Pandemic ‘aged our brains’ even if you never got COVID-19

By Stephen Beech

The COVID-19 pandemic aged our brains, even if we were never infected with the virus, according to new research.

The stress and strains of living through COVID-19 accelerated people’s brain health, say scientists.

The study showed that people who lived through the pandemic showed signs of faster brain aging over time than those scanned entirely before it.

The changes were most noticeable in older people, in men, and in those from more disadvantaged backgrounds, according to the findings published in the journal Nature Communications.

Only participants who were infected by COVID-19 between their scans showed a drop in certain cognitive abilities, such as mental flexibility and processing speed.

Researchers say that this may suggest that the pandemic’s brain aging effect, on its own, without infection, may not cause symptoms.

And they believe that the observed brain aging may be reversible.

The study was conducted by a team of experts from the University of Nottingham’s School of Medicine and was supported by the National Institute for Health and Care Research (NIHR) Nottingham Biomedical Research Centre and the Medical Research Council (MRC) DEMISTIFI programme.

Study leader Dr. Ali-Reza Mohammadi-Nejad said: “What surprised me most was that even people who hadn’t had COVID showed significant increases in brain aging rates.

"It really shows how much the experience of the pandemic itself, everything from isolation to uncertainty, may have affected our brain health.”

The researchers analysed brain scans from nearly 1,000 healthy adults, taken as part of the UK Biobank study.

Some participants had scans before and after the pandemic; others, only before.

Using advanced imaging and machine learning, the research team estimated each person’s “brain age” - how old their brain appeared to be compared to their actual age.

The brain age model was developed using brain scans from more than 15,000 healthy individuals, allowing the researchers to build an accurate model for estimating brain age.

Study senior author Professor Dorothee Auer said: “This study reminds us that brain health is shaped not only by illness, but by our everyday environment.

“The pandemic put a strain on people’s lives, especially those already facing disadvantage.

"We can’t yet test whether the changes we saw will reverse, but it’s certainly possible, and that’s an encouraging thought.”

Co-lead author Professor Stamatios Sotiropoulos added: “The longitudinal MRI data acquired before and after the pandemic from the UK Biobank gave us a rare window to observe how major life events can affect the brain.”