According to a new study from Europe, people who use marijuana daily may be exposed to the higher risk of developing psychosis, especially if they use high-potency marijuana.
The study was conducted on nearly 1,200 people without psychosis and living in 10 European cities and 1 city in Brazil. They are compared with 900 people living in the same cities and were diagnosed with psychosis for the first time.
The scientists concluded that people who reported using marijuana on a daily basis have three-times more risk of developing first-episode psychosis compared to people who did not use the drug ever. Moreover, people reported using high-potency marijuana everyday were having five times more risk of developing first-episode psychosis, compared to people who never had it.
It is the first study revealing the effect of a typical pattern of marijuana use in a given area, which may contribute to the level of psychosis in the population in that area. For instance, in Amsterdam, where there is high availability of high-potency cannabis, there were people who reported the use of high-potency cannabis daily were nine times more prone to develop psychosis as compared to people who did not use marijuana.
Lead author Dr. Marta Di Forti of King’s College London, said, “As the legal status of cannabis changes in many countries and states, and as we consider the medicinal properties of some types of cannabis, it is of vital public health importance that we also consider the potential adverse effects that are associated with daily cannabis use, especially high-potency varieties.”
Yet, the study merely found the link between the said drug and psychosis, and cannot prove that using marijuana leads to psychosis.
The study was published on March 19 in the medical journal The Lancet Psychiatry.
In some of the previous studies, it was found that there is an association between heavy marijuana use and psychosis. However, these studies failed to determine how this link can be associated with the degree of psychosis in the common population.
As per the new study, the investigators analyzed that around 30 percent of patients with psychosis used marijuana on a daily basis compared with just 7 percent of people without psychosis, and roughly 37 percent of people reported the use of high-potency marijuana compared with 19 percent of people without psychosis. In addition to that, the study also found that the amount of cannabis use among the controls in a specified location was associated with the development rate of psychosis in that location. So the higher rate of psychosis can be the result of daily use of the drug by more people and the number of people using high-potency marijuana.
