A new study from Lund University suggests that traumatic brain injury (TBI) may contribute to Alzheimer’s disease by altering small blood vessels in the brain. The research, published in Acta Neuropathologica, reveals that brain trauma leads to the buildup of amyloid beta, a protein strongly linked to Alzheimer’s.
These findings challenge the long-held belief that neurodegenerative diseases start with nerve cell damage, instead pointing to blood vessel dysfunction as an early trigger.
How Brain Trauma Affects the Brain’s Blood Vessels
It has been known for nearly a century that people with a history of TBI are at higher risk of developing dementia. However, scientists have struggled to understand why. This study, led by Professor Niklas Marklund and Dr. Ilknur Özen, focuses on the role of small blood vessels in the brain.
Brain trauma often reduces blood flow, likely due to damage in vascular smooth muscle cells that regulate blood circulation in the brain. These impairments can cause secondary injuries, worsening brain damage over time.
To investigate, researchers analyzed brain tissue samples from 15 patients who underwent surgery within a week of suffering traumatic brain injuries. They discovered that vascular smooth muscle cells were damaged, and this damage coincided with the buildup of amyloid beta, even in young patients.
A Shift in Understanding: Blood Vessel Damage Before Neuron Loss
Dr. Özen was surprised by how early these changes occurred. “Even in young patients, we saw amyloid beta accumulation along with vascular alterations caused by brain trauma,” she explained. “This suggests that blood vessel damage may be more important in neurodegeneration than previously thought.”
Professor Marklund added, “Our findings challenge the current view of neurodegenerative diseases. Instead of being a consequence of nerve cell damage, blood vessel dysfunction may be an early trigger that speeds up Alzheimer’s-related changes.”
Could Brain Trauma Accelerate Alzheimer’s Disease?
Aging naturally affects blood vessel function, but brain trauma may speed up these processes, potentially increasing Alzheimer’s risk even in younger individuals. However, not everyone who experiences brain trauma develops Alzheimer’s, suggesting that other factors, such as genetics or lifestyle, also play a role.
Hope for Future Treatments
Understanding how brain trauma affects blood vessels at the molecular level could lead to new treatments. If vascular dysfunction is a key driver of neurodegeneration, then therapies aimed at protecting or repairing blood vessels might slow down or prevent Alzheimer’s in people with a history of TBI.
“We are not there yet,” said Marklund, “but this research brings us closer to developing new treatments that target blood vessel health to reduce the risk of dementia after brain trauma.”
This study highlights the urgent need for more research into the brain’s vascular system, especially in relation to traumatic injuries and long-term cognitive decline.
If you care about Alzheimer’s, please read studies about the likely cause of Alzheimer’s disease, and new non-drug treatment that could help prevent Alzheimer’s.
For more information about brain health, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
The research findings can be found in Acta Neuropathologica.
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