COVID-19 can affect people’s cognitive and memory abilities for more than a year after infection.
A new study by researchers at Imperial College London shows that people who have recovered from COVID-19 perform slightly less well on cognitive and memory tasks compared to people who have not had COVID-19. It became clear that there were some flaws.
This includes people who had long-term symptoms (i.e. long-term COVID-19 infection) and eventually recovered.
The study also showed that cognitive impairment was greater in people who were hospitalized, had long-term symptoms, or were infected with earlier variants of the virus.
The study was published today in the New England Journal of Medicine.
large group study
The Empire-led study, called REACT Long COVID, enrolled more than 140,000 participants who completed at least one cognitive task, many of whom had experienced COVID-19 at varying levels of severity and persistence. ing.
Participants in this study were asked to perform an innovative online cognitive assessment on the Cognitron platform. This assessment consists of tasks that can detect subtle changes in various aspects of brain function, including memory, reasoning, executive function, attention, and impulsivity.
The large scale of the study and the sensitivity of the computerized test allowed for a very detailed examination of factors explaining post-COVID-19 cognitive impairment while controlling for population variables such as age, demographics, and pre-existing medical conditions. I was able to do.
cognitive findings
The study revealed small defects that were detectable even in people with a short illness, even more than a year after infection. This value is lower in people who have had symptoms for more than 12 weeks (consistent with long-term coronavirus), who have been to the hospital sick, or who have been infected with one of the early variants of the SARS-CoV-2 virus. It was bigger.
However, those whose symptoms lasted longer but resolved by the time cognitive assessment was performed showed smaller deficits that were similar in size to those who had a shorter duration of illness.
The potential long-term effects of COVID-19 on cognitive function are a concern to the public, health care professionals, and policy makers, but until now they have not been objectively evaluated in large population samples. It was difficult to measure it accurately. Professor Adam Hampshire Study co-author from Imperial Neuroscience Department
The results showed that COVID-19 is associated with deficits in multiple areas of cognition, including the ability to recall pictures of objects seen minutes ago. Researchers believe this may be due to problems forming new memories, rather than accelerated forgetting.
They also showed slight deficits in some tasks that test executive and reasoning abilities, such as tasks that require spatial planning or verbal reasoning.
Professor Adam Hampshire, from the Department of Neuroscience at Imperial College London, lead author of the study, said: But until now, it has been difficult to measure them objectively in large population samples.
“By measuring various aspects of cognition and memory at scale using our online platform, we were able to detect small but measurable deficits in the performance of cognitive tasks. We also know that people can be affected in different ways depending on factors such as duration, virus variants and hospitalization.”
Impact reduction
Professor Paul Elliott, senior author and director of the REACT program from the School of Public Health at Imperial College London, said: Their cognitive function reaches a level similar to that of people who have experienced a short illness.
“Furthermore, the cognitive impact of COVID-19 appears to have diminished since the early stages of the pandemic, with fewer people suffering from persistent illness and a period when omicron was predominant. Cognitive effects were also lower among people infected with COVID-19. However, given the large number of infected people, we will continue to monitor the long-term clinical and cognitive effects of the COVID-19 pandemic. That will be important.”
“Cognition and memory following COVID-19 in a large community sample” by Hampshire, A. et al. was published in NEJM. DOI: https://doi.org/10.1056/NEJMoa2311330