Blood test suggests boxers' long-term brain injuries
14th July 2017 -- Boxers and mixed martial arts fighters may have markers of long-term brain injury in their blood, a US medical conference has heard.
Researchers studied blood samples from 291 active professional fighters (128 boxers and 163 mixed martial arts), 44 retired fighters (38 boxers, 6 mixed martial arts), and 103 non-fighters.
They were participants in the larger and ongoing Professional Fighters Brain Health Study.
They measured two blood plasma proteins that are known biological markers of brain injuries:
- Neurofilament light chain (NFL)
To ensure accuracy the laboratory technicians analysing the blood didn’t know which of the groups each sample came from.
In active fighters the protein levels were 40% higher than in non-fighters or retired fighters.
NFL levels, but not tau, were higher depending on how much fighting the participants said they'd done in the fortnight before testing.
The results were not affected by age or ethnic backgrounds. However, those with higher NFL levels also did worse in computer-based tests of brain processing speed.
The researchers say their findings support concentrations of NFL and tau being higher in people exposed to repetitive head trauma.
They say more research is needed to see whether the protein measurements point to any permanent traumatic brain injury and its consequences in the longer-term.
The study received support from some US boxing organisations.
Reacting to the findings in an emailed statement, Luke Griggs, director of communications at Headway, the brain injury association, says: "Every single blow to the head – no matter how hard – can potentially result in lasting damage to the brain. We have known for some time of the risks associated with boxing, indeed 11 medical associations around the world, including the British Medical Association, have said chronic brain damage is caused by repeated blows to the head.
"It is clear that the short-term risks of suffering an acute injury in the ring are compounded by the cumulative effects of repeated blows."
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the 'peer review' process, in which outside experts scrutinise the data prior to publication in a medical journal.