According to new research, prolonged post-COVID cognitive alterations could be the result of an over-stimulated immune system, which could be driven by continuous vascular injury and repair. This early research will be presented at the annual conference of the American Academy of Neurology.

The study suggested that higher levels of two inflammatory markers namely C-reactive protein and serum amyloid A were found in the cerebrospinal fluid of 13 people who had lasting cognitive impairments 10 months after their first COVID symptoms. These participants also had greater levels of vascular endothelial growth factor markers. Despite the small size of the study, the data suggested that inflammation in the brain may play a role in COVID-induced cognitive abnormalities and that COVID infection may cause immunovascular dysregulation via endothelial activation and dysfunction.

Previous research discovered damage in the brain tissue samples of patients who died from COVID due to thinning and leaky blood vessels, but no link was observed between those changes and post-COVID cognition inflammation. Other research indicated that the symptoms of post-COVID cognitive alterations were comparable to those encountered after other viral illnesses such as HIV or Ebola, or after chemotherapy.

In a U.K. Biobank study, 401 COVID patients showed a larger loss of grey matter volume and more brain tissue damage in an average of 4.5 months after infection than persons who had never been infected

Though the exact mechanism causing post-COVID cognitive remains unclear, the studies suggest a presence of persistent immune activation. Brain autopsies inferred the activation of microglia, which is difficult to deactivate once triggered. Hence, the persistent symptoms could be connected to such immunological activation. The National Institutes of Health intends to begin a therapeutic trial of persons with post-COVID cognitive impairments, and their treatment by comparing intravenous high-dose corticosteroids, intravenous immunoglobulin, and placebo.(MedPage Today April 1, 2022)