Pandemic accelerated brain aging, study says

A new study has revealed that living through the Covid-19 pandemic has aged people's brains, regardless of whether they were infected with the disease.

The research adds to growing data on the long-term impact of the pandemic on global health and brain development.

The study showed that the pandemic accelerated brain aging by an average of 5.5 months. The changes were more noticeable in older people, men and people from more disadvantaged socioeconomic backgrounds.

Brain age is related to cognitive function and can be distinct from a person's actual age.

A person's brain age can be delayed or accelerated by diseases such as diabetes, HIV, and Alzheimer's disease. Premature brain aging can affect memory, sensory function, and emotional function. The authors state that the observed brain aging may be reversible.

"The pandemic has put pressure on people's lives, especially those who were already facing disadvantages. We can't yet test whether the changes we observed will be reversed, but it's certainly possible, and that's an encouraging thought," said study co-author Dorothee Auer , a neuroscientist at the University of Nottingham in the United Kingdom.

Frank Slack, director of the Harvard Cancer Research Institute in the US, said the "work is a tour de force demonstrating, in a large population, that Covid-19 has had serious effects on brain health, especially in men and the elderly." Slack was not involved in the study.

The study was published in the journal Nature Communications .

Did the pandemic affect people's brain function?

The study aimed to investigate the adverse effects of Covid-19 on physical and cognitive brain aging, using brain imaging and cognitive tests.

Researchers analyzed brain scans of healthy adults, taken before and after the pandemic.

“This gave us a rare opportunity to observe how major life events can affect the brain,” said Stamatios Sotiropoulos, a neuroscientist at the University of Nottingham and co-author of the study.

First, researchers used brain scan data from 15,334 healthy people to train a machine learning algorithm that could accurately estimate their brain age.

They then used the model to predict the brain age of 996 healthy adults before and after the Covid-19 pandemic.

One group of participants underwent CT scans before and after the start of the pandemic, while another group was only scanned before the outbreak.

Even the brains of those who did not have Covid were affected

The study found that the brains of participants in the pandemic group aged an average of 5.5 months faster than the control group, even when matched for a range of health markers.

Jacobus Jansen, a neuroscientist at UMC in Maastricht, the Netherlands, said that the surprising result was that “aging is independent of actual Covid-19 infection” .

However, only participants infected with Covid-19 showed declines in cognitive abilities such as mental flexibility and processing speed. This may suggest that the effects of brain aging during the pandemic in non-infected individuals may not cause noticeable cognitive symptoms.

The next question researchers are seeking to answer is how the pandemic has had long-term effects on people's cognitive health. Other studies have suggested that certain genetic factors may make some people more predisposed to Covid-19-related brain aging.

"In 2022, we described premature aging in the brains of patients with severe COVID-19. Unfortunately, all the patients we examined died of COVID-19, making detailed monitoring and analysis of brain architecture over time impossible," Slack said.

“It will be interesting to begin to ask whether the aging effects observed in this study are related to the changes in gene expression that we observed in our study,” Slack said.

Is it possible to reverse brain aging?

Neuroscience studies suggest that there are ways to slow brain aging and reduce the risk of cognitive decline.

Physical exercise, for example, is a known protective factor in brain aging, which is why “it would be valuable to evaluate the contribution of changes in exercise patterns during the pandemic, along with psychological stress, within the model,” said Maria Mavrikaki, a neuroscientist at Harvard Medical School, USA, who was not involved in the study.

Other studies suggest that brain aging can be slowed by lifestyle changes, such as maintaining a healthy diet, staying physically and mentally active, managing stress, and getting enough sleep, which promote healthy brain aging.

These small changes can add up, so incorporating them into your routine can help your brain function in the future.