In a recent study assessing the risk of developing schizophrenia, 9,844,497 individuals aged 16 to 65 (mean age [SD] 40.2 [14.7]; 50.2% female) without a history of psychosis were assessed for the likelihood of transitioning to schizophrenia following an episode of substance-induced psychosis. Out of this population, 407,737 (4.1%) individuals were admitted to the emergency department (ED) for a substance-related incident. Of these ED visits, 13,784 (3.4%) were admitted for substance-induced psychosis. When comparing individuals admitted to the ED for substance-induced psychosis to the general population, individuals admitted for substance-induced psychosis had a 163-fold increased risk of transitioning to schizophrenia. Individuals with an ED visit for substance use without psychosis were less likely to transition to schizophrenia than those admitted for substance-induced psychosis, but 3 times the number of individuals admitted to the ED for substance use without psychosis transitioned to schizophrenia compared to the general population. Cannabis use resulted in the highest number of transitions to schizophrenia among substance-induced psychosis visits and was the third-highest risk among visits without psychosis. Younger males were most likely to transition to schizophrenia, particularly for cannabis use.

Reference:

Myran, D. T., et al. JAMA Psychiatry. Epub ahead of print. Abstract