Cognitive deficits in people who have recovered from COVID-19

Adam Hampshire; William Trender; Samuel R Chamberlain; Amy E Jolly; Jon E Grant; Fiona Patrick; Ndaba Mazibuko; Steve Cr Williams; Joseph M Barnby; Peter Hellyer; Mitul A Mehta

doi:10.1016/j.eclinm.2021.101044

Cognitive deficits in people who have recovered from COVID-19

EClinicalMedicine. 2021 Sep:39:101044. doi: 10.1016/j.eclinm.2021.101044. Epub 2021 Jul 23.

Authors

Adam Hampshire¹, William Trender¹, Samuel R Chamberlain^{2

3}, Amy E Jolly¹, Jon E Grant⁴, Fiona Patrick⁵, Ndaba Mazibuko⁵, Steve Cr Williams⁵, Joseph M Barnby⁵, Peter Hellyer^{1

5}, Mitul A Mehta⁵

Affiliations

¹ Department of Brain Sciences, Dementia Research Institute Care Research and Technology Centre, Imperial College London, 926, Sir Michael Uren Hub 86 Wood Lane, London, W12 0BZ.
² Department of Psychiatry, University of Southampton, United Kingdom.
³ Department of Psychiatry, University of Cambridge, United Kingdom.
⁴ Department of Psychiatry, University of Chicago, United States.
⁵ Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.

Abstract

Background: There is growing concern about possible cognitive consequences of COVID-19, with reports of 'Long COVID' symptoms persisting into the chronic phase and case studies revealing neurological problems in severely affected patients. However, there is little information regarding the nature and broader prevalence of cognitive problems post-infection or across the full spread of disease severity.

Methods: We sought to confirm whether there was an association between cross-sectional cognitive performance data from 81,337 participants who between January and December 2020 undertook a clinically validated web-optimized assessment as part of the Great British Intelligence Test, and questionnaire items capturing self-report of suspected and confirmed COVID-19 infection and respiratory symptoms.

Findings: People who had recovered from COVID-19, including those no longer reporting symptoms, exhibited significant cognitive deficits versus controls when controlling for age, gender, education level, income, racial-ethnic group, pre-existing medical disorders, tiredness, depression and anxiety. The deficits were of substantial effect size for people who had been hospitalised (N = 192), but also for non-hospitalised cases who had biological confirmation of COVID-19 infection (N = 326). Analysing markers of premorbid intelligence did not support these differences being present prior to infection. Finer grained analysis of performance across sub-tests supported the hypothesis that COVID-19 has a multi-domain impact on human cognition.

Interpretation: Interpretation. These results accord with reports of 'Long Covid' cognitive symptoms that persist into the early-chronic phase. They should act as a clarion call for further research with longitudinal and neuroimaging cohorts to plot recovery trajectories and identify the biological basis of cognitive deficits in SARS-COV-2 survivors.

Funding: Funding. AH is supported by the UK Dementia Research Institute Care Research and Technology Centre and Biomedical Research Centre at Imperial College London. WT is supported by the EPSRC Centre for Doctoral Training in Neurotechnology. SRC is funded by a Wellcome Trust Clinical Fellowship 110,049/Z/15/Z. JMB is supported by Medical Research Council (MR/N013700/1). MAM, SCRW and PJH are, in part, supported by the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London.

Keywords: Attention; COVID-19; Cognition; Deficits; Long covid; Memory; Online assessment; Planning; Reasoning.