A recent cannabis study on multiple patients claims that high potency cannabis with varieties combined with frequent use tend to increase chances of mental health problems among users.
Experts have previously flagged the link between cannabis and psychosis, especially among vulnerable people who consumed cannabis in high dosage. Moreover, recent studies suggest that potency of the cannabis consumed has a vital role to play in how many new cases of psychotic disorders arise in the city.
Prohibiting the use of high-potency cannabis would result in lower mental disorder as per the study which estimated that 30% of first-time of psychotic disorders in south London, and half of those in Amsterdam, were all results of high-potency cannabis consumption. The team says that this equates to almost 60 fewer cases per year in south London.
â€śIf you are a psychologist like me who works in this catchment area and sees first-episode psychosis patients, this has a significant impact at the level of services and, I would also argue, family and society,â€ť said Dr Marta Di Forti, the lead author of the research, from Kingâ€™s College London.
High-strength cannabis contains high levels of Tetrahydro cannabinoid, popularly known as THC which is responsible for the â€śhighâ€ť that one might feel after inhaling cannabis. It is a psychotic component found in the cannabis plant which can cause mental disorders and create an imbalance of chemicals in the body leading to several diseases.
Skunk, a high-strength cannabis has levels of THC above 10%. According to the data released last year, 94% police cannabis seizures in the UK were of high strength varieties, entailing minute traces of cannabinoid aka CBD which is a non-psychoactive component that could possibly reduce the high or prevent it altogether.
Writing in the journal Lancet Psychiatry, Di Forti and an international team of researchers report how they studied patient data â€“ including cannabis use- recorded between mid-2010 and mid-2015 about 901 adults under the age of 65 who visited mental health services in one of the 10 locations in Europe, or one in Brazil, and received their first diagnosis of a psychotic disorder which did not result into, for example, brain tumours or acute drug use.
After considering an array of conditions including drinking habits, smoking cigarettes, educational background and use of other drugs like ketamine, the team discovered that patients with psychotic disorders were more likely to have consumed cannabis at some point of time in their lives as compared to those who were healthy.
The team also concluded that the chances of having a psychotic disorder were higher by 40% in those who used cannabis frequently â€“ more than once a week â€“ as compared to those who did it rarely or occasionally. Moreover, the chances of having a psychotic disorder were thrice in people who consumed cannabis on a daily basis as compared to those who rarely took it.
The most severe case of mental disorders is linked to people who consumed cannabis at a high frequency combined with high potency as compared to those who never did it or rarely did.
Daily cannabis use linked with psychotic disorders in people can be observed in Amsterdam, where the chances were seven times higher than for people who never used cannabis. Almost all the cannabis sold in coffee shops in Amsterdam are of high potency. On the other hand, varieties of cannabis with 67% THC can be found in Netherlands.
Registered cases of psychotic disorders were found highest in Amsterdam that other locations studied, with only south London surpassing it.
â€śDaily use of high-potency cannabis and how this varies across Europe explains some of the striking variations we have measured in the incidence of psychotic disorder,â€ť said Di Forti.
However, she duly noted that not every person who consumes cannabis on a daily basis is bound to suffer from a psychotic disorder, she said that there are multiple reasons and factors contributing to these mental disorders, cannabis alone, cannot be taken as the only reason causing psychosis.
The study had its own limitations owing to the fact that it was self-reported use of cannabis and a small number of participants were involved. Also, THC and CBD were not measured in exact proportions, however, cannabis with high potency combined with increased frequency was a common factor noted in majority of the cases.