Cannabis and schizophrenia: characterisation of a risk factor in a sample of Moroccan patients hospitalised for psychosis
El Hassan Ouanouche, Hicham Elmostafi, Naoufal Amarat, O. Wafaa, Tamouza Ryad, A. El Hessni, A. Mesfioui
Middle East Current Psychiatry February 10, 2022 DOI: 10.1186/s43045-022-00173-5 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Prospective descriptive study Peer reviewed |
|---|---|
| Sample size | 95 |
| Population | Patients diagnosed with schizophrenia according to DSM-5 criteria in the psychiatric department of Moulay ben Abdallah Hospital in Essaouira, Morocco |
| Measures | Positive and Negative Syndrome Scale, Clinician-Rated Dimensions of Psychosis Symptom Severity, Cannabis Abuse Screening Test |
| Topics | Cannabis |
| Key points | Cannabis users with schizophrenia were younger, exclusively male, and of lower educational and economic status than non-users. The authors report a dose effect of cannabis on positive and negative symptoms and a significant predictive link for age of onset of cannabis use, concluding that problematic cannabis use can be considered a risk factor for the emergence and worsening of schizophrenic disorder. |
Abstract
In addition to the biological plausibility widely described through a very large number of studies, the causal link between cannabis uses and schizophrenia disorders has become illicit internationally and given the scarcity of similar studies in Morocco. Our study consists of a prospective descriptive study in the psychiatric department of the Moulay ben Abdallah Hospital in Essaouira. The sample consisted of 95 patients diagnosed with schizophrenia according to the DSM5 criteria. The diagnostic assessment included the Positive and Negative Syndrome Scale to assess the severity of positive and negative symptoms of schizophrenia as well as the patient’s general psychopathology, the Clinician-Rated Dimensions of Psychosis Symptom Severity to assess the symptom severity of the psychotic dimensions according, and the Cannabis Abuse Screening Test to assess the extent of cannabis use. The mean age of the patients recruited in the study was 33.7 ± 9.37 years with a clear male predominance (p < 0.0001). Cannabis users compared to non-users were younger and comprised only men. Cannabis users also have a lower educational and economic level than non-users. Furthermore, a clear dose effect of cannabis uses on the onset of positive and negative symptoms of schizophrenia. The temporality criterion is clear in our study, since the predictivity of the parameter: “age of onset of cannabis use” is highly significant (p = 0.000). These results suggest that cannabis use can be considered as the most illicit risk factor for the development and/or onset of schizophrenia. These results suggest that there is a causal relationship between cannabis use and/or dependence (problematic use) and the onset and/or worsening of schizophrenic disorder. This means that problematic cannabis use can be considered as a real risk factor for the emergence and development of schizophrenic disorder.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |
Citations in the library
Cites 5
- Traditional marijuana, high‐potency cannabis and synthetic cannabinoids: increasing risk for psychosis World Psychiatry September 22, 2016
- Cannabis use and vulnerability for psychosis in early adolescence—a TRAILS study Addiction December 10, 2012
- [Cannabis: Similarities and differences with tobacco]. Revue des maladies respiratoires June 1, 2020
- Cannabis consumption and psychosis or schizophrenia development International Journal of Social Psychiatry November 1, 2018
- The psychotomimetic effects of intravenous delta-9-tetrahydrocannabinol in healthy individuals: implications for psychosis. Neuropsychopharmacology August 2004