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Cited by 257Schizophrenia research and treatmentCannabis and Cannabinoid ResearchPsychopathy, Forensic Psychiatry, Sexual Offending

Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: Follow-up study of 535 incident cases

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Arendt, Mikkel, Rosenberg, Raben, Foldager, Leslie, Perto, Gurli, Munk-Jørgensen, Povl·2005·British Journal of Psychiatry
DOI 10.1192/bjp.187.6.510
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Abstract

BACKGROUND: Few studies have examined samples of people with cannabis-induced psychotic symptoms. AIMS: To establish whether cannabis-induced psychotic disorders are followed by development of persistent psychotic conditions, and the timing of their onset. METHOD: Data on patients treated for cannabis-induced psychotic symptoms between 1994 and 1999 were extracted from the Danish Psychiatric Central Register. Those previously treated for any psychotic symptoms were excluded. The remaining 535 patients were followed for at least 3 years. In a separate analysis, the sample was compared with people referred for schizophrenia-spectrum disorders for the first time, but who had no history of cannabis-induced psychosis. RESULTS: Schizophrenia-spectrum disorders were diagnosed in 44.5% of the sample. New psychotic episodes of any type were diagnosed in 77.2%. Male gender and young age were associated with increased risk. Development of schizophrenia-spectrum disorders was often delayed, and 47.1% of patients received a diagnosis more than a year after seeking treatment for a cannabis-induced psychosis. The patients developed schizophrenia at an earlier age than people in the comparison group (males, 24.6 v. 30.7 years, females, 28.9 v. 33.1 years). CONCLUSIONS: Cannabis-induced psychotic disorders are of great clinical and prognostic importance.

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  • There is no robust evidence of clinical characteristics that allow the distinction of cannabis-induced psychotic disorder to be made.

    “Nor do we review case-studies or studies relying on a diagnosis of cannabis-induced psychotic disorder, as such diagnoses are dependent on assumptions of a causal role of cannabis in specific cases by a clinician, and there is no robust evidence as far as we are aware of clinical characteristics that allow the distinction of this disorder to be made (3).”

    From Association Between Cannabis and Psychosis: Epidemiologic Evidence (2016) · cites this paper as [3]

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Authors
Arendt, M., Rosenberg, R., Foldager, L., Perto, G., & Munk-Jørgensen, P.
Affiliations
Aarhus University Hospital (DK)
Corresponding author
Arendt, Mikkel
ORCID
Foldager, Leslie
Venue
British Journal of Psychiatry
Publisher
Royal College of Psychiatrists
Published
2005-12
Volume
187
Issue
6
Pages
510-515
ISSN
  • 0007-1250 (ISSN-L)
  • 1472-1465
DOI
10.1192/bjp.187.6.510
OpenAlex
W2155659950
Cited by
257
References
35
Citations by year
2026: 10 · 2025: 8 · 2024: 10 · 2023: 11 · 2022: 12 · 2021: 6 · 2020: 10 · 2019: 9 · 2018: 12 · 2017: 14 · 2016: 13 · 2015: 13 · 2014: 11 · 2013: 13 · 2012: 18
FWCI
7.22
Type
journal article
Language
en
Open access
Licence
www.cambridge.org/core/terms (unspecified, 4415 d)
Locations
  • The British Journal of Psychiatry (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Schizophrenia research and treatment
  • Health Sciences › Medicine › Pharmacology › Cannabis and Cannabinoid Research
  • Social Sciences › Psychology › Clinical Psychology › Psychopathy, Forensic Psychiatry, Sexual Offending
Keywords
cannabis-induced psychosis, schizophrenia spectrum disorders, cannabis use, age of onset, gender differences, risk factors, prognosis
MeSH terms
Adult, Age Factors, Cannabis, Marijuana Abuse, Denmark, Female, Follow-Up Studies, Humans, Male, Psychotic Disorders, Recurrence, Risk Factors, Schizophrenia, Sex Factors, Incidence, Age of Onset

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