Chronic traumatic encephalopathy in contact sports: The Canadian experience

Abstract

Chronic traumatic encephalopathy (CTE) is suggested to be a progressive neurodegenerative disease, characterized by tau deposits in the depth of cortical sulci in neurons and in glioneuronal complexes around blood vessels. Few studies have suggested that it is caused by multiple concussions or subconcussive brain injuries. A recent publication showed that most American football players whose brain were donated to the Boston University concussion center had CTE (Mez et al. 2017). Over the last 6 years, with the help of neuropathologist colleagues across Canada, we have collected the brains of 33 high level professional and amateur athletes. These include 5 National hockey league (NHL) players, 15 Canadian football league (CFL) players, 3 College football players, 3 College hockey players, 2 professional boxers, 1 professional bull rider, 1 BMX champion, 1 rugby player and 2 skiers. All were male and the ages ranging from 15 to 87 years. Our results indicate that only a small portion of cases have CTE. Moreover, most cases are low stage (stage 1 or 2) and this pathology is mainly seen in some of the younger players. Older players either have no pathological findings or have other neurodegenerative diseases such as Alzheimer’s disease. The disparity of results between the 2 groups will be discussed.