What the study found
Cognitive impairment in substance-induced psychotic disorder and schizophrenia spectrum disorders may be quite similar. The meta-analysis also found a subtle but significant difference in executive functions, favoring substance-induced psychotic disorder.
Why the authors say this matters
The authors conclude that harmful substance use leading to psychosis may cause cognitive impairment as severe as that seen in schizophrenia. The findings also suggest that differences in executive functioning, a set of mental skills used for planning and control, may help distinguish schizophrenia from substance-induced psychotic disorder.
What the researchers tested
The researchers conducted a meta-analysis of comparative studies, systematically searching PubMed, Web of Science, and Google Scholar. They included studies that compared cognitive functioning between schizophrenia spectrum disorders and substance-induced psychotic disorder, assessed risk of bias with QUADAS-2, and pooled results with a random-effects model after converting reported means and standard deviations to Hedges’ g.
What worked and what didn't
Eighteen studies with 1,092 patients were included. The overall random-effects meta-analysis showed no overall effect, while domain-level analysis found a subtle but significant difference in executive functions favoring substance-induced psychotic disorder. Performance was comparable between groups for memory, attention, psychomotor speed, and intellectual functioning.
What to keep in mind
The abstract does not describe limitations in detail beyond the use of comparative studies and the pooled meta-analytic approach. The findings are based on the studies included in the review and on the cognitive domains reported there.
Key points
- The review included 18 comparative studies with 1,092 patients.
- Overall cognitive performance was described as similar between the two groups.
- A subtle but significant difference was found in executive functions, favoring substance-induced psychotic disorder.
- Memory, attention, psychomotor speed, and intellectual functioning were comparable between groups.
- The authors conclude that substance-related psychosis may cause cognitive impairment as severe as schizophrenia.
Disclosure
- Research title:
- Substance-induced psychosis and schizophrenia show similar cognitive impairment
- Authors:
- Irena Semančíková, Filip Děchtěrenko, Pooja Patel, Ondřej Bezdíček
- Institutions:
- Charles University, Psychiatrická Nemocnice Bohnice, General University Hospital in Prague, VA Greater Los Angeles Healthcare System
- Publication date:
- 2026-04-06
- OpenAlex record:
- View
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