Dr. Adam Hampshire PhD Faculty of Medicine Department of Brain Sciences Imperial College London

Brain Fog After COVID: Recovering Patients Underperformed on Cognitive Tests

MedicalResearch.com Interview with:

Dr. Adam Hampshire PhD Faculty of Medicine Department of Brain Sciences Imperial College London

Dr. Hampshire

Dr. Adam Hampshire PhD
Faculty of Medicine
Department of Brain Sciences
Imperial College London

MedicalResearch.com: What is the background for this study?

Response: During 2020 I was leading a study that sought to map the distribution of cognitive abilities and aspects of mental health across the UK population. The study generated a lot of interest because it was a collaboration with BBC2 Horizon, leading to ~390,000 participants.

When the pandemic began to escalate in the UK a number of my colleagues at Imperial and elsewhere contacted me to note that the study could be used to investigate the impact of both the pandemic and direct illness on daily life, mental health and cognition. I had been thinking along similar lines so decided to add questionnaires about peoples’ experiences with the pandemic and Covid-19 illness.

MedicalResearch.com: What are the main findings?

Response: The results showed a worrying association whereby people who had recovered from Covid-19 underperformed on the cognitive tests. Because we had so many participants, our analyses were able to account for many population variables known to correlate with cognition, for example, age, first language, education level and pre-existing medical condition. The association with Covid-19 remained, which means it was unlikely to be due to people who became ill having had lower baseline cognitive abilities. The association scaled with severity of respiratory symptoms and it was greater for people who had positive biological tests confirming Covid-19 illness, that is, as opposed to suspected illness. This latter result is interesting as it indicates that other common respiratory illnesses are unlikely to have the same association with cognition. Underperformance was particularly pronounced for aspects of ‘higher’ cognition such as reasoning, planning and word-based problem solving.

MedicalResearch.com: What should readers take away from your report?

Response: It is important to be cautious in how we interpret the results of this study in isolation. We observed a worrying cross-sectional association of Covid-19 illness with cognitive performance some months post recovery and we ruled out many potentially confounding factors such as age and education level. However, it remains unclear what the basis of the correlation is or how long any impact on cognition might last. Taken in context, the results add to the emerging body of research reporting ‘brain fog’ and ‘problems finding the words’ in the months after being ill.

MedicalResearch.com: What recommendations do you have for future research as a result of this work?

Response: We need large scale longitudinal research to determine how long any cognitive deficits post covid illness last. Also, more research is needed to understand how aspects of cognition correlate with neuroimaging measures of brain structure and function as well as other emerging correlates of long covid such as insomnia, post-traumatic stress symptoms and fatigue.

No disclosures. 


Cognitive deficits in people who have recovered from COVID-19 relative to controls: An N=84,285 online study
Adam Hampshire, William Trender, Samuel R Chamberlain, Amy Jolly, Jon E. Grant, Fiona Patrick, Ndaba Mazibuko, Steve Williams, Joseph M Barnby, Peter Hellyer, Mitul A Mehta
medRxiv 2020.10.20.20215863; doi: https://doi.org/10.1101/2020.10.20.20215863

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Last Updated on July 28, 2021 by Marie Benz MD FAAD