Background Studies investigating cognitive impairments in psychosis and depression have typically compared the average performance of the clinical group against healthy controls (HC), and do not report on the actual prevalence of cognitive impairments or strengths within these clinical groups. This information is essential so that clinical services can provide adequate resources to supporting cognitive functioning. Thus, we investigated this prevalence in individuals in the early course of psychosis or depression. Methods A comprehensive cognitive test battery comprising 12 tests was completed by 1286 individuals aged 15-41 (mean age 25.07, s.d. 5.88) from the PRONIA study at baseline: HC (N = 454), clinical high risk for psychosis (CHR; N = 270), recent-onset depression (ROD; N = 267), and recent-onset psychosis (ROP; N = 295). Z-scores were calculated to estimate the prevalence of moderate or severe deficits or strengths (>2 s.d. or 1-2 s.d. below or above HC, respectively) for each cognitive test. Results Impairment in at least two cognitive tests was as follows: ROP (88.3% moderately, 45.1% severely impaired), CHR (71.2% moderately, 22.4% severely impaired), ROD (61.6% moderately, 16.2% severely impaired). Across clinical groups, impairments were most prevalent in tests of working memory, processing speed, and verbal learning. Above average performance (>1 s.d.) in at least two tests was present for 40.5% ROD, 36.1% CHR, 16.1% ROP, and was >2 SDs in 1.8% ROD, 1.4% CHR, and 0% ROP. Conclusions These findings suggest that interventions should be tailored to the individual, with working memory, processing speed, and verbal learning likely to be important transdiagnostic targets.
Bibliographical noteCopyright © The Author(s), 2023. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence
(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Funding Information: PRONIA is a Collaborative Project funded by the European Union under the 7th Framework Programme under grant agreement n° 602152 Funding Information: CP: Participated on Advisory Boards for Janssen-Cilag, AstraZeneca, Lundbeck, and Servier. Received honoraria for talks presented at educational meetings organised by AstraZeneca, Janssen-Cilag, Eli Lilly, Pfizer, Lundbeck, and Shire. NK and RS: Received honoraria for talks presented at education meetings organised by Otsuka/Lundbeck. RU: Received grants from the Medical Research Council, National Institute for Health Research: Health Technology Assessment, European Commission – Research: The Seventh Framework Programme, and personal speaker fees from Sunovion, outside the submitted work. TL: Supported by the Koeln Fortune Program/Faculty of Medicine, University of Cologne (Grant No. 370/2020). JW: Partly supported by the NARSAD Young Investigator Award of LK through the Brain & Behavior Research Foundation (grant number 28474). KA: Supported by a Dame Kate Campbell Fellowship from the University of Melbourne.
- Mental health
- verbal learning
- processing speed
- working memory