• Posted June 29, 2023

New Ways to Spot Risk for CTE in Boxers, MMA Fighters

Autopsy is currently the only way to definitively diagnose chronic traumatic encephalopathy (CTE), a degenerative brain disease often seen in athletes who've suffered repeated blows to the head.

But there may be a way to predict which athletes are likely to develop CTE, researchers report June 28 in the journal Neurology.

They outline criteria for a condition called traumatic encephalopathy syndrome, where CTE is suspected based on cognitive impairment, behavior changes and other factors.

“These findings suggest that this new diagnosis of traumatic encephalopathy syndrome may be useful in professional sports such as boxing and mixed martial arts and may be helpful in predicting who may experience cognitive decline,” study co-author Brooke Conway Kleven said in a journal news release. She is with the University of Nevada, Las Vegas School of Public Health.

CTE was originally studied in boxers as "punch-drunk syndrome." The progressive and fatal brain disease is linked to the development of dementia.

For the new study, researchers studied 130 active and retired professional fighters in boxing, martial arts and mixed martial arts. They were a part of a brain health study run by the Cleveland Clinic in Ohio.

Participants had brain scans and took cognitive tests when the study began.

Researchers found that those who met the criteria for traumatic encephalopathy syndrome had greater declines in brain volume. These participants also had a faster annual rate of decline in brain volume.

In all, 52 participants, about 40% of the total, met the criteria for traumatic encephalopathy syndrome. More than 80% of them listed boxing as their only form of fighting.

Annual brain scans and cognitive tests were done for up to six years. They showed that an area of the brain that plays a role in memory had volumes that were 385 cubic millimeters smaller in athletes with the syndrome than in those without the syndrome. Researchers also found that those with the syndrome lost volume at an average rate of 41 cubic millimeters per year faster than those without the syndrome.

The study also showed that people with traumatic encephalopathy syndrome had slower reaction times and lower scores on cognitive tests, which involve thinking and memory.

“Our results suggest that the criteria for traumatic encephalopathy syndrome can identify people who are more likely to have worsening brain shrinkage and cognitive issues over time, while those who do not meet the criteria for the syndrome remain relatively stable,” Conway Kleven said. “Further research is needed to validate the accuracy of these criteria in detecting CTE.”

The athletes reported their own information, which could not be verified and was thus a study limitation.

More information

The Alzheimer's Association has more on chronic traumatic encephalopathy.

SOURCE: Neurology, news release, June 28, 2023