Chronic traumatic encephalopathy in sport: a systematic review

Abstract

ObjectiveTo provide a critical review of chronic traumatic encephalopathy (CTE) by considering the range of clinical presentations, neuropathology and the strength of evidence for CTE as a distinct syndrome.Data sourcesSeven electronic databases were searched using a combination of MeSH terms and key words to identify relevant articles.Review methodsSpecific inclusion and exclusion criteria were used to select studies for review. Data extracted where present included study population, exposure/outcome measures, clinical data, neurological examination findings, cognitive assessment, investigation results and neuropathology results.ResultsThe data from 158 published case studies were reviewed. Critical differences between the older descriptions of CTE (the ‘classic’ syndrome) and the recent descriptions (the ‘modern’ syndrome) exist in the age of onset, natural history, clinical features, pathological findings and diagnostic criteria, which suggests that modern CTE is a different syndrome. The methodology of the current studies does not allow determination of aetiology or risk factors.ConclusionsThe clinicopathological differences between the ‘classic’ CTE syndrome and the ‘modern’ syndrome suggest that the new syndrome needs a different nomenclature. Further research is required to clearly define the clinical phenotype of the modern CTE syndrome and establish the underlying aetiology. Future research needs to address these issues through large-scale, prospective clinicopathological studies.

Tackling in Youth Football

“…Whether the pathologic findings are solely attributable to the blows to the head and whether the pathologic changes are significantly associated with the neurobehavioral correlates is debated because these hypotheses remain to be tested by case-control and cohort studies. [50][51][52][53][54] Some have argued that these effects may be attributable to confounding variables, such the use of drugs, alcohol, or performance-enhancing substances. It should be noted, however, that animal models of repetitive concussive brain injury have shown a decrease in cognitive function in the absence of such potential confounding variables.…”

Social norms theory and concussion education

“…Even if the acute post-injury symptoms resolve there may be risk of harm later in life. Evidence among retired professional and college football players finds that the risk of depression, Alzheimer's disease, and other neurodegenerative conditions such as Chronic Traumatic Encephalopathy increases with the number of concussions sustained during the athlete's playing career [15][16][17][18].…”

Evaluating the Risks and Benefits of Participation in High-School Football

“…This condition has become known as chronic traumatic encephalopathy. Although the evidence consists mostly of case reports and series at this time, and there are no definitive studies that show a direct association between the pathologic changes and the presumed neurobehavioral sequelae [25][26][27], the preliminary evidence is compelling. Therefore, Jesse's mom is right to view this as a risk.…”