Cognitive trajectories following onset of psychosis: a meta-analysis
Open Access
- 23 September 2022
- journal article
- review article
- Published by Royal College of Psychiatrists in The British Journal of Psychiatry
- Vol. 221 (6), 714-721
- https://doi.org/10.1192/bjp.2022.131
Abstract
Cognitive impairment is a core feature of schizophrenia, associated with poor functional outcomes. The course of cognitive function in the years following illness onset has remained a subject of debate, with a previous analysis finding no worsening, providing support for the neurodevelopmental model of schizophrenia. Since then, many more studies have reported on longitudinal cognitive performance in early psychosis, with some indicating deterioration, which does not align with this view. This study aims to quantitatively review the literature on the longitudinal trajectory of cognitive deficits in the years following psychosis onset, in comparison with healthy controls. It is the first to also synthesise longitudinal data on social cognition. Electronic databases (‘PubMed’, ‘PsycInfo’ and ‘Scopus’) were searched (to end September 2021). Meta-analyses of 25 longitudinal studies of cognition in early psychosis were conducted (1480 patients, 789 health controls). Unlike previous analyses, randomised controlled trials and those with multiple cognitive testing periods within the first year were excluded to minimise bias (PROSPERO, ID: CRD42021241525). Small improvements were observed for global cognition (g = 0.25, 95% CI 0.17–0.33) and individual cognitive domains, but these were comparable with healthy controls and likely an artefact of practice effects. There is no evidence of continued cognitive decline or improvement in the early years following psychosis onset, with a need for more studies over longer follow-up periods. Practice effects highlight the importance of including control samples in longitudinal and intervention studies. Further data are needed to evaluate the course of social cognition subdomains.Keywords
This publication has 73 references indexed in Scilit:
- The Myth of Schizophrenia as a Progressive Brain DiseaseSchizophrenia Bulletin, 2012
- Static and Dynamic Cognitive Deficits in Childhood Preceding Adult Schizophrenia: A 30-Year StudyAmerican Journal of Psychiatry, 2010
- IQ as a predictor of functional outcome in schizophrenia: A longitudinal, four-year study of first-episode psychosisSchizophrenia Research, 2009
- Neuropsychological course in the prodrome and first episode of psychosis: Findings from the PRIME North America Double Blind Treatment StudySchizophrenia Research, 2008
- The course of neurocognitive functioning in first-episode psychosis and its relation to premorbid adjustment, duration of untreated psychosis, and relapseSchizophrenia Research, 2007
- Longitudinal studies of cognition and functional outcome in schizophrenia: implications for MATRICSSchizophrenia Research, 2004
- Measuring inconsistency in meta-analysesBMJ, 2003
- Implications for the Neural Basis of Social Cognition for the Study of SchizophreniaAmerican Journal of Psychiatry, 2003
- Neurocognitive deficit in schizophrenia: A quantitative review of the evidence.Neuropsychology, 1998
- Stability of cognitive functioning early in the course of schizophreniaSchizophrenia Research, 1994