What you should know
- Just a mild COVID-19 infection can cause “profound” cellular effects in the brain with long-term impact on memory and executive function, according to a new study published Monday.
- The preliminary study found that people infected with COVID can frequently suffer neurological impacts similar to people who have undergone cancer treatment.
- The study adds to a growing body of evidence about what some are calling “COVID brain” or “COVID fog,” which scientists are still trying to fully understand, particularly how long it might last in those who have recovered.
The preliminary study by authors from New York’s Stanford, Yale, and Mount Sinai, which has yet to be published or peer-reviewed, found that people infected with COVID may frequently suffer similar neurological impacts as people who have undergone a cancer treatment. This is a condition known as cancer therapy-related cognitive impairment (CRCI) or “chemo brain.”
“(The) findings presented here illustrate striking similarities between neuropathophysiology after cancer therapy and after SARS-CoV-2 infection, and shed light on cellular deficits that may contribute to long-lasting neurological symptoms even after infection. mild SARS-CoV-2,” the authors wrote.
The symptoms of COVID-19 and the brain
Using infected mice as a model, the researchers found a “marked decrease” in the generation of new neurons in the hippocampus region of the brain just one week after infection and determined that the condition persisted for at least seven weeks. (Generation of neurons in that brain region is thought to “support healthy memory function,” they noted.)
The researchers examined brain tissue from people who died in early 2020 and were infected with COVID at the time of death, they found “highly elevated” markers of inflammation in the brain, even in those who had only been mildly ill or asymptomatic.
In addition, they studied people suffering from “long-term COVID” into two groups, those with cognitive effects and those without, most of whom had only mild infections and had not been hospitalized. People with cognitive effects had elevated levels of a protein associated with inflammation in their plasma, the authors reported.
Omicron symptoms of COVID-19
“Taken together, the findings presented here underscore profound multicellular dysregulation in the brain caused by even mild respiratory SARS-CoV-2 infection,” the researchers summarized in their discussion.
Much of the data in the study comes from an earlier stage of the pandemic, and the scientists say it’s not yet clear what long-term impact the omicron variant will have, for example, on people.
“The incidence and severity of cognitive impairment after COVID-19 caused by newer variants of SARS-CoV-2, such as the Omicron variant, or as a result of advanced infection in vaccinated individuals remain to be determined,” they scored.
The study adds to a growing body of evidence about what some are calling “COVID brain” or “COVID fog,” which scientists are still trying to fully understand, particularly how long it might last in those who have recovered.