manual for cannabis use disorders. WS received speakers fees by Mag & More. All other authors did not report a conflict of interest. All other authors did not report any conflicts of interest related to the content of this article.
Electronic supplementary material
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Hasan, A., von Keller, R., Friemel, C.M. et al. Cannabis use and psychosis: a review of reviews. Eur Arch Psychiatry Clin Neurosci 270, 403–412 (2020). https://doi.org/10.1007/s00406-019-01068-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00406-019-01068-z