This study delves into the significant advancements in the scientific understanding of CTE over the past 17 years. The article discusses the history of CTE, originally known as “punch-drunk” syndrome in boxers, and its progression to a recognized neuropathological condition. It outlines the development of diagnostic criteria for CTE by consensus conferences convened by the National Institute of Neurological Disorders and Stroke (NINDS) and National Institute of Biomedical Imaging and Bioengineering (NIBIB), emphasizing the unique pathology characterized by perivascular accumulation of phosphorylated tau protein (p-tau) in the brain.
The article reviews the evolution of neuropathological criteria for CTE diagnosis, from early case reports to the establishment of the NINDS–NIBIB criteria. It also discusses the relationship between repetitive head impacts (RHI) and CTE, highlighting a robust dose-response relationship with years of American football play and the likelihood of a causal relationship between RHI and CTE. The article stresses that CTE can currently only be definitively diagnosed postmortem and that the corresponding clinical condition is known as traumatic encephalopathy syndrome (TES).
Three thought-provoking points from the article are:
The Unique Pathology of CTE: The article describes the distinct molecular structure of p-tau fibrils in CTE, which differs from other tauopathies and neurodegenerative diseases like Alzheimer’s. This suggests that CTE has a unique pathogenesis linked to mechanical brain injury.
Diagnostic Challenges: Since CTE can only be diagnosed definitively after death, this presents challenges for living athletes and military personnel who may be suffering from the condition. It raises the question of how to effectively diagnose and treat individuals at risk or showing symptoms of TES during their lifetime.
Prevalence and Exposure: The article notes that over 97% of published CTE cases had known exposure to RHI, predominantly through contact sports. This underscores the potential public health implications for athletes in contact sports and the need for preventive measures and safer protocols.
