A new study led by Prof David Sharp, Centre Director at UK DRI Care Research & Technology, has used a state-of-the-art blood test to track damage to the brain in people who have sustained traumatic brain injury (TBI). Measuring the protein biomarker in the blood will provide a simpler, more accurate way to predict clinical outcomes and may help to identify those at higher risk of developing dementia. The study is published today (29 September) in Science Translational Medicine.
Around 50 million people each year worldwide experience TBI as a result of head injury. In the brains of these individuals, the neurons encounter severe stretching and sheering forces which cause damage to their axons, the part which transmits electrical signals. Axonal damage is the best predictor of clinical outcomes and recovery but has been difficult to measure in patients.
The team from the UK DRI Care Research and Technology Centre, based at Imperial College London, set out to identify a chemical that could be easily detected in the blood - a biomarker - that would accurately reflect this axonal damage in the brain after TBI. A multicentre study was established involving over 200 patients who had experienced moderate to severe TBI, recruited from eight major trauma centres across Europe. In 56% of cases the injuries were classed as ‘high energy’, involving falls from over 3 metres or collisions at more than 30km/hour, with the majority of these caused by road traffic accidents.
To find a suitable protein marker, the researchers harnessed cutting-edge technology called single molecule array (SiMoA) that can measure sub-femtomolar (10-16) levels of chemicals in the blood. Starting their search by detecting proteins that are important to the structure of the axons, they found that measuring blood levels of neurofilament light provided a remarkably accurate long-term prognosis for the patient. Neurofilament light has become a useful tool for diagnosis, monitoring and prognosis across neurodegenerative disease like Alzheimer’s, but its potential for use in TBI has not been fully assessed and optimised until now.