Your Brain Aged During The Pandemic, Even If You Didn't Get COVID

Researchers have discovered that both COVID-19 infection and the stress caused by the pandemic can accelerate brain aging. Even those who were not infected but lived through the pandemic showed signs of faster brain aging. The effects were more intense in men and those in more vulnerable social situations. Among those infected, there was also a decline in memory and reasoning. These findings show that the pandemic has impacted brain health broadly and unevenly.

In addition to the well-known respiratory symptoms caused by COVID-19, many studies indicate that the SARS-CoV-2 virus can also directly affect the brain and nervous system. This means it is neurotropic, meaning it has the ability to invade and impact brain tissue.

Several COVID-19 survivors have reported symptoms that persist for months, such as constant fatigue, difficulty concentrating, memory loss, anxiety, depression, and even post-traumatic stress disorder.

Recent research has shown possible links between COVID-19 infection and a decline in cognitive function, as well as visible changes in brain structure and molecular signs similar to those of brain aging. Significant psychological distress has also been observed during the pandemic, especially among young people and more vulnerable individuals, such as those living in disadvantaged social conditions.

Interestingly, other analyses revealed that, despite all the stress, the use of mental health services did not increase proportionally, and in the general population, there was no explosion in cases of mental disorders, except for a small increase in symptoms of depression, particularly among women.

Still, understanding the impact of the pandemic on brain health, taking into account whether or not a person has had COVID and their social circumstances, is essential to addressing the long-term effects on the population.

It is already known that the virus can remain in the body for several months, an average of 230 days, after infection and that it can directly invade the brain, cause damage to blood vessels, or trigger immune responses that affect the central nervous system. There is evidence that COVID-19 may accelerate brain aging processes and contribute to neurodegenerative diseases.

Studies using brain imaging, such as MRIs, have revealed that people who had COVID-19 experienced reduced thickness in key brain regions and loss of integrity in white matter, areas linked to memory, reasoning, and emotions.

But what is even more striking is that, even without direct infection, the pandemic experience itself, with its isolation, constant stress, and changes in routine and lifestyle, may have negatively impacted brain aging, especially among the elderly and those experiencing financial hardship.

To investigate this precisely, researchers at the UK Biobank used brain imaging data collected before and after the pandemic. They trained artificial intelligence models capable of estimating "brain age" based on various parameters extracted from the images. These models allowed them to compare whether a person's brain aged faster than expected based on their actual age.

Using this approach, the scientists analyzed data from nearly a thousand participants with two brain MRI scans: one group with scans performed before and after the pandemic, and another with scans performed only before the start of the health crisis.

They found that the brains of people exposed to the pandemic aged, on average, 5.5 months more than the brains of the control group. This means that brain aging was accelerated, even among people who had not had COVID-19.

Effects of sociodemographic factors, represented by deprivation indices, on brain aging in participants grouped by pandemic status. Each clock represents the difference in the mean rate of change in brain age difference (BAG) between individuals with low and high levels of specific sociodemographic factors. The clocks are presented separately for the gray matter (GM) and white matter (WM) models, with one set representing participants in the No Pandemic group and another representing participants in the Pandemic group. The sociodemographic factors studied include housing scores, health scores, employment scores, income scores, and education scores.

The impact was even stronger in men and in people from disadvantaged social backgrounds. However, among those who had COVID-19, this acceleration in brain aging was also accompanied by a worsening of cognitive performance, such as difficulties with memory, attention, and reasoning.

These results demonstrate that the effects of the pandemic go far beyond the virus infection itself and affect different social groups unequally. Therefore, researchers emphasize the importance of considering social, economic, and mental health aspects when assessing the pandemic's impact on brain health. This is essential for developing more effective and inclusive public policies for the population's post-pandemic recovery.

READ MORE:

Accelerated brain ageing during the COVID-19 pandemic

Ali-Reza Mohammadi-Nejad, Martin Craig, Eleanor F. Cox, Xin Chen, R. Gisli Jenkins, Susan Francis, Stamatios N. Sotiropoulos, and Dorothee P. Auer

Nature Communications. 16, 6411. 22 July 2025

DOI: 10.1038/s41467-025-61033-4

Abstract: 

The impact of SARS-CoV-2 and the COVID-19 pandemic on brain health is recognised, yet specific effects remain understudied. We investigate the pandemic’s impact on brain ageing using longitudinal neuroimaging data from the UK Biobank. Brain age prediction models are trained from hundreds of multi-modal imaging features using a cohort of 15,334 healthy participants. These models are then applied to an independent cohort of 996 healthy participants with two magnetic resonance imaging scans: either both collected before the pandemic (Control groups), or one before and one after the pandemic onset (Pandemic group). Our findings reveal that, even with initially matched brain age gaps (predicted brain age vs. chronological age) and matched for a range of health markers, the pandemic significantly accelerates brain ageing. The Pandemic group shows on average 5.5-month higher deviation of brain age gap at the second time point compared with controls. Accelerated brain ageing is more pronounced in males and those from deprived socio-demographic backgrounds and these deviations exist regardless of SARS-CoV-2 infection. However, accelerated brain ageing correlates with reduced cognitive performance only in COVID-infected participants. Our study highlights the pandemic’s significant impact on brain health, beyond direct infection effects, emphasising the need to consider broader social and health inequalities.