Psychotic Disorders Rising in Younger Canadians Amid Higher Substance Use: Study

The annual incidence of psychotic disorders jumped by 60 percent among 14-20-year-olds between 1997 and 2023, according to the 30-year study.

Workers produce medical marijuana at Canopy Growth Corporation's Tweed facility in Smiths Falls, Ont., on Feb. 12, 2018. THE CANADIAN PRESS/Sean Kilpatrick

The incidence of psychotic disorders has increased among younger Canadians, a trend that could be linked to a rise in the rates of substance use such as cannabis, according to a Feb. 2 peer-reviewed study published in the Canadian Medical Association Journal (CMAJ).

Researchers analyzed health administrative data of more than 12.23 million people from Ontario born between 1960 and 2009. They looked at diagnoses of schizophrenia spectrum disorder (SSD) and psychosis not otherwise specified (NOS), collectively referred to as psychotic disorders. The study assessed outcomes among these individuals over a 30-year period between 1993 and 2023.