Researchers note decline in brain function in some COVID-19 survivors

People recovering from COVID-19 may suffer long-lasting impaired brain function, according to a non-peer-reviewed study of more than 84,000 people, led by Adam Hampshire, a doctor at Imperial College London.

Researchers found in some of the worst cases, patients experienced mental decline equivalent to the brain aging by 10 years. 

Of all patients studied, 60 reported being put on a ventilator, 147 were hospitalized but needed no ventilator, 176 received medical assistance at home, experiencing respiratory difficulties, 3,466 had respiratory issues but did not receive medical assistance, and 9,201 were ill without respiratory symptoms. The team said 361 self-reported having a positive biological test.

When analyzing data from the patients, study authors said they found significant cognitive decline in some individuals.

“[Cognitive deficits] were of substantial effect size for people who had been hospitalized, but also for mild but biologically confirmed cases who reported no breathing difficulty,” the researchers wrote in a post published on MedRxiv. “Finer grained analyses of performance support the hypothesis that COVID-19 has a multi-system impact on human cognition.”

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But experts not involved in the study told Reuters that findings should not be viewed as definitive, as the test did not measure for cognitive function pre-infection, and did not complete lengthy follow-up.

“Overall (this is) an intriguing but inconclusive piece of research into the effect of COVID on the brain,” Derek Hill, a professor of medical imaging science at University College London, told Reuters. “As researchers seek to better understand the long term impact of COVID, it will be important to further investigate the extent to which cognition is impacted in the weeks and months after the infection, and whether permanent damage to brain function results in some people.”

The team said their findings should prompt more research into cognitive deficits in people who have survived coronavirus.

Researchers have been studying the long-term effects of the coronavirus since reports surfaced of people experiencing an array of symptoms not listed on the U.S. Centers for Disease Control and Prevention’s website, lasting months. 

Some of the persistent symptoms include fatigue, brain fog, exhaustion, headaches, vertigo, shortness of breath, chest pain and muscle aches.

Dr. Mady Hornig, an immunologist and professor of epidemiology at Columbia University, has been researching the long-term effects of a viral infection like COVID-19.

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Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is an illness which impacts cognitive function, and has been found in patients who have recovered from coronaviruses such as SARS, according to Hornig. 

The CDC cites a 2015 report from the nation’s top medical advisory body, the Institute of Medicine, which says that an estimated 836,000 to 2.5 million Americans suffer from ME/CFS.

The CDC says that people with ME/CFS experience severe fatigue, sleep problems, as well as difficulty with thinking and concentrating while experiencing pain and dizziness.

FOX News contributed to this story.