Cannabis and Psychosis: A Review of the Risk Factors Involved
Mohamed Ben Amar
American Journal of Plant Sciences 2020 DOI: 10.4236/ajps.2020.1112139 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Systematic review Longitudinal Qualitative Peer reviewed |
|---|---|
| Topics | Cannabis |
| Keywords | Psychosis |
| Citations | 3 |
| Key findings | Six risk factors—dose-response, early age of use, genetic susceptibility, childhood trauma, cigarette smoking, and urban environment—are associated with cannabis-related psychosis, while CBD is associated with fewer psychotic symptoms. |
Abstract
Abundant literature suggests the hypothesis that cannabis use leads to the onset of psychotic symptoms. However, the nature of the association and the causal link remain controversial. This review aims to identify the risk factors involved in the etiopathogenesis of psychosis or psychotic features. Our electronic search found 1653 studies published until March 1st 2020. Longitudinal studies and literature reviews were selected if they addressed specifically the issues of the cannabis/psychosis relationship and the eventual risk factors involved. Our systematic review identified six potential risk factors involved in the association. They are, in decreasing importance, the dose-response relationship (quantity, frequency and duration of cannabis use), the early age of cannabis consumption, genetic susceptibility, childhood trauma, cigarette smoking and urban environment. In contrast, a significant inverse relationship exists between cannabidiol (CBD) and psychosis: cannabidiol is associated with less psychotic symptoms and manifests antipsychotic properties. Further studies are needed to establish a clear causal relationship between cannabis and psychosis and to identify the qualitative and quantitative contribution of specific risk factors on its onset and sustainability.
Comparable studies
Other systematic reviews and meta-analyses on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Effects of cannabis use on outcomes of psychotic disorders: systematic review People with psychotic disorders, as examined in 13 longitudinal studies | 2008 | Systematic review | |
| The Impact of Cannabis Use on Cognitive Functioning in Patients With Schizophrenia: A Meta-analysis of Existing Findings and New Data in a First-Episode Sample Patients with established schizophrenia (meta-analysis: 572) and patients with... | 2010 | Meta-analysis and cross-sectional observational study | n = 700 |
| Medicinal cannabis for psychiatric disorders: a clinically-focused systematic review | 2020 | Systematic review | |
| Neuroimaging in cannabis use: a systematic review of the literature Cannabis users and controls in neuroimaging studies | 2009 | Systematic review | |
| Human Laboratory Studies on Cannabinoids and Psychosis. Healthy human subjects and individuals with schizophrenia | 2016 | Systematic review |
Citations in the library
Cites 45
- Psychosis as a state of aberrant salience: a framework linking biology, phenomenology, and pharmacology in schizophrenia. American Journal of Psychiatry 2003
- Causal association between cannabis and psychosis: examination of the evidence The British Journal of Psychiatry January 30, 2004
- High-potency cannabis and the risk of psychosis The British Journal of Psychiatry November 30, 2009
- Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug Brazilian Journal of Medical and Biological Research April 1, 2006
- Traditional marijuana, high‐potency cannabis and synthetic cannabinoids: increasing risk for psychosis World Psychiatry September 22, 2016
and 40 more in the library