Blood biomarkers show even one-off brain injuries have effects lasting decades

Monash University-led research, believed to be the first of its kind, has used blood tests and MRI scans to show that the effects of traumatic brain injuries (TBI) can last decades.

Published in Brain, and involving researchers from the University of Melbourne and Austin Health, the Monash-Epworth Rehabilitation Research Center (MERRC) TBI Aging Study integrated a range of techniques to understand the enduring consequences of moderate to severe TBI.

The team included imaging to measure the integrity of the brain microstructure, blood biomarkers to determine ongoing brain pathology, and cognitive tests to understand how blood markers might be linked to a person’s cognitive health and clinical condition.

It’s one of few global studies on participants with moderate-severe TBI due to a single incident that have also been living with their injury for an average of 22 years, as opposed to experiencing repetitive injury.

Senior author Professor Sandy Shultz, from the Monash School of Translational Medicine, said, “Our finding of chronic pathology in the brains of traumatic brain injury survivors, and the ability to identify this with imaging and blood tests, not only provides us with methods to detect these changes but also a foundation to develop treatments that might prevent or slow evolving pathology and improve recovery.”

While TBI is a potential risk factor for neurodegenerative disorders, including Alzheimer’s Disease and Parkinson’s Disease, there is a critical need for comprehensive knowledge about long-term impacts.

This involves delineating the biological and clinical characteristics of any lasting neurodegeneration and identifying who is at risk, and then using this information to develop long-term management strategies.

First author Dr. Gershon Spitz, from the Monash-Epworth Rehabilitation Research Center (MERRC), the Monash School of Psychological Sciences, and the School of Translational Medicine Department of Neuroscience, said the findings supported the hypothesis that the effects of a moderate-severe TBI could be felt decades following the initial injury.

“We found that elevated levels of blood biomarkers are related to poorer brain microstructure and poor cognition,” Dr. Spitz said.

“Traditionally, TBI was viewed as an isolated event with a fixed recovery trajectory. Over the last decade, TBI has been redefined as a chronic, ongoing health condition.

“This redefinition is a crucial first step in overhauling our health care models, which presently allocate the bulk of resources to the immediate post-injury phase and leave long-term symptoms inadequately treated.”

Dr. Spitz said further work was needed on the connection between blood biomarkers and symptoms/improvement. “We need to see whether the biological signatures of possible ongoing neuropathology can also tell us about people who may be at higher risk of experiencing progressive decline in functions like memory,” he said.