HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS British Journal of Psychiatry Psychiatric Bulletin All RCPsych Journals		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Related articles in APT Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Macleod, J. Search for Related Content PubMed Articles by Macleod, J.

Cannabis use and psychosis: the origins and implications of an association

John Macleod’s clinical interest in problem drug use dates from his work in Edinburgh in the 1990s as a general practitioner and as medical officer for a street sex-workers’ outreach project. Supported by the Wellcome Trust, he trained in epidemiology at the London School of Hygiene and Tropical Medicine, after which he worked as a GP in Birmingham, where he undertook epidemiological research at the University. He is now Reader in Clinical Epidemiology and Primary Care at the University of Bristol (Department of Social Medicine, University of Bristol, Canynge Hall, Whiteladies Road, Bristol BS8 2PR, UK. Email: john.macleod{at}bristol.ac.uk). He is involved in ongoing studies of the causes and consequences of drug use based in Edinburgh and Bristol.

Evidence for the effectiveness of treatment or secondary prevention of psychotic illness such as schizophrenia is often disappointing. This situation reflects our limited understanding of the aetiology of psychosis. There is good evidence that both genetic and environmental factors are implicated but the precise identity of these is unclear. Cannabis use is one candidate as a possible, modifiable environmental influence on both incidence and prognosis of psychosis. Evidence supporting this candidature is exclusively observational, and its strength has perhaps been overestimated and problems related to its interpretation underestimated by some. Nevertheless the possibility that cannabis does cause psychosis remains. Because of this, and because there are other good public health reasons to prevent cannabis use, interventions targeting use need to be evaluated. This evaluation, along with other imaginative approaches to future research, is needed to further our understanding of the determinants of mental illness and how we can most effectively improve the population’s mental health.

Related articles in APT:

Epidemiology: what it is and why it matters: INVITED COMMENTARY ON ... CANNABIS USE AND PSYCHOSIS

Brendan D. Kelly
APT 2007 13: 412-413. [Abstract] [Full Text]  

This article has been cited by other articles:

				B. D. Kelly Epidemiology: what it is and why it matters: INVITED COMMENTARY ON ... CANNABIS USE AND PSYCHOSIS Advan. Psychiatr. Treat., November 1, 2007; 13(6): 412 - 413. [Abstract] [Full Text] [PDF]