Cognitive impairments are a core feature of psychotic disorders, but their long-term trajectory remains contentious. Previous meta-analyses were focused on the first 5 years following psychosis onset. Here, we evaluated the change in cognitive impairments in psychotic disorders through a meta-analysis of studies with follow-ups of 5+ years.
Following pre-registration (PROSPERO, CRD42023447589), databases were searched for relevant articles until July 2024. Two authors screened the reports for studies reporting on the change in cognitive impairments in global cognition, verbal learning and memory, visual learning and memory, working memory, attention, speed of processing, reasoning and problem-solving, and verbal fluency in individuals with psychotic disorders and with a minimum follow-up of 5 years. Three authors extracted data, and the PRISMA guidelines were followed. Random-effects model meta-analyses and moderator analyses were conducted to examine the robustness of the results.
Twenty-four studies comprising 2633 patients and 1019 controls were included in the study. Over an average of 8.46 years, cognitive impairments remained stable in patients in all 8 measures: global cognition (g = .09; 95% CI, .03-.20), verbal memory (g = .05; 95% CI, -.11, .21), visual memory (g =-.16; 95% CI, -.35, .04), working memory (g =.03; 95% CI, -.09, .14), attention (g =.22; 95% CI, -.36, .80), speed of processing (g =.10; 95% CI, -.14, .35), reasoning and problem-solving (g =.16; 95% CI, -.03, .35), and verbal fluency (g =.08; 95% CI, -.03, .20).
We conclude that cognitive impairments remain stable over time, consistent with the neurodevelopmental view of psychotic disorders.