“At the 2022 International Congress of the Royal College of Psychiatrists, Danish researcher Carsten Hjorthøj, (an associate professor at the University of Copenhagen and research leader at Copenhagen Research Center for Mental Health), presented the following data. The International Congress is the annual conference of the Royal College of Psychiatrists, which oversees the practice of psychiatry in Great Britain suggested that cannabis might be responsible for 25 percent of new cases of schizophrenia in young men.

This figure is far higher than previous estimates, which generally ranged from 5 to 10 percent. It would translate into tens of thousands of additional cases of new-onset schizophrenia annually in the United States and Europe.

To put a 25 percent figure in context, genetic factors are generally said to account for about half of the risk of schizophrenia. This estimate would imply that cannabis use now carries roughly half as much as risk overall as a genetic predisposition to the illness.

Schizophrenia is among the most serious mental illnesses, causing lifelong unemployment and disability in many patients and reducing their life expectancy by about 15 years on average. Untreated schizophrenia is also a high risk factor for extreme violence.” (Source: Cannabis may now cause one in four new cases of schizophrenia in men (substack.com))

Hospitalization for psychosis associated with cannabis use and cannabis legalization in the United States Submit to: Psychiatry Research

  • Hospitalizations for psychosis/cannabis use more likely in areas where cannabis legalized.
  • Recreational cannabis legalization associated with greater rate of hospitalization for psychosis associated with cannabis use.
  • Findings warrant future longitudinal studies to evaluate psychosis in U.S. states

Abstract: The 2017 National Inpatient Sample database was utilized to investigate the association between cannabis legalization in the United States and hospitalizations for psychosis associated with cannabis use. We compared the odds of hospital discharges for psychosis associated with cannabis use in adults between the Pacific census division (where most states legalized recreational cannabis use) and other divisions using multivariable logistic regression, adjusting for confounders…There was a significant correlation between the cannabis legality score and proportion of hospital discharges for psychosis associated with cannabis use (r = 0.67, p<0.05). In conclusion, we observed a higher proportion of hospital discharges for psychosis associated with cannabis use in areas with more liberal cannabis legalization laws. (For complete research https://www.sciencedirect.com/science/article/abs/pii/S0165178122000014 )


When Cannabis Use Goes Wrong: Mental Health Side Effects of Cannabis Use That Present to Emergency Services – Canada

Cannabis use is a modifiable risk factor for the development and exacerbation of mental illness. The strongest evidence of risk is for the development of a psychotic disorder, associated with early and consistent use in youth and young adults. Cannabis-related mental health adverse events precipitating Emergency Department (ED) or Emergency Medical Services presentations can include anxiety, suicidal thoughts, psychotic or attenuated psychotic symptoms, and can account for 25–30% of cannabis-related ED visits. Up to 50% of patients with cannabis-related psychotic symptoms presenting to the ED requiring hospitalization will go on to develop schizophrenia.

With the legalization of cannabis in various jurisdiction and the subsequent emerging focus of research in this area, our understanding of who (e.g., age groups and risk factors) are presenting with cannabis-related adverse mental health events in an emergency situation is starting to become clearer. However, for years we have heard in popular culture that cannabis use is less harmful or no more harmful than alcohol use; however, this does not appear to be the case for everyone. It is evident that these ED presentations should be considered another aspect of potentially harmful outcomes that need to be included in knowledge mobilization. In the absence of a clear understanding of the risk factors for mental health adverse events with cannabis use it can be instructive to examine what characteristics are seen with new presentations of mental illness both in emergency departments (ED) and early intervention services for mental illness. In this narrative review, we will discuss what is currently known about cannabis-related mental illness presentations to the ED, discussing risk variables and outcomes both prior to and after legalization, including our experiences following cannabis legalization in Canada. We will also discuss what is known about cannabis-related ED adverse events based on gender or biological sex. We also touch on the differences in magnitude between the impact of alcohol and cannabis on emergency mental health services to fairly present the differences in service demand with the understanding that these two recreational substances may impact different populations of individuals at risk for adverse events.

The demands of cannabis users on emergency services both ED and EHS are one of the more unmet needs of research on how cannabis impacts healthcare systems and are of pressing importance as more jurisdictions move toward legalization. (For complete Research https://www.frontiersin.org/articles/10.3389/fpsyt.2021.640222/full )

Full Research Hospitalization_for_psychosis_associated_with_cannabis_use_and_cannabis_legalization_in_the_US.pdf

Dalgarno Institute Research & Communication Team