Repetitive head injuries that occur during contact sports and military service may accelerate the aging process by increasing the build-up of beta-amyloid in the brain, leading to worse disease and an increased likelihood of developing dementia. In particular, boxers fared the worst among athletes and military veterans with a history of head injuries. These findings, which currently appear online in the journal Acta Neuropathologica, is the first to establish the age-dependent deposition of beta-amyloid in chronic traumatic encephalopathy (CTE), and may lead to the development of diagnostic tools and treatments for the long lasting effects of head trauma.
Researchers examined a large group of deceased athletes and military veterans with pathologically diagnosed CTE. They compared the number of individuals who developed clumps or deposits of beta-amyloid in the brain in this CTE group to a published group of normal individuals ages 1 to 100. They found that athletes and military veterans with CTE were four times more likely to develop beta-amyloid deposits in their brains and that in general this occurred 10-15 years earlier than in the normal aging group. In addition, researchers looked within the group of athletes and compared those subjects with beta-amyloid to those without. They found individuals with beta-amyloid deposits had worse disease and a worse decline in their thinking ability. In addition, individuals with beta-amyloid were more likely to have Parkinson-like pathology and symptoms.