The COVID-19 pandemic started in March 2020 and caused a global shutdown for several months. Air travel was restricted, and only business travel was allowed. Every day, people anxiously awaited news of how many people had been infected with the SARS-CoV-2 virus.

Unfortunately, many people who contracted COVID-19 have experienced various complications. These include respiratory problems, issues with concentration, memory problems, sleep difficulties, deterioration of sleep quality, and what is commonly known as "COVID fog."

Medical experts from Imperial College London have published their findings in the New England Journal of Medicine scientific journal. They have found that brain fog is a real and significant issue, which can cause a decline of up to six IQ points.

"The potential long-term effects of COVID-19 on cognitive function have been a concern for the public, healthcare professionals, and policymakers, but until now, it has been difficult to objectively measure them in a large population sample," said Professor Adam Hampshire, co-author of the new study, in a media interview.

A team of experts from Imperial College London has analysed data from one of the world's most extensive and longest-running studies of SARS-CoV-2 and Covid-19. The study, which began in April 2020, has involved over three million participants from the UK. The research focused on the people affected by the "long tail" of COVID-19 symptoms and found that ‘brain fog’ is a real phenomenon that can have serious consequences.

The study on 'brain fog' was conducted online to measure cognitive abilities that COVID-19 impacts. The researchers compared the cognitive function results with the duration and severity of symptoms.

According to geekweek.interia.pl, between three and four per cent of the participants were categorised as long-term COVID-19 patients who reported symptoms lasting more than 12 weeks. What's more, the majority of this group of patients still experienced symptoms up to a year later.

"By using our online platform to measure multiple aspects of cognition and memory at a large scale, we were able to detect small but measurable deficits in cognitive task performance. We also found that people were likely affected in different ways depending on factors such as illness duration, virus variant and hospitalisation," the researchers explained in a media interview.

According to geekweek.interia.pl, the study discovered slight yet notable differences in cognitive abilities between those who contracted COVID-19 and those who did not. The decline in cognitive performance ranges from three to six IQ points, but it is important to note that this difference would not be noticeable in the daily life of an average person. However, at a population level, the scale of the pandemic may make such differences perceptible.

"Even if cognitive deficits after COVID-19 are of small magnitude on average, a substantial minority of people have more significant deficits which are likely to affect their ability to work and function. Given the scale of the pandemic and the number of people affected, this is particularly worrisome", the researchers report.

Source: geekweek.interia.pl, The Guardian