ORCID Profile
0000-0002-7598-2323
Current Organisation
University College London
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Publisher: Cold Spring Harbor Laboratory
Date: 19-03-2023
DOI: 10.1101/2023.03.14.23287211
Abstract: Cognitive impairment has been reported after many types of infection, including SARS-CoV-2. Whether deficits following SARS-CoV-2 improve over time is unclear. Studies to date have focused on hospitalised in iduals with up to a year follow-up. The presence, magnitude, persistence and correlations of effects in community-based cases remain relatively unexplored. Cognitive performance (working memory, attention, reasoning, motor control) was assessed in participants of a voluntary biobank in July, 2021 (Round 1), and April, 2022 (Round 2). Participants, drawn from the COVID Symptom Study smartphone app, comprised in iduals with and without SARS-CoV-2 infection and varying symptom duration. Effects of COVID-19 exposures on cognitive accuracy and reaction time scores were estimated using multivariable ordinary least squares linear regression models weighted for inverse probability of participation, adjusting for potential confounders and mediators. The role of ongoing symptoms after COVID-19 infection was examined stratifying for self-perceived recovery. Longitudinal analysis assessed change in cognitive performance between rounds. 3335 in iduals completed Round 1, of whom 1768 also completed Round 2. At Round 1, in iduals with previous positive SARS-CoV-2 tests had lower cognitive accuracy (N = 1737, β = −0.14 standard deviations, SDs) than negative controls. Deficits were largest for positive in iduals with ≥ 12 weeks of symptoms (N = 495, β = −0.22 SDs). Effects were comparable to hospital presentation during illness (N = 281, β = −0.31 SDs), and 10 years age difference (60-70 years vs. 50-60 years, β = −0.21 SDs) in the whole study population. Stratification by self-reported recovery revealed that deficits were only detectable in SARS-CoV-2 positive in iduals who did not feel recovered from COVID-19, whereas in iduals who reported full recovery showed no deficits. Longitudinal analysis showed no evidence of cognitive change over time, suggesting that cognitive deficits for affected in iduals persisted at almost 2 years since initial infection. Cognitive deficits following SARS-CoV-2 infection were detectable nearly two years post infection, and largest for in iduals with longer symptom durations, ongoing symptoms, and/or more severe infection. However, no such deficits were detected in in iduals who reported full recovery from COVID-19. Further work is needed to monitor and develop understanding of recovery mechanisms for those with ongoing symptoms. Chronic Disease Research Foundation, Wellcome Trust, National Institute for Health and Care Research, Medical Research Council, British Heart Foundation, Alzheimer’s Society, European Union, COVID-19 Driver Relief Fund, French National Research Agency. Abstracts were screened from a PubMed search query (COVID-19) AND (long COVID) AND (cognitive impairment), which returned 409 results between 2020 and January 20, 2023. Multiple systematic reviews and meta-analyses reported consistent observation of cognitive deficits following SARS-CoV-2 infection. Most studies of cognitive impairment have used small s les of less than 200 participants (including any controls), hospitalised cohorts, and measured cognitive impairment through self-report or dichotomised quantitative scales. Only one study was found with a s le size of more than 1,000 in iduals, included cases and controls across both community and hospital settings, and used objective cognitive testing that allowed quantitative estimation of the scale of any cognitive impairment. Previous studies have also been limited insofar as focusing on earlier infections in the first year of the COVID-19 pandemic, prior to introduction of vaccination and emerging variants. Studies focusing on longitudinal follow-up for those hospitalised with COVID-19 or with long COVID have found low rates of full recovery from long-term symptoms at up to one year since infection, including cognitive impairment. We report quantitatively on cognitive impairment following SARS-CoV-2 infection, from a large dataset of 4,000 in iduals with and without test-confirmed SARS-CoV-2 infection and a range of associated symptom durations, with mostly community-based cases. Importantly, we undertook two rounds of cognitive testing allowing longitudinal tracking of cognitive performance. Our longitudinal methods allowed us to report on deficits up to two years since infection, and following infections with SARS-CoV-2 variants that have emerged over 2021 and 2022, not previously studied in the context of COVID-19 and cognition. This study adds to existing evidence of cognitive deficits following SARS-CoV-2 infection, but finds important exceptions. At initial testing in mid-2021, cognitive deficits are not found for in iduals who self-report as feeling recovered from COVID-19, even for those with longest symptom duration. In follow-up testing in mid-2022, we find that deficits appear persistent for those with earlier infections and ongoing symptoms, consistent with previous smaller studies. More research is required to monitor those experiencing persistent cognitive impairment and understand the mechanisms underlying recovery.
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Khaled Rjoob.