A new, landmark study published in JAMA Psychiatry demonstrates a strong association between hallucinogen use, including the use of LSD and ecstasy, and increased risks for the development of schizophrenia. In this study, multiple investigators at lead Canadian institutions including ICES, The Ottawa Hospital, and the University of Ottawa followed individuals above 9.2 million for 13 years in Ontario, Canada. Such researchers estimated, in fact, that visitors to ED for hallucinogen-related problems had a 21-fold increased risk of receiving a schizophrenia diagnosis compared with the general population.
As the study showed, even when controlling for other factors such as the history of mental health and substance use, patients whose ED visits were related to the use of hallucinogens were as high as 3.5 times more likely than others to eventually be diagnosed with schizophrenia. Of those, over the next three years following these hallucinogen-related ED visits, 4% of them had a diagnosis of schizophrenia against 0.15% in the general population. The study has raised an alarm regarding the psychiatric effects of psychedelics gaining playground popularity both for recreation and experimental therapy.
Such a study has its origins in the increasingly popular use of psychedelics that is taking place in North America, both recreationally and clinically. According to data from last year, 9% of American adults between ages 19 and 30 reported using hallucinogens in 2023-a figure that has more than doubled from 5% in 2017. For adults between ages 35 and 50, it has also doubled-from 2% in 2021 to 4% this year. Meanwhile, the annual rate of hallucinogen-related ER visits across Ontario increased 86% between 2013 and 2021.
According to Dr. Daniel Myran, a quick-publishing researcher and Canada Research Chair in Social Accountability at the University of Ottawa, despite the growing enthusiasm about psychedelics in treating mental health, these drugs have the potential for harms. “Clinical trials of psychedelic-assisted therapy have safeguards, such as excluding people with a personal or family history of schizophrenia and monitoring participants very closely,” Dr. Myran said.
This degree of caution is seldom seen in recreational settings, since users are unsupervised medically and might not even know about predispositions that make them vulnerable to the conditions above. These findings put into perspective the fact that while psychedelics may, indeed, have some potential in therapeutic settings, especially in the case of treatment-resistant psychiatric conditions, they also bear risks. The researchers specified that their study does not prove a cause-and-effect action between psychedelics and schizophrenia but rather acted along the lines of serving as a warning.
“Our findings provide a timely caution about potential risks of hallucinogen use outside trial settings,” Dr. Myran said. While much hype has surrounded psychedelic-assisted therapy, experts urge balance in understanding possible benefits and risks. “While there is enormous enthusiasm for psychedelic-assisted therapy as a new mental health treatment, we need to remember how early and limited the data remains for both the benefits and the risks,” Dr. Myran added, calling for more research on the long-term effects brought on by various hallucinogens.
