Doctors figure out potential cause of long-COVID brain fog

By Isobel Williams via SWNS

Post-Covid "brain fog" is down to leaky blood vessels in the brain, according to a new study.

Irish researchers have found that confusion and cognitive decline seen in some patients with long COVID-19 is caused by disruption to blood vessels in the brain.

Long COVID has up to 200 reported symptoms to date, but in general, patients report lingering symptoms such as fatigue, shortness of breath, problems with memory and thinking and joint/muscle pain.

Scientists from Trinity College Dublin note that long COVID has become a major public health issue since the outbreak of the pandemic in 2020.

Of these patients suffering from long COVID, just under 50 percent of them report some form of lingering neurological effect such as cognitive decline, fatigue and brain fog.

The new study, published in the journal Nature Neuroscience, reveals that there was disruption to the integrity of the blood vessels in the brains of patients suffering from long COVID and brain fog.

This blood vessel “leakiness” was able to objectively distinguish those patients with brain fog and cognitive decline compared to patients suffering from long COVID but not with brain fog.

Professor Matthew Campbell said: “For the first time, we have been able to show that leaky blood vessels in the human brain, in tandem with a hyperactive immune system may be the key drivers of brain fog associated with long COVID.

“This is critically important, as understanding the underlying cause of these conditions will allow us to develop targeted therapies for patients in the future.”

The team also uncovered a novel form of MRI scan that shows how long COVID-19 can affect the human brain’s delicate network of blood vessels. 

The researchers hope that their findings will help medical professionals to better care for long COVID patients experiencing these symptoms.

Professor Colin Doherty said: “Undertaking this complicated clinical research study at a time of national crisis and when our hospital system was under severe pressure is a testament to the skill and resource of our medical trainees and staff.

“The findings will now likely change the landscape of how we understand and treat post-viral neurological conditions.”

The scientists note that further research is needed on the subject, and they hope that their findings will not only help with long COVID but other types of viral infection.

First author Dr. Chris Greene added: “Our findings have now set the stage for further studies examining the molecular events that lead to post-viral fatigue and brain fog.

“Without doubt, similar mechanisms are at play across many disparate types of viral infection and we are now tantalizingly close to understanding how and why they cause neurological dysfunction in patients.”