Researchers might have already found an answer to questions about the lingering cognitive issues in long COVID patients.

Scientists said in a study published last Friday that an overstimulated immune system could be the one responsible for the brain fog and all other cognitive problems post-COVID syndrome patients are experiencing, ABC News reported Tuesday.

The Role Of Inflammation

When the immune system is overstimulated, persistent cognitive problems could occur. The overstimulation is believed to be triggered by the ongoing vascular injury and repair caused by the changes and inflammation that the COVID-19 infection brought with it.

The research team found an “inflammatory signature” in the cerebrospinal fluid of the 13 study participants who still had lingering cognitive problems 10 months after battling the novel coronavirus.

The levels of the two inflammatory markers in the spinal fluid were higher in patients experiencing persistent cognitive issues after their bout with mild COVID-19. The levels were lower in patients without symptoms during the infective stage of the disease.

Aside from the C-reactive protein and serum amyloid A inflammatory markers in the spinal fluid, researchers also noticed a spike in the vascular endothelial growth factor markers, suggesting that there was healing and repair in response to the inflammation.

“Many millions of people experience persistent cognitive issues after SARS-CoV-2 infection, which can impact even young, healthy adults who had a mild case of COVID,” lead researcher Dr. Joanna Hellmuth, of the University of California, San Francisco, said.

“However, there are not yet effective laboratory tests or treatments for COVID-associated cognitive changes, in part, because we do not understand the underlying biology,” she continued.

Implications Of The Study

Unfortunately, the study they conducted was very small. Hellmuth acknowledged this in an interview with MedPage Today. But if the findings were true, the team’s research could help establish what needs to be done to address the lingering cognitive issues brought about by COVID-19.

“This is an important observation. It suggests vascular injury and repair in the brain may set up the inflammation,” said Dr. Avindra Nath, the clinical director of the National Institute of Neurological Disorders and Stroke at the National Institutes of Health, who was not part of the study.

Nath suggested that a clinical trial could help move treatment forward while shedding light on what is causing the post-COVID symptoms affecting the brain.

He added that now is the perfect time to move forward with trials and studies focusing on the post-COVID cognitive problems because billions of people could be affected.

“People say you need to know the mechanism behind this," Nath said. "And I would say, yes, that's absolutely true: you don't want to rush because you don't want to cause harm. But ... [y]ou’ve got billions of people infected. It takes years to figure out mechanisms. Can we really afford to wait that long?” Nath said.

The preliminary work of Hellmuth’s team was presented at the American Academy of Neurology annual meeting over the weekend.