Citation

Vassos E. Am. J. Psychiatry 2023; 180(6): 404-406.

Copyright

(Copyright © 2023, American Psychiatric Association)

DOI

10.1176/appi.ajp.20230298

PMID

37259511

Abstract

New-onset psychosis is always disconcerting and alarming for patients, families, and clinicians. Although some acute psychotic disorders are brief and resolve in a short period of time, others progress to schizophrenia or bipolar disorder and have a long-term impact on people's mental health and quality of life. Substance-induced psychotic disorders are brief psychotic syndromes triggered by substance use that persist for days or weeks after intoxication has resolved. Abundant evidence suggests that individuals presenting to mental health services with substance-induced psychotic disorders have a significant risk of later transition to schizophrenia or, more generally, to a chronic psychotic disorder. A recent meta-analysis (1) of 25 studies providing substance-specific estimates of transition to schizophrenia spectrum disorders among more than 34,000 individuals with substance-induced psychotic disorder estimated a pooled transition rate of 25% across all substances, with differential rates depending on the substance.

Population-based register studies may provide more accurate estimates of transition rates than studies of research cohorts because of larger and more representative sampling and longer follow-up periods. In this context, large studies using national registers have been conducted in Scandinavia and Scotland (2-5). These studies confirm that a considerable number of patients with an initial diagnosis of substance-induced psychotic disorder receive a later diagnosis of schizophrenia or schizophrenia spectrum disorder, although the reported transition rates differed across studies. This is partly attributable to differences in the recruitment of patients with substance-induced psychotic disorder (for example, studies restricted to inpatients reported higher transition rates), possible differences in the exclusion of individuals with prodromal schizophrenia from the group with substance-induced psychotic disorder, and the definition of the outcome (narrowly defined schizophrenia or more broadly defined psychotic disorders). Despite these differences, common patterns were observed: men and people who developed substance-induced psychotic disorder early in life had a higher risk of later diagnosis of schizophrenia spectrum disorder, most transitions from substance-induced psychotic disorder to schizophrenia spectrum disorder occurred within the first 2-3 years, and cannabis- and alcohol-induced psychotic disorders had the highest and lowest transition rates, respectively, with other substances falling between the two...

Language: en

Keywords

Humans; Cannabis; Substance-Related and Addictive Disorders; *Psychotic Disorders/etiology; Bipolar and Related Disorders; Schizophrenia Spectrum and Other Psychotic Disorders; Substance-Induced Psychosis