A new study suggests that Long COVID—the lingering post-infection condition experienced by many people after SARS-CoV-2 infection—might be associated with brain changes resembling those seen in Alzheimer’s disease and other neurodegenerative disorders.
Researchers are increasingly investigating how persistent neurological effects, such as “brain fog,” memory troubles, and cognitive slowing, may reflect deeper structural and biological changes in the brain long after the acute phase of COVID-19 has passed.
What the New Research Found
The study, published in the journal Alzheimer’s & Dementia, focused on a brain structure called the choroid plexus (CP)—a network of tissue involved in producing cerebrospinal fluid and clearing waste from the brain. In people with Long COVID, this structure was found to be enlarged by about 10% compared with individuals who fully recovered from COVID or never had the infection.
Alongside structural enlargement, the researchers observed differences in the blood flow and function of the CP, which are important for maintaining brain health and clearing potentially toxic proteins. The affected individuals also scored slightly lower on standard cognitive tests, indicating subtle but measurable impacts on thinking and memory.
Alzheimer’s-Related Biomarkers in Long COVID
The study also noted elevated levels of biomarkers in Long COVID patients that have been linked to Alzheimer’s disease—such as phosphorylated tau (pTau217) and glial fibrillary acidic protein (GFAP)—suggesting that common biological pathways might be activated in both conditions.
These proteins are typically associated with neurodegeneration and brain injury, and their presence raises questions about whether COVID-related inflammation could contribute to later cognitive decline. However, scientists say it’s too early to conclude that COVID directly causes Alzheimer’s disease.
What This Means for Long COVID Patients
Long COVID has long been linked to persistent neurological symptoms. A global collaboration of researchers found that cognitive impairment following COVID-19 can be more severe and lasting in older adults, and may resemble patterns seen in age-related neurodegeneration.
Other studies support the idea that the coronavirus and the immune response it triggers could disrupt brain function by:
Provoking neuroinflammation that may impair neural health and communication.
Altering brain microstructure and neurochemical profiles, potentially affecting memory and attention.
Changing brain protein levels in ways similar to those found in Alzheimer’s research.
Despite uncertainties, neurologists are increasingly recommending monitoring cognitive function in people recovering from COVID-19, especially those reporting persistent symptoms like brain fog, memory lapses, or difficulty concentrating. Regular neurological checkups and cognitive screenings can help identify changes early and guide supportive care.
As research evolves, understanding the connections between Long COVID and neurological health will be critical—not just for patient care, but for guiding public health responses and rehabilitation strategies in the years ahead.
