While COVID-19 is mostly a respiratory illness, scientists have known for years it can also cause problems in other parts of the body, including the brain. A study from the United Kingdom now shows that brain damage may even keep happening months after infection.
Researchers found that some recovering COVID-19 patients still had blood markers that show ongoing brain injury while they registered as healthy on routine blood inflammation tests, a study published in the journal Nature Communications said.
Researchers examined 800 patients hospitalized with COVID in England and Wales, half of whom had new neurological conditions, according to a news release from the research team. The researchers measured their brain injury markers, serum inflammatory proteins, antibodies, and brain injury proteins.
While patients were COVID-positive, when symptoms came on quickly, they had higher production of inflammatory proteins and brain injury blood markers, the release said. Researchers were surprised to find blood markers that showed ongoing brain injury months after the people in the study were discharged from the hospital, even when testing showed no inflammation. This happened most often in those who had shown new neurological conditions in the acute phase.
“Our study shows that markers of brain injury are present in the blood months after COVID-19, and particularly in those who have had a COVID-19-induced brain complication (e.g. inflammation, or stroke), despite resolution of the inflammatory response in the blood,” principal investigator Benedict Michael, PhD, director of the University of Liverpool’s Infection Neuroscience Laboratory, said in the release.
“This suggests the possibility of ongoing inflammation and injury inside the brain itself which may not be detected by blood tests for inflammation.”