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Cited by 70Cannabis and Cannabinoid ResearchSchizophrenia research and treatmentMental Health Treatment and Access

Assessing the impact of cannabis use on trends in diagnosed schizophrenia in the United Kingdom from 1996 to 2005

Frisher, Martin, Crome, Ilana, Martino, Orsolina, Croft, Peter·2009·Schizophrenia Research
DOI 10.1016/j.schres.2009.05.031
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Abstract

A recent systematic review concluded that cannabis use increases risk of psychotic outcomes independently of confounding and transient intoxication effects. Furthermore, a model of the association between cannabis use and schizophrenia indicated that the incidence and prevalence of schizophrenia would increase from 1990 onwards. The model is based on three factors: a) increased relative risk of psychotic outcomes for frequent cannabis users compared to those who have never used cannabis between 1.8 and 3.1, b) a substantial rise in UK cannabis use from the mid-1970s and c) elevated risk of 20 years from first use of cannabis. This paper investigates whether this has occurred in the UK by examining trends in the annual prevalence and incidence of schizophrenia and psychoses, as measured by diagnosed cases from 1996 to 2005. Retrospective analysis of the General Practice Research Database (GPRD) was conducted for 183 practices in England, Wales, Scotland and Northern Ireland. The study cohort comprised almost 600,000 patients each year, representing approximately 2.3% of the UK population aged 16 to 44. Between 1996 and 2005 the incidence and prevalence of schizophrenia and psychoses were either stable or declining. Explanations other than a genuine stability or decline were considered, but appeared less plausible. In conclusion, this study did not find any evidence of increasing schizophrenia or psychoses in the general population from 1996 to 2005.

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Crossref · 10.1016/j.schres.2009.05.031

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  • Some studies have found that incidence of psychotic outcomes has increased in recent decades, while others have found no change, or a decrease.

    “Some studies have found that incidence of psychotic outcomes has increased in recent decades (58,59), while others have found no change, or a decrease (60,61).”

    From Association Between Cannabis and Psychosis: Epidemiologic Evidence (2016) · cites this paper as [61]

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Authors
Frisher, M., Crome, I., Martino, O., & Croft, P.
Affiliations
  • Keele University (GB)
  • Harplands Hospital (GB)
Corresponding author
Frisher, Martin
ORCID
Venue
Schizophrenia Research
Publisher
Elsevier BV
Published
2009-09
Volume
113
Issue
2-3
Pages
123-128
ISSN
0920-9964 (ISSN-L)
DOI
10.1016/j.schres.2009.05.031
OpenAlex
W2111803651
Cited by
70
References
26
Citations by year
2023: 16 · 2022: 2 · 2021: 3 · 2020: 3 · 2019: 1 · 2018: 4 · 2017: 1 · 2016: 2 · 2015: 7 · 2014: 3 · 2013: 8 · 2012: 4
FWCI
4.55
Type
journal article
Language
en
Open access
closed
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Schizophrenia Research (publishedVersion)
  • PubMed (publishedVersion)
Funders
Medical Research Council
Topics
  • Health Sciences › Medicine › Pharmacology › Cannabis and Cannabinoid Research
  • Health Sciences › Medicine › Psychiatry and Mental health › Schizophrenia research and treatment
  • Social Sciences › Psychology › Social Psychology › Mental Health Treatment and Access
Keywords
cannabis use, schizophrenia
MeSH terms
Adolescent, Adult, Marijuana Abuse, Female, United Kingdom, Humans, Male, Psychotic Disorders, Retrospective Studies, Risk Factors, Schizophrenia, Incidence, Prevalence, Age of Onset, Young Adult

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