Biomarkers in traumatic brain injury

Traumatic brain injury affects millions of people each year and often results in long-term cognitive, psychiatric, and physical problems. The brain damage, even in comparable cases, varies greatly.

The long-term consequences of traumatic brain injury are often misunderstood, with many patients receiving vague diagnoses like post-concussion syndrome, which may lead to inappropriate management.

A major contributor to these prolonged effects is the development of progressive neurodegenerative conditions, where harmful proteins accumulate in the brain. That condition has some similarities with diseases such as Alzheimer’s and chronic traumatic encephalopathy.

Biomarkers in our blood
Recent research has highlighted the potential of blood tests as a tool for diagnosing and tracking these long-term effects. It is done like in neurodegenerative diseases, such as Alzheimer’s, by measuring low concentrations of brain-derived proteins in the blood.

Studies have shown that certain proteins, such as tau and UCH-L1, remain elevated in the blood long after severe traumatic brain injury, even years later. These proteins correlate with brain damage and cognitive problems, and advanced testing technologies now allow for the precise detection of these biomarkers.

This represents a major leap forward in non-invasive, cost-effective diagnostics. Biomarkers can provide valuable information not only about the presence, but also the progression of the condition.

Just as important, measuring the biomarkers may dismiss the risk of long-term effects of a previous trauma in others.

From brain damage to brain degeneration
The role of blood biomarkers is important in understanding if traumatic brain injury might accelerate neurodegenerative diseases. For example, blood levels of tau suggest that brain damage from traumatic brain injury may lead to early amyloid and tau buildup, potentially speeding up the development of Alzheimer's disease.

Moreover, biomarkers like UCH-L1 may indicate persistent disruptions in protein homeostasis after the injury, which could be linked to the development of neurodegeneration.

As this research progresses, blood tests may become an essential part of assessing the impact of traumatic brain injury, particularly in older adults who are at higher risk of neurodegenerative conditions.

This could lead to more accurate diagnoses, better prognostication, and earlier interventions to prevent further neurological decline.

About the scientific paper:

First author: David Sharp, England
Published: Brain, November 2024.
Link to paper: https://academic.oup.com/brain/article/147/11/3641/7866920?searchresult=1