Risk of CTE from young age revealed in new study

The extent of young athletes involved in contact and collision sports who have Chronic Traumatic Encephalopathy (CTE) has been revealed in a new study. 

Research has found that, among a sample of 152 young athletes exposed to repetitive head impacts (RHI) who were under age 30 at the time of death, 41.4 per cent (63) had neuropathological evidence of CTE, a degenerative brain disease which evidence shows is caused by RHI.

The study, by Boston University Chronic Traumatic Encephalopathy (CTE) Center – which is the largest CTE case series ever in youth, high school and college athletes who died young – includes the first American woman athlete diagnosed with CTE, a 28-year-old collegiate soccer player whose identity remains private.

“This study clearly shows that the pathology of CTE starts early,” said corresponding author Dr Ann McKee, chief of neuropathology at VA Boston Healthcare System and director of the BU CTE Center. 

“The fact that over 40 per cent of young contact and collision sport athletes in the UNITE brain bank have CTE is remarkable – considering that studies of community brain banks show that fewer than one per cent of the general population has CTE.”

Nearly all the young athletes had mild CTE, stages one and two; three donors had CTE stage three. (There are four possible stages of CTE with stage four being the most severe). 

In those with CTE, there was often other evidence of brain injury, including the presence of a cavum septum pellucidum, enlargement of the ventricles, and more perivascular macrophages in the white matter.

Clinical symptoms were common among the athletes, whether or not they had CTE. Clinical symptoms included depression (70.0 per cent), apathy (71.3 per cent), difficulty controlling behaviours (56.8 per cent), and problems with decision making (54.5 per cent). Substance abuse also was frequent, with alcohol abuse present in 42.9 per cent and drug abuse in 38.3 per cent.

“The study suggests that some of the symptoms these young athletes are experiencing are not caused by the early tau pathology of CTE,” said Dr McKee. 

“It is imperative that young athletes who are experiencing neuropsychiatric symptoms seek out care, as it is likely that the symptoms can be reduced with effective management and follow-up.”

Amateur athletes comprised 71.4 per cent of those diagnosed with CTE, and included American football, ice hockey, soccer and rugby players, and wrestlers. 

Those diagnosed with CTE were older (average age at death 25.3 years vs. 21.4) and had significantly more years of exposure to contact sports (11.6 vs 8.8 years).

Like all brain bank studies, the brain donors are different from the general population of young athletes, in part because they are more likely to have symptoms. CTE cannot yet be diagnosed in the living, and the true prevalence of CTE in any population remains unknown.

“This study highlights the importance of assessing the symptoms and clinical presentation of CTE in living athletes who have sustained repetitive head injuries,” said Dr Nsini Umoh, program director for traumatic brain injury (TBI) research at the National Institute of Neurological Disorders and Stroke (NINDS), which contributed funding to the study. 

“While additional research in this area is needed, these findings are a notable addition to the body of research on CTE.”

Further needed research includes analysing young brain donors not exposed to contact and collision sports, to better understand non-CTE brain damage from RHI, and what symptoms are related to concussions, RHI, and CTE.