Pandemic linked to faster brain ageing in healthy adults

People who never caught COVID-19 still showed signs of faster brain ageing during the pandemic, with scans revealing an average increase of 5.5 months in a recent study

The researchers used brain imaging to assess structural brain changes in adults who lived through the pandemic compared to those who had scans before it began.

They found a widening of the “brain age gap”—the difference between predicted brain age on scans and actual age—among those scanned during the pandemic.

Both groups had similar baseline health profiles.

The greatest changes were seen in older adults, men and people from socioeconomically deprived backgrounds, especially those with lower education, employment levels or poorer health—regardless of whether they had been infected.

The researchers noted that brain ageing was more pronounced in COVID-positive participants and was linked to cognitive decline, suggesting that infection-related factors may contribute to reduced brain resilience.

The team wrote: “This supports the concept of brain resilience loss leading to faster cognitive decline, consistent with existing neurodegeneration and dementia research and recent epigenetic models.”

The team from the University of Nottingham examined data from 15,334 healthy adults in the UK Biobank study, with an average age of 63.

Less than 4 per cent had been hospitalised, and all tested negative for COVID-19 at least three weeks after infection.

The study focused on 996 healthy adults—average age 58.8—who had two MRI scans: either both before the pandemic or one before and one after the emergence of COVID-19.

Accelerated brain ageing was only associated with measurable declines in memory, attention and problem-solving among people who had been infected.

Non-infected participants showed structural changes but not cognitive deterioration.

The authors explained that these effects may not immediately result in symptoms.

Lead author Ali-Reza Mohammadi-Nejad said: “Some changes do not trigger symptoms, and some others take many years for any symptom to be manifested.”

They suggested that lifestyle changes during the pandemic—such as reduced physical activity, poorer nutrition and higher alcohol intake—may also have contributed to the observed changes.

Commenting on the findings, Mahdi Moqri of Harvard Medical School said: “Really underlines how significant the pandemic environment was for mental and neurological health.”

He noted that only two scanning timepoints were available, meaning it remains uncertain whether the changes are reversible.

The researchers said the findings “highlight the pandemic’s significant impact on brain health, beyond direct infection effects, emphasising the need to consider broader social and health inequalities.”

They plan further research to explore whether the pandemic environment directly caused premature brain ageing and to assess whether the effects persist long term.