Long COVID-19 Linked to Alzheimer ’s-Like Brain Changes, New Study Warns of Cognitive Decline Risk

The effects of long COVID-19 are still coming out. More than 20 million Americans are believed to have the debilitating post-infection condition, with symptoms like severe fatigue, shortness of breath, chest pain, palpitations, dizziness, and muscle pain. Now, a new study from NYU Langone Health has explained why a few patients experience incessant “brain fog” and memory issues long after a COVID-19 infection. According to researchers, long COVID-19 triggers changes in your brain that resemble the biological processes seen in diseases like Alzheimer’s disease. “Our work suggests that long-term immune reactions caused in some cases after an initial COVID infection may come with swelling that damages a critical brain barrier in the choroid plexus,”

said Dr. Tulin Ge, senior study author.

How does long COVID-19 affect your brain?

The study, published in the journal Alzheimer’s and Dementia, found that choroid plexus - a network of blood vessels in the ventricles of the brain that produces cerebrospinal fluid, cushions your brain and spinal cord from injury, clears waste, and transports essential nutrients. “Physical, molecular, and clinical evidence suggests that a larger CP may be an early warning sign of future Alzheimer’s-like cognitive decline,” added Ge, who is also a professor in the department of radiology at NYU Grossman School of Medicine. The scientists followed around 85 patients who had neurological symptoms of long COVID-19, 67 of those who fully recovered from the virus without lasting symptoms, and 26 healthy individuals who had never been infected. They found that participants with long COVID-19 had a 10 per cent larger CP compared with those who recovered from the infection without long-term symptoms.Also read: Frequent Vomiting Due To Stress Or Anxiety: How It Happens

What was the reason behind cognitive decline?

Researchers say that while it may seem like a larger CP would be good, it is a key marker of chronic neuroinflammation and neurodegeneration. It is also linked to blood-based biomarkers of Alzheimer’s progression, including phosphorylated tau – pTau217 and glial fibrillary acidic protein, which rises after traumatic brain injury and stroke. Participants with larger CPs performed around 2 per cent worse on a 30-point cognitive test. According to studies, COVID-19 can damage the CP, as similar CP changes have also been seen in infections like viral meningitis and HIV. The team of scientists also proposed that long COVID-19 causes chronic inflammation that thickens blood vessels in the CP. “It is currently unknown whether these changes are reversible. We are actively analysing their follow-up data to address this question,” Ge said in an interview with the New York Post.

What's next in dementia research?

According to the scientists, they would now follow the patients over time to see if the brain changes predict who will develop long-term cognitive issues. They say it will help clarify if the CP alterations are a cause or a consequence of the neurological symptoms, which promises to better focus treatment-design efforts.