The Cannabis Pathway to Non-Affective Psychosis may Reflect Less Neurobiological Vulnerability.
Else-Marie Løberg, Siri Helle, Merethe Nygård, Jan Øystein Berle, Rune A Kroken, Erik Johnsen
Frontiers in Psychiatry 2014 DOI: 10.3389/fpsyt.2014.00159 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Longitudinal Peer reviewed |
|---|---|
| Population | Patients with non-affective psychosis |
| Topics | Cannabis |
| Keywords | Age of onset Cognition Psychosis Schizophrenia |
| Key findings | Cannabis-using patients with non-affective psychosis show fewer cognitive deficits and neurological soft signs than non-using patients, suggesting less neurobiological vulnerability, but also have familial and genetic vulnerabilities that may increase sensitivity to cannabis. |
Abstract
There is a high prevalence of cannabis use reported in non-affective psychosis. Early prospective longitudinal studies conclude that cannabis use is a risk factor for psychosis, and neurochemical studies on cannabis have suggested potential mechanisms for this effect. Recent advances in the field of neuroscience and genetics may have important implications for our understanding of this relationship. Importantly, we need to better understand the vulnerability × cannabis interaction to shed light on the mediators of cannabis as a risk factor for psychosis. Thus, the present study reviews recent literature on several variables relevant for understanding the relationship between cannabis and psychosis, including age of onset, cognition, brain functioning, family history, genetics, and neurological soft signs (NSS) in non-affective psychosis. Compared with non-using non-affective psychosis, the present review shows that there seem to be fewer stable cognitive deficits in patients with cannabis use and psychosis, in addition to fewer NSS and possibly more normalized brain functioning, indicating less neurobiological vulnerability for psychosis. There are, however, some familiar and genetic vulnerabilities present in the cannabis psychosis group, which may influence the cannabis pathway to psychosis by increasing sensitivity to cannabis. Furthermore, an earlier age of onset suggests a different pathway to psychosis in the cannabis-using patients. Two alternative vulnerability models are presented to integrate these seemingly paradoxical findings.
Comparable studies
Other narrative reviews on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Causal association between cannabis and psychosis: examination of the evidence | 2004 | Review | |
| Cannabis sativa: A comprehensive ethnopharmacological review of a medicinal plant with a long history. General (historical and pharmacological review) | 2018 | Review | |
| Psychiatric effects of cannabis | 2001 | Review | |
| Beyond THC: The New Generation of Cannabinoid Designer Drugs | 2011 | Review | |
| Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug | 2006 | Review |
Citations in the library
Cited by 8
- Traditional marijuana, high‐potency cannabis and synthetic cannabinoids: increasing risk for psychosis World Psychiatry September 22, 2016
- Neurological soft signs in Tunisian patients with first-episode psychosis and relation with cannabis use Annals of General Psychiatry July 12, 2017
- Eye movements in patients in early psychosis with and without a history of cannabis use Schizophrenia May 12, 2021
- Timing of Cannabis Exposure Relative to Prodrome and Psychosis Onset in a Community-Based First Episode Psychosis Sample Journal of Psychiatric Research 2022
- Geographical variation in hospitalization for psychosis associated with cannabis use and cannabis legalization in the United States Psychiatry Research 2022
and 3 more in the library
Cites 32
- A default mode of brain function Proceedings of the National Academy of Sciences January 16, 2001
- Causal association between cannabis and psychosis: examination of the evidence The British Journal of Psychiatry January 30, 2004
- Gone to Pot – A Review of the Association between Cannabis and Psychosis Frontiers in Psychiatry May 22, 2014
- Effects of cannabis use on outcomes of psychotic disorders: systematic review The British Journal of Psychiatry October 31, 2008
- 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 Schizophrenia Bulletin July 25, 2010
and 27 more in the library