Cited by 176Traumatic Brain Injury ResearchTraumatic Brain Injury and Neurovascular DisturbancesAutomotive and Human Injury Biomechanics

Chronic traumatic encephalopathy in contact sports: A systematic review of all reported pathological cases

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Maroon, Joseph C., Winkelman, Robert, Bost, Jeffrey, Amos, Austin, Mathyssek, Christina, Miele, Vincent·2015·PLoS ONE

Abstract

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with head trauma. Although initially believed to affect only boxers, the at-risk population has expanded to encompass a much wider demographic, including American football players, hockey players, wrestlers, and military veterans. This expansion has garnered considerable media attention and public concern for the potential neurodegenerative effects of head trauma. The main aim of this systematic review is to give a complete overview of the common findings and risk factors for CTE as well as the status quo regarding the incidence and prevalence of CTE. This systematic review was performed using PubMed and MEDLINE and includes all neuropathologically confirmed cases of CTE in the medical literature to date, from the first published case in 1954 to August 1, 2013 (n = 153). The demographics, including the primary source of mTBI (mild Traumatic Brain Injury), age and cause of death, ApoE genotype, and history of substance abuse, when listed, were obtained from each case report. The demographics of American football players found to have CTE are also presented separately in order to highlight the most prevalent group of CTE cases reported in recent years. These 153 case reports of CTE represent the largest collection to date. We found that a history of mTBI was the only risk factor consistently associated with CTE. In addition, we found no relationships between CTE and age of death or abnormal ApoE allele. Suicide and the presence of premorbid dementia was not strongly associated with CTE. We conclude that the incidence of CTE remains unknown due to the lack of large, longitudinal studies. Furthermore, the neuropathological and clinical findings related to CTE overlap with many common neurodegenerative diseases. Our review reveals significant limitations of the current CTE case reporting and questions the widespread existence of CTE in contact sports.

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Authors
Maroon, J. C., Winkelman, R., Bost, J., Amos, A., Mathyssek, C., & Miele, V.
Affiliations
University of Pittsburgh Medical Center (US)
Corresponding author
Bost, Jeffrey
Venue
PLoS ONE
Published
2015-02-11
Volume
10
Issue
2
Pages
e0117338
ISSN
1932-6203 (ISSN-L)
OpenAlex
W2143952936
Cited by
175
References
94
Citations by year
2026: 6 · 2025: 4 · 2024: 8 · 2023: 8 · 2022: 9 · 2021: 13 · 2020: 24 · 2019: 31 · 2018: 18 · 2017: 17 · 2016: 20 · 2015: 16
FWCI
3.08
Type
journal article
Language
en
Open access
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • D-Scholarship@Pitt (University of Pittsburgh) (acceptedVersion)
  • Figshare (submittedVersion, cc-by)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
Mylan
Topics
  • Health Sciences › Medicine › Epidemiology › Traumatic Brain Injury Research
  • Health Sciences › Medicine › Neurology › Traumatic Brain Injury and Neurovascular Disturbances
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Automotive and Human Injury Biomechanics
Keywords
chronic traumatic encephalopathy, contact sports, mild traumatic brain injury, neuropathology, risk factors, APOE genotype, substance abuse, suicide, American football players, military veterans, incidence and prevalence, neurodegenerative diseases
MeSH terms
Brain Injuries, Chronic Disease, Humans, Sports

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