CTE identified in brains of young athletes

Key takeaways:

• A case study examined 152 brains of young donors who participated in contact sports.
• CTE was diagnosed in 63 of the donors; cognitive and neurobehavioral symptoms were common among all donors.

Young brain donors exposed to repetitive head impacts through contact sports displayed cognitive and neurobehavioral symptoms with or without a diagnosis of chronic traumatic encephalopathy, according to research from JAMA Neurology.

“Repetitive head impacts can result in symptomatic concussions and the much more frequent, nonconcussive injuries that are asymptomatic,” Ann C. McKee, MD, a professor of neurology in the department of neurology at Chobanian and Avedisian School of Medicine at Boston University, and colleagues wrote. “Multiple studies link a longer duration of RHI exposure in U.S. football players with increased odds for the presence of [chronic traumatic encephalopathy] and increased severity of CTE.”

McKee and colleagues sought to characterize the neuropathologic and clinical symptoms of young brain donors who participated in a broad range of contact sports.

Their case series included findings from 152 of 156 donors of athletes (mean age, 22.97 years; 92.8% male), identified through the Understanding Neurologic Injury and Traumatic Encephalopathy (UNITE) Brain Bank, who donated their brains between February 2008 to September 2022. Neuropathologic evaluations, retrospective clinical assessments and online questionnaires were performed with donor next of kin. Primary outcomes for the study included assessments for microscopic neuropathologic assessment, including diagnosis of CTE, as well as next-of-kin reportage of donor’s athletic history and completion of scales measuring cognitive and functional symptoms, as well as neurobehavioral dysregulation.

The researchers reported that CTE was diagnosed in 63 donors, and among those, 60 donors (95.2%) were diagnosed with either stage I or II CTE. Those with CTE were more likely to be older (mean difference, 3.92 years; 95% CI, 2.74-5.10 years). Of the 63 donors with CTE, 45 (71.4%) were men who participated in sports including American football, ice hockey, soccer, rugby and wrestling, while one woman diagnosed with CTE played collegiate soccer.

McKee and colleagues also found cognitive and neurobehavioral symptoms consistent and frequent among all donors. Suicide was the most common cause of death, followed by unintentional overdose. No differences were found in cause of death or clinical symptoms based on CTE status.

Data additionally showed that, among the 152 donors, 92 played American football as their primary sport, with 48 having CTE and 44 without CTE, while duration of playing career was significantly longer in those who had CTE compared with those who did not (mean difference, 2.81 years; 95% CI, 1.15-4.48 years).

”Young donors exposed to RHIs were highly symptomatic regardless of CTE status, and the causes of symptoms in this sample ... are likely multifactorial and include RHI-and-non-RHI-related causes,” McKee and colleagues wrote.