Cannabis use and the risk of later schizophrenia: a review
Version of Record online: 25 MAR 2004
Volume 99, Issue 4, pages 425–430, April 2004
How to Cite
Smit, F., Bolier, L. and Cuijpers, P. (2004), Cannabis use and the risk of later schizophrenia: a review. Addiction, 99: 425–430. doi: 10.1111/j.1360-0443.2004.00683.x
- Issue online: 25 MAR 2004
- Version of Record online: 25 MAR 2004
- Submitted 14 July 2003; initial review completed 2 October 2003; final version accepted 5 December 2003
- public mental health;
Aim To study the role of cannabis use in the onset of symptoms and disorders in the schizophrenia spectrum.
Design Review of five population-based, longitudinal studies on the relationship between cannabis use and problems ranging from the experience of psychotic symptoms to hospitalization with a confirmed diagnosis of schizophrenia. Several hypotheses are examined that may explain this relationship: (1) self-medication; (2) effects of other drugs; (3) confounding; (4) stronger effect in predisposed people, and (5) etiological hypothesis.
Findings Hypotheses 1 and 2 can be dismissed; hypothesis 3 is still open to debate, and converging evidence is found for hypotheses 4 and 5—antecedent cannabis use appears to act as a risk factor in the onset of schizophrenia, especially in vulnerable people, but also in people without prior history.
Conclusion There is an intrinsic message here for public health, but how that message is to be translated into action is not immediately clear.