Histological evidence of chronic traumatic encephalopathy in a large series of neurodegenerative diseases

Excerpt

Chronic traumatic encephalopathy (CTE) is a long-term neurodegenerative consequence of repetitive traumatic brain injury (rTBI). The histological features of CTE are characterised by neurofibrillary tangles (NFTs) composed of both 3-repeat and 4-repeat tau isoforms and astrocytic tau pathology (ATs) commonly in the frontal and temporal cortices and are distinct from other tauopathies [9]. The recent classification delineates 4 pathological stages with progression of tau pathology from multifocal (I and II) to widespread disease (III and IV) [12]. Of 68 CTE cases in the McKee series with history of rTBIs, only 43 had pure CTE pathology, the other 25 cases (37 %) had co-morbid neurodegenerative disorders (NDDs) including Lewy body disease, motor neuron disease, Alzheimer’s disease (AD), frontotemporal lobar degeneration (FTLD), Pick’s disease and progressive supranuclear palsy (PSP) [12]. TDP-43 pathology was found in 85 % of CTE cases across all disease stages [12]. Our group reported an ex-professional boxer with dual pathologies of CTE and PSP [10]. It is possible that rTBIs or the existence of chronic CTE-tau pathology play a role in triggering the deposition of other abnormal proteins in the brain [17, 18]. The existing literature mainly focused on high-risk individuals especially contact sport athletes. This study aimed to investigate the prevalence of histological evidence of CTE in the general population with or without NDDs which is currently not known. …