Cited by 1,098Traumatic Brain Injury ResearchLong-Term Effects of COVID-19Automotive and Human Injury Biomechanics

Clinicopathological evaluation of chronic traumatic encephalopathy in players of American football

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Mez, Jesse, Daneshvar, Daniel H., Kiernan, Patrick T., Abdolmohammadi, Bobak, Alvarez, Victor E., Huber, Bertrand R., Alosco, Michael L., Solomon, Todd M. +19 more·2017·JAMA

Abstract

Importance: Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE). Objective: To determine the neuropathological and clinical features of deceased football players with CTE. Design, Setting, and Participants: Case series of 202 football players whose brains were donated for research. Neuropathological evaluations and retrospective telephone clinical assessments (including head trauma history) with informants were performed blinded. Online questionnaires ascertained athletic and military history. Exposures: Participation in American football at any level of play. Main Outcomes and Measures: Neuropathological diagnoses of neurodegenerative diseases, including CTE, based on defined diagnostic criteria; CTE neuropathological severity (stages I to IV or dichotomized into mild [stages I and II] and severe [stages III and IV]); informant-reported athletic history and, for players who died in 2014 or later, clinical presentation, including behavior, mood, and cognitive symptoms and dementia. Results: Among 202 deceased former football players (median age at death, 66 years [interquartile range, 47-76 years]), CTE was neuropathologically diagnosed in 177 players (87%; median age at death, 67 years [interquartile range, 52-77 years]; mean years of football participation, 15.1 [SD, 5.2]), including 0 of 2 pre-high school, 3 of 14 high school (21%), 48 of 53 college (91%), 9 of 14 semiprofessional (64%), 7 of 8 Canadian Football League (88%), and 110 of 111 National Football League (99%) players. Neuropathological severity of CTE was distributed across the highest level of play, with all 3 former high school players having mild pathology and the majority of former college (27 [56%]), semiprofessional (5 [56%]), and professional (101 [86%]) players having severe pathology. Among 27 participants with mild CTE pathology, 26 (96%) had behavioral or mood symptoms or both, 23 (85%) had cognitive symptoms, and 9 (33%) had signs of dementia. Among 84 participants with severe CTE pathology, 75 (89%) had behavioral or mood symptoms or both, 80 (95%) had cognitive symptoms, and 71 (85%) had signs of dementia. Conclusions and Relevance: In a convenience sample of deceased football players who donated their brains for research, a high proportion had neuropathological evidence of CTE, suggesting that CTE may be related to prior participation in football.

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Crossref · 10.1001/jama.2017.8334

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  • The presence of comorbid ALS+CTE in an ALS cohort parallels similar findings of CTE in neurodegenerative cohorts, e.g. 6% in an MSA cohort, 6% in an American football CTE group, and 11.9%-32% in a group of various diseases.

    “The presence of comorbid ALSþCTE in an ALS cohort parallel similar findings of CTE in neurodegenerative cohorts, e.g.6% in an multiple system atrophy (MSA) cohort as reported by Koga et al (46), 6% in an American football CTE group (47) and 11.9%-32% in a group of various diseases reported by Ling et al (48).”

    From Chronic Traumatic Encephalopathy Within an Amyotrophic Lateral Sclerosis Brain Bank Cohort (2018) · cites this paper as [47]

    The Discussion (page not available in our copy) reports comorbid motor neuron disease among football players with severe CTE pathology, supporting the comparison with ALS+CTE. It does not give a 6% figure for that comorbidity, so the specific percentage attributed to this paper is not verified. The MSA and other-disease figures are attributed to separate citations, not this source. (LLM, conf=0.83)

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Authors
Mez, J., Daneshvar, D. H., Kiernan, P. T., Abdolmohammadi, B., Alvarez, V. E., Huber, B. R., Alosco, M. L., Solomon, T. M., Nowinski, C. J., McHale, L., Cormier, K. A., Kubilus, C. A., Martin, B. M., Murphy, L., Baugh, C. M., Montenigro, P. H., Chaisson, C. E., Tripodis, Y., Kowall, N. W., Weuve, J., McClean, M. D., Cantu, R. C., Goldstein, L. E., Katz, D. I., Stern, R. A., Stein, T. D., & McKee, A. C.
Affiliations
  • Boston University (US)
  • Concussion & CTE Foundation (US)
  • Boston Children's Hospital (US)
Corresponding author
McKee, Ann C.
Venue
JAMA
Published
2017-07-25
Volume
318
Issue
4
Pages
360
ISSN
  • 0002-9955 (ISSN-L)
  • 0098-7484
OpenAlex
W2750121529
Cited by
1,098
References
41
Citations by year
2026: 60 · 2025: 78 · 2024: 75 · 2023: 116 · 2022: 137 · 2021: 146 · 2020: 165 · 2019: 139 · 2018: 142 · 2017: 33 · 2016: 1 · 2014: 2
FWCI
102.62
Type
journal article
Language
en
Open access
Licence
other-oa
Locations
  • JAMA (publishedVersion, other-oa)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • OpenBU (Boston University) (submittedVersion)
Funders
  • U.S. Department of Veterans Affairs
  • Alzheimer's Association (NIRG-15-362697)
  • National Operating Committee on Standards for Athletic Equipment
  • National Institute on Aging (K23AG046377, P30AG013846, RF1AG057902)
  • National Institute of Neurological Disorders and Stroke (U01NS086659)
Topics
  • Health Sciences › Medicine › Epidemiology › Traumatic Brain Injury Research
  • Health Sciences › Medicine › Neurology › Long-Term Effects of COVID-19
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Automotive and Human Injury Biomechanics
Keywords
chronic traumatic encephalopathy, American football, neuropathology, neurodegenerative diseases, cognitive symptoms, dementia, head trauma, former athletes, military veterans, concussion
MeSH terms
Chronic Traumatic Encephalopathy, Adult, Aged, Athletic Injuries, Mental Disorders, Brain, Brain Concussion, Cause of Death, Cognition Disorders, Football, Humans, Male, Middle Aged, Severity of Illness Index, United States, tau Proteins, Substance-Related Disorders, Athletes

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