Early stage of CTE?
Neuropathological analysis revealed neuronal p-tau aggregates in all CTE cases, a hallmark of the disease.
Young athletes with CTE had significantly more ventricular dilatation, suggesting atrophy or shrinkage of the brain, and more cavum septum pellucidum.
“I was surprised that even at this very young age group we could see structural changes to the gross pathology,” Dr. McKee said.
Investigators also found evidence of perivascular macrophages in the deep white matter, a microscopic change that correlated with CTE and years of play and indicates a breach of the blood-brain barrier that could allow pro-inflammatory molecules to enter the brain, setting up a neuroinflammatory response.
“Neuroinflammation is a very early change after repetitive head impacts, as well as in CTE,” Dr. McKee said. “This may be one of the mechanisms by which the inflammation starts, meaning microvascular injury might be an integral part of the pathogenesis of CTE.”
A message for clinicians
All athletes had symptoms of mood and neurobehavioral dysfunction common in people with RHIs. There were no significant differences in those clinical symptoms based on CTE diagnosis, which is likely related to the retrospective nature of the clinical evaluations, Dr. McKee said.
While the study leaves many questions about CTE in younger athletes unanswered, there is a message for clinicians and for patients in the findings, she said.
For clinicians, it’s important to note that “this young population of amateur athletes can be very symptomatic, and in all likelihood, a lot of these symptoms are reversible with proper care and management,” Dr. McKee said.
“For individual athletes, it’s important to note that 58% of this cohort did not have CTE, so just because you have these symptoms is not an indication that you have a neurodegenerative disease,” she added.
The study was funded by Andlinger Foundation, the National Football League, Mac Parkman Foundation, National Operating Committee on Standards for Athletic Equipment, and the Nick and Lynn Buoniconti Foundation, World Wrestling Entertainment, Alzheimer’s Association, National Institutes of Health, Concussion Legacy Foundation, U.S. Department of Defense and the U.S. Department of Veterans Affairs. Dr. McKee is a member of the Mackey-White Health and Safety Committee of the National Football League Players Association and reported receiving grants from the NIH and Department of Veteran Affairs and other funding from the Buoniconti Foundation and Mac Parkman Foundation during the conduct of the study.
A version of this article appeared on Medscape.com.