Emerging research suggests a potential link between long COVID and the development of Alzheimer’s-like brain changes. While the connection is still being investigated, studies are revealing concerning overlaps in the biological markers and neurological effects observed in both conditions.
Long COVID and Brain Structure Changes
A study led by researchers at NYU Langone Health, published in Alzheimer’s & Dementia, found that patients experiencing long COVID exhibited a 10 percent larger choroid plexus (CP) compared to individuals who had fully recovered from an initial SARS-CoV-2 infection. The CP is a network of blood vessels within the brain responsible for producing cerebrospinal fluid, which cushions the brain and helps remove waste products. It also plays a role in regulating the brain’s immune response.
“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,” explained Dr. Yulin Ge, a professor in the Department of Radiology at NYU Grossman School of Medicine.
Importantly, the increased CP size correlated with elevated levels of specific proteins in the blood, including pTau217, a biomarker associated with Alzheimer’s disease, and Glial fibrillary acidic protein (GFAP), which indicates brain injury. Patients with larger CPs also demonstrated a slight, average 2 percent decrease in performance on the mini–mental state examination (MMSE), a standard test used to assess cognitive function, specifically memory and attention.
Similarities to Alzheimer’s Disease
The findings build on growing evidence of neurological dysfunction following COVID-19 infection. Researchers are noting similarities between the brain changes seen in long COVID and those characteristic of Alzheimer’s disease and related dementias. One study highlighted that the slowing and abnormality of intrinsic brain activity in COVID-19 patients resemble those seen in Alzheimer’s and related dementias.
The study from NYU Langone suggests that damage to the CP, potentially caused by the initial COVID-19 infection, could disrupt the brain’s waste clearance systems and contribute to inflammation, creating an environment conducive to the development of Alzheimer’s-like pathology. The virus itself has been shown to damage the cells lining the CP blood vessels.
Distinguishing Long COVID from Flu: Brain Effects
Research also indicates that the long-term neurological effects of COVID-19 differ from those of influenza. While both illnesses can cause cognitive symptoms, the nature and duration of these effects appear to be distinct. The specific differences are still being investigated, but the data suggest that COVID-19 may have a more pronounced and persistent impact on brain function.
Brain Fog and Cognitive Impairment
A significant number of individuals with long COVID report experiencing “brain fog,” characterized by difficulties with concentration, memory, and executive function. Studies suggest that Americans report experiencing brain fog at a higher rate than individuals in other parts of the world, potentially due to differences in healthcare access, lifestyle factors, or viral variants.
Long-term neurological dysfunction associated with COVID-19 includes not only cognitive impairment but also fatigue, depression, and anxiety. These symptoms can significantly impact quality of life and daily functioning.
What Does This Mean for the Future?
While these findings are concerning, it’s crucial to emphasize that they do not mean everyone who has long COVID will develop Alzheimer’s disease. The research is still in its early stages, and more studies are needed to fully understand the long-term neurological consequences of COVID-19.
The increased CP size observed in long COVID patients may serve as an early warning sign for potential cognitive decline, allowing for earlier intervention and monitoring. However, further research is needed to determine the clinical significance of this finding and to identify individuals at highest risk.
Currently, there is no specific treatment to reverse the brain changes observed in long COVID. Management focuses on addressing individual symptoms and providing supportive care. Ongoing research is exploring potential therapeutic strategies to mitigate the neurological effects of long COVID and prevent long-term cognitive decline.
The connection between long COVID and Alzheimer’s-like changes underscores the importance of continued research into the long-term health consequences of COVID-19 and the development of effective strategies for prevention and treatment. It also highlights the need for comprehensive neurological assessments for individuals experiencing persistent symptoms following a COVID-19 infection.
