A new study by Montreal researchers shows regular cannabis use is associated with an increase in violent behaviour among young adults after discharge from a psychiatric hospital.
The study followed 1,136 patients between the ages of 18 and 40 for a year once they were released. More than 60 per cent were men.
Conducted by the Institut en Santé Mentale de Montréal (Montreal Institute of Mental Health), the study found that pot use in people with severe mental illness — schizophrenia, bipolar, psychotic and depressive disorders — can lead to crime and violence.
To be clear, said lead researcher Dr. Alexandre Dumais, a psychiatrist at the Philippe-Pinel Institute and associate professor at the Université de Montréal, they’re talking about serious aggressive behaviour from assault with a knife to rape.
While previous research established a link between marijuana use and violent behaviour, the nature of the relationship wasn’t clear. This study shows that with chronic use, the longer