London, UK – A recent study suggests that individuals who contract Covid-19 may experience a decrease in intelligence, with those who have severe infections showing the most significant reduction in IQ. Researchers from Imperial College London analyzed data from over 112,000 volunteers who underwent Covid tests during the pandemic.
The study found that individuals who were hospitalized with severe Covid-19 exhibited an average drop of nine IQ points compared to those who did not contract the virus. Even those who experienced mild symptoms or long Covid, with persistent symptoms like ‘brain fog,’ showed decreases in cognitive ability – six and two points lower, respectively.
Lead author of the study, Professor Adam Hampshire, published the findings in The Lancet medical journal. The research attempted to control for other variables by closely matching participants in different groups for comparison.
Interestingly, the study revealed that individuals infected with the original Covid strain suffered a more substantial decrease in IQ compared to those infected with the Omicron variant. Vaccination against Covid-19 appeared to have a protective effect, mitigating cognitive declines associated with the virus.
According to Professor Hampshire, the long-lasting cognitive impacts of Covid-19 are concerning, with noticeable effects persisting in individuals infected a year or more earlier. The study, conducted as part of Imperial College’s React study, has prompted caution in interpreting the results due to the lack of pre-infection comparisons for the participants.
While some researchers suggest that there may be a distinctly affected group of individuals, Professor Benedict Michael from the University of Liverpool’s infection neuroscience laboratory acknowledges the lack of convincing evidence suggesting widespread cognitive decline in the population.
Other studies examining pre-and post-pandemic brain scans indicate that Covid-19 can impact brain function, even in individuals who were not hospitalized. The study does not attribute the impact to the virus directly infecting the brain but rather to secondary consequences of the infection affecting blood vessels and reducing oxygen flow. The extent of recovery for Covid patients’ brains remains uncertain.