JACKSONVILLE, Fla. — The long-term effects of a professional fighter battling in the ring are much more serious than the visible broken nose or black eye that lasts a couple of weeks. According to a new study, boxers and mixed martial arts (MMA) fighters may have signs of long-term brain injury in their blood.

Researchers studied blood samples that measured two biological markers of brain injury: neurofilament light chain (NFL) and tau. Both of these elements of nerve fibers can be detected in the blood when the fibers are injured.

Mixed martial arts (MMA) fighters
According to a new study, boxers and mixed martial arts (MMA) fighters may have signs of long-term brain injury in their blood.

“This study is part of a larger study to detect not just individual concussions but permanent brain injury overall at its earliest stages and to determine which fighters are at greatest risk of long-term complications,” says study author, Dr. Charles Bernick of the Cleveland Clinic Lou Ruvo Brain Health Center, in a press release. “Our study looked at data over a five-year period and found elevated levels of two brain injury markers in the blood; now the question is whether they may signify permanent traumatic brain injury with long-term consequences.”

For the study, researchers drew blood samples from 291 active professional fighters (128 boxers and 163 MMA), 44 retired fighters with an average age of 45 (38 boxers, 6 MMA) and 103 non-fighters with an average age of 30. The blood samples were then tested for both protein levels.

Researchers found that both proteins were higher in active professional fighters than retired fighters or non-fighters. Specifically, they found that levels of NFL were 40 percent higher in active boxers than in non-fighters. The NFL levels were also higher depending on how much fighting the participants took part in before the blood test, but also did not increase significantly during the study period. Those fighters with a higher NFL did worse on computerized tests designed to measure the brain’s processing speed.

However, there was a group of fighters who showed increasing levels of tau over time, which affected their brain size. Researchers found that there was a 7 percent decline in the volume of their thalamus — which is responsible for regulating sleep, consciousness, alertness, cognitive function and language and sending sensory an movement signals to other parts of the brain.

“Our study found that higher levels of both proteins may be associated with repetitive head trauma,” says Bernick. “However, neurofilament light may be more sensitive to acute traumatic brain injury whereas tau may be a better measurement of cumulative damage over time. More research needs to be done to see how these may be used to monitor traumatic brain injury and the neurological consequences over time.”

As reported by WebMD, Luke Griggs, the Director of Communications at Headway (the brain injury association) responded to the findings. “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.”

The consequence of brain damage has been thrown around a lot in the sports industry as of late, although it doesn’t stop some some from chasing the thrill of the match. Recently, the NFL has frowned upon because of the study that found brain damage was present in 110 out of 111 brains of deceased NFL players.

The findings were presented at American Academy of Neurology’s Sports Concussion Conference in Jacksonville, Fla., July 14 to 16, 2017.

About Sarah Hockel

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