The DOI matches its Crossref record; 6 of the 6 references it cites were found in a registry or an index.
Cannabis Use and Earlier Onset of Psychosis: A Systematic Meta-analysis
Abstract
CONTEXT: A number of studies have found that the use of cannabis and other psychoactive substances is associated with an earlier onset of psychotic illness. OBJECTIVE: To establish the extent to which use of cannabis, alcohol, and other psychoactive substances affects the age at onset of psychosis by meta-analysis. DATA SOURCES: Peer-reviewed publications in English reporting age at onset of psychotic illness in substance-using and non-substance-using groups were located using searches of CINAHL, EMBASE, MEDLINE, PsycINFO, and ISI Web of Science. STUDY SELECTION: Studies in English comparing the age at onset of psychosis in cohorts of patients who use substances with age at onset of psychosis in non-substance-using patients. The searches yielded 443 articles, from which 83 studies met the inclusion criteria. DATA EXTRACTION: Information on study design, study population, and effect size were extracted independently by 2 of us. DATA SYNTHESIS: Meta-analysis found that the age at onset of psychosis for cannabis users was 2.70 years younger (standardized mean difference = -0.414) than for nonusers; for those with broadly defined substance use, the age at onset of psychosis was 2.00 years younger (standardized mean difference = -0.315) than for nonusers. Alcohol use was not associated with a significantly earlier age at onset of psychosis. Differences in the proportion of cannabis users in the substance-using group made a significant contribution to the heterogeneity in the effect sizes between studies, confirming an association between cannabis use and earlier mean age at onset of psychotic illness. CONCLUSIONS: The results of meta-analysis provide evidence for a relationship between cannabis use and earlier onset of psychotic illness, and they support the hypothesis that cannabis use plays a causal role in the development of psychosis in some patients. The results suggest the need for renewed warnings about the potentially harmful effects of cannabis.
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Cites
Meta-analysis of Observational Studies in Epidemiology<SUBTITLE>A Proposal for Reporting</SUBTITLE>
Stroup, D. F. (2000) · JAMA · doi:10.1001/jama.283.15.2008 · Cited by 20,623
Duval, S., & Tweedie, R. (2000) · Biometrics · doi:10.1111/j.0006-341x.2000.00455.x · Cited by 14,099
Meta-analysis of individual participant data: rationale, conduct, and reporting
Riley, R. D., Lambert, P. C., & Abo-Zaid, G. (2010) · BMJ · doi:10.1136/bmj.c221 · Cited by 1,701
Degenhardt, L., Chiu, W.-T., Sampson, N., Kessler, R. C., Anthony, J. C., Angermeyer, M., Bruffaerts, R., de Girolamo, G., Gureje, O., Huang, Y., et al. (2008) · PLoS Medicine · doi:10.1371/journal.pmed.0050141 · Cited by 796
Substance abuse in schizophrenia: a review of the literature and a study of correlates in Sweden
Cantor-Graae, E., Nordström, L. G., & McNeil, T. F. (2001) · Schizophrenia Research · doi:10.1016/s0920-9964(00)00114-6 · Cited by 261 · cited 1×
“A third area of methodological variation is whether the studies examined substance use at the time of initial presentation to mental health services(33,34) or later in the course of established psychotic illness.(35,36) A fourth difference is in the nature of the control group, because some studies use psychotic patie…”
ResultCannabis and the developing brain: Insights from behavior
Trezza, V., Cuomo, V., & Vanderschuren, L. J. M. J. (2008) · European Journal of Pharmacology · doi:10.1016/j.ejphar.2008.01.058 · Cited by 131
Cited by
Meta-analysis of the Association Between the Level of Cannabis Use and Risk of Psychosis
Marconi, A., Di Forti, M., Lewis, C. M., Murray, R. M., & Vassos, E. (2016) · Schizophrenia Bulletin · doi:10.1093/schbul/sbw003 · Cited by 899
Galletly, C., Castle, D., Dark, F., Humberstone, V., Jablensky, A., Killackey, E., Kulkarni, J., McGorry, P., Nielssen, O., & Tran, N. (2016) · Australian & New Zealand Journal of Psychiatry · doi:10.1177/0004867416641195 · Cited by 877
Self-citationEffects of Cannabis Use on Human Behavior, Including Cognition, Motivation, and Psychosis: A Review
Volkow, N. D., Swanson, J. M., Evins, A. E., DeLisi, L. E., Meier, M. H., Gonzalez, R., Bloomfield, M. A. P., Curran, H. V., & Baler, R. (2016) · JAMA Psychiatry · doi:10.1001/jamapsychiatry.2015.3278 · Cited by 867
The increasing global health priority of substance use in young people
Degenhardt, L., Stockings, E., Patton, G., Hall, W. D., & Lynskey, M. (2016) · The Lancet Psychiatry · doi:10.1016/s2215-0366(15)00508-8 · Cited by 601
de Girolamo, G., Dagani, J., Purcell, R., Cocchi, A., & McGorry, P. D. (2012) · Epidemiology and Psychiatric Sciences · doi:10.1017/s2045796011000746 · Cited by 544
Metadata
- Authors
- Large, M., Sharma, S., Compton, M. T., Slade, T., & Nielssen, O.
- Venue
- Archives of General Psychiatry
- Publisher
- American Medical Association (AMA)
- Published
- 2011-06-06
- Volume
- 68
- Issue
- 6
- Pages
- 555
- ISSN
- 0003-990X (ISSN-L)
- OpenAlex
- W2016732910
- Cited by
- 563
- References
- 6
- FWCI
- 32.96
- Type
- journal article
- Language
- en
- Open access
- closed
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