Long Covid Patients Show Brain Changes Associated With Alzheimer's Disease
A groundbreaking study from New York City has revealed that the approximately 20 million Americans suffering from long Covid may face an increased risk of developing dementia, particularly Alzheimer's disease. Long Covid, defined as a chronic condition persisting for at least three months following a Covid-19 infection, presents with a constellation of often debilitating symptoms including severe fatigue, brain fog, shortness of breath, and persistent pain.
Brain Barrier Damage Discovered in Long Covid Patients
Despite recent surveys indicating that eight percent of US adults are living with long Covid, the condition remains poorly understood, prompting researchers to urgently investigate its long-term consequences. The new study, published in the journal Alzheimer's and Dementia, examined 86 individuals with long Covid, comparing them to 67 adults who had recovered normally from Covid and 26 healthy controls who had never contracted the virus.
Using advanced blood tests and MRI scans, the research team discovered that patients with long Covid exhibited a choroid plexus approximately 10 percent larger than healthy individuals. The choroid plexus is a critical network of blood vessels lined by cells responsible for producing cerebrospinal fluid, which removes waste and provides immune support for the nervous system.
Alzheimer's Biomarkers and Cognitive Performance Links
Dr. Yulin Ge, senior study author and professor in the Department of Radiology at NYU Grossman School of Medicine, explained the significance of these findings. "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," Dr. Ge stated.
The research revealed several concerning connections:
- Blood tests showed long Covid patients had elevated levels of proteins associated with Alzheimer's disease progression, particularly p-tau217
- Participants with larger choroid plexus volumes performed approximately two percent worse on standard cognitive screening tests
- The team identified what they termed "vascular remodeling" - inflammation that thickens blood vessels in the choroid plexus
Dr. Thomas Wisniewski, senior study author and director of the Center for Cognitive Neurology at NYU Langone Health, emphasized the importance of ongoing research. "Our next step is to follow these patients over time to see if the brain changes we identified can predict who will develop long-term cognitive issues," he said.
Demographic Factors and Future Research Directions
The study population revealed notable demographic differences, with long Covid patients averaging 61 years old compared to 72 years in the other groups. Long Covid patients were also more likely to have higher body mass index measurements, smoke, consume alcohol, and be diagnosed with high blood pressure and diabetes.
These findings arrive at a critical time, as approximately 7 million Americans aged 65 and older currently live with Alzheimer's disease, with projections suggesting this number could nearly double by 2050. The research team proposes that inflammation caused by long Covid may hinder proper blood flow in the brain, reducing cerebrospinal fluid production and leading to dangerous waste buildup.
"Physical, molecular, and clinical evidence suggests that a larger choroid plexus may be an early warning sign of future Alzheimer's-like cognitive decline," Dr. Ge noted, highlighting the potential for these findings to serve as predictive markers.
The researchers acknowledge that a larger, long-term study will be necessary to determine whether choroid plexus alterations represent a cause or consequence of neurological symptoms. Such research promises to better focus treatment design efforts for the millions affected by long Covid and its potential cognitive consequences.
