Long COVID patients have similar brain activity to those with dementia, UK researchers find

Some patients with COVID see similar brain changes to people with such neurodegenerative disorders as Alzheimer’s, according to University of Kentucky researchers.

As the COVID pandemic raged across the world in 2020, researchers came together to start better understanding the new disease. At UK, Yang Jiang, a professor in the Department of Behavioral Science, led a study digging into the long-term effects of the virus.

“We’re together trying to understand how the COVID virus goes from getting into the nose and the lung, to somehow affecting the heart and the brain,” she said.

“We think there may be a long COVID, which we still don’t totally understand. It’s likely a risk factor for other neurodegenerative diseases.”

Looking at the effects of long COVID, Jiang sought help from the UK Sanders Brown Center on Aging to better understand the lingering mental effects of the virus.

“They understand some of the neuroinflammatory processes and how oxygen and blood will go through the blood brain barrier and interact with the virus, and how that alters brain functions,” she said. “So we began to sort of put two sides of evidence together.”

Chris Norris, a professor in the Department of Pharmacology and Nutritional Sciences and researcher at the Sanders Brown Center, said they were able to find brain cells, called astrocytes, in people diagnosed with COVID reacting similarly to brain cells of people with neurodecline.

“(Astrocytes) regulate blood flow to the brain, they regulate the shuttling of metabolites from the blood to the neurons, they support synaptic connections in the brain. When astrocytes become reactive and inflamed, like they do in COVID, all of those things – the metabolism, the blood flow, the synaptic communication – are adversely affected,” he said.

Those same cells also affect blood flow. Alzheimer’s patients and long COVID patients could both experience decreased blood flow in the brain, said Bob Simpol, an assistant professor in the Department of Pharmacology and Nutritional Sciences and researcher at the Sanders Brown institute.

He called COVID a “risk factor” that could contribute to long-term cognitive impairment or neurodegeneration.

People experiencing inflammation of astrocytes will see symptoms like brain fog, lapses in memory or forgetting the name of common items. Norris said these symptoms go beyond misplacing your keys, to something more serious – like forgetting you had your keys to begin with.

The research also showed that the brains of people with long COVID had similar electroencephalography (EEG) patterns to people with dementia.

Jiang said EEG’s measure “brain age” by looking at the activity of brain waves.

“Our brain is active all the time, even when you’re resting and when you sleep. EEG can capture the synchronized neural activity at the scalp. So what we observed, in COVID-19 patients, is the same pattern we see in dementia patients, which is the brain literally slows down,” Jiang said.

A COVID diagnosis does not mean you have dementia. Instead, people who have been diagnosed with COVID should have their brain function checked regularly, to catch signs of deterioration early and promote intervention.

With early intervention, 40-60% of neurodegeneration symptoms are reversible, Jiang said. With this research, the team is pushing for patients who have had a COVID diagnosis to get regular neurological check-ups.

“You can now look at brain function pretty easily and non invasively with EEG, just as easily as taking your blood pressure or listening to your lungs,” Norris said.

“After your symptomatic, it may be a good idea to have your brain activity assessed.”