Sports-related concussions — media, science and policy

Journal name:
Nature Reviews Neurology
Volume:
12,
Pages:
486–490
Year published:
DOI:
doi:10.1038/nrneurol.2016.99
Published online

Abstract

Although growing awareness about the potential long-term deleterious effects of sport-related concussion has led to increased attention to the risks of collision sports, calls to ban these sports, such as American football, might be premature. Collision sports have a relatively high incidence of concussions, but participation in these sports also confers a host of benefits. In addition, the associated risks of participation, including concussion, have not been definitively shown to outweigh the benefits they provide, and the risk–benefit ratio might vary among individuals. The risks of concussion and repetitive concussions associated with collision sports are unknown in the general population and not well characterized even in elite athlete populations. In this article, we discuss current knowledge on sports-related concussion, its neurological consequences, and implications for regulation of the practice of collision sports.

At a glance

Figures

  1. From concussion to CTE [mdash] sequence of events and knowledge gaps.
    Figure 1: From concussion to CTE — sequence of events and knowledge gaps.

    Data from clinical case series and animal models suggest that athletes who sustain concussions could develop a form of tauopathy, chronic traumatic encephalopathy (CTE), which leads to the deposition of fibrillary insoluble proteins and progressive deterioration of brain function. A definitive causal link between concussion and CTE has yet to be established, however.

  2. Rates of concussions linked to main collision sports in student athletes.
    Figure 2: Rates of concussions linked to main collision sports in student athletes.

    The rate of concussions (25 sports) and recurrent concussions (17 sports) per 10,000 exposures was measured by the National Collegiate Athletic Association Injury Surveillance Program from 2009–2010 to 2013–2014 in student athletes, during practice and competition. Adapted with permission from SAGE Publications Ltd © Zuckerman, S. L. et al. Am. J. Sports. Med. 43, 26542662 (2015).

References

  1. Meehan, W. P. 3rd & Mannix, R. Pediatric concussions in United States emergency departments in the years 2002 to 2006. J. Pediatr. 157, 889893 (2010).
  2. Daneshvar, D. H., Nowinski, C. J., McKee, A. C. & Cantu, R. C. The epidemiology of sport-related concussion. Clin. Sports Med. 30, 117 (2011).
  3. Omalu, B. Don't let kids play football. New York Times (New York City) (7 Dec 2015).
  4. Bissinger, B. Why college football should be banned. The Wall Street Journal (New York City) (8 May 2012).
  5. McKee, A. C. et al. Chronic traumatic encephalopathy in athletes: progressive tauopathy after repetitive head injury. J. Neuropathol. Exp. Neurol. 68, 709735 (2009).
  6. McKee, A. C. et al. The spectrum of disease in chronic traumatic encephalopathy. Brain 136, 4364 (2013).
  7. Stern, R. A. et al. Long-term consequences of repetitive brain trauma: chronic traumatic encephalopathy. PM R 3, S460S467 (2011).
  8. Kane, M. J. et al. A mouse model of human repetitive mild traumatic brain injury. J. Neurosci. Methods 203, 4149 (2012).
  9. Kondo, A. et al. Antibody against early driver of neurodegeneration cis P-tau blocks brain injury and tauopathy. Nature 523, 431436 (2015).
  10. Ojo, J. O. et al. Repetitive mild traumatic brain injury augments tau pathology and glial activation in aged hTau mice. J. Neuropathol. Exp. Neurol. 72, 137151 (2013).
  11. Omalu, B. I. et al. Chronic traumatic encephalopathy in a national football league player: part II. Neurosurgery 59, 10861092; discussion 10921093 (2006).
  12. Omalu, B. I. et al. Chronic traumatic encephalopathy in a National Football League player. Neurosurgery 57, 128134; discussion 128134 (2005).
  13. Giza, C. C. et al. Summary of evidence-based guideline update: evaluation and management of concussion in sports: report of the Guideline Development Subcommittee of the American Academy of Neurology. Neurology 80, 22502257 (2013).
  14. McCrory, P. et al. Consensus statement on concussion in sport: the 4th International Conference on Concussion in Sport held in Zurich, November 2012. Br. J. Sports Med. 47, 250258 (2013).
  15. Losoi, H. et al. Recovery from mild traumatic brain injury in previously healthy adults. J. Neurotrauma 33, 766776 (2016).
  16. Zemek, R. et al. Clinical risk score for persistent postconcussion symptoms among children with acute concussion in the ED. JAMA 315, 10141025 (2016).
  17. Guskiewicz, K. M. et al. Recurrent concussion and risk of depression in retired professional football players. Med. Sci. Sports Exerc. 39, 903909 (2007).
  18. Guskiewicz, K. M. et al. Cumulative effects associated with recurrent concussion in collegiate football players: the NCAA Concussion Study. JAMA 290, 25492555 (2003).
  19. Collins, M. W. et al. Relationship between concussion and neuropsychological performance in college football players. JAMA 282, 964970 (1999).
  20. Jordan, S. E., Green, G. A., Galanty, H. L., Mandelbaum, B. R. & Jabour, B. A. Acute and chronic brain injury in United States National Team soccer players. Am. J. Sports Med. 24, 205210 (1996).
  21. Tysvaer, A. T. & Lochen, E. A. Soccer injuries to the brain. A neuropsychologic study of former soccer players. Am. J. Sports Med. 19, 5660 (1991).
  22. De Beaumont, L., Lassonde, M., Leclerc, S. & Theoret, H. Long-term and cumulative effects of sports concussion on motor cortex inhibition. Neurosurgery 61, 329336; discussion 336337 (2007).
  23. De Beaumont, L. et al. Brain function decline in healthy retired athletes who sustained their last sports concussion in early adulthood. Brain 132, 695708 (2009).
  24. Tremblay, S. et al. Multimodal assessment of primary motor cortex integrity following sport concussion in asymptomatic athletes. Clin. Neurophysiol. 125, 13711379 (2014).
  25. Tremblay, S. et al. Sports concussions and aging: a neuroimaging investigation. Cereb. Cortex 23, 11591166 (2013).
  26. Tremblay, S., de Beaumont, L., Lassonde, M. & Theoret, H. Evidence for the specificity of intracortical inhibitory dysfunction in asymptomatic concussed athletes. J. Neurotrauma 28, 493502 (2011).
  27. Tremblay, S. et al. Diffuse white matter tract abnormalities in clinically normal ageing retired athletes with a history of sports-related concussions. Brain 137, 29973011 (2014).
  28. Maddocks, D. L. & Saling, M. M. Is cerebral concussion a transient phenomenon? Med. J. Aust. 162, 167 (1995).
  29. Brooks, B. L. et al. Subjective, but not objective, lingering effects of multiple past concussions in adolescents. J. Neurotrauma 30, 14691475 (2013).
  30. Iverson, G. L., Brooks, B. L., Lovell, M. R. & Collins, M. W. No cumulative effects for one or two previous concussions. Br. J. Sports Med. 40, 7275 (2006).
  31. Martland, H. Punch drunk. JAMA 91, 11031107 (1928).
  32. Corsellis, J. A., Bruton, C. J. & Freeman-Browne, D. The aftermath of boxing. Psychol. Med. 3, 270303 (1973).
  33. Stein, T. D., Alvarez, V. E. & McKee, A. C. Concussion in chronic traumatic encephalopathy. Curr. Pain Headache Rep. 19, 47 (2015).
  34. Talavage, T. M. et al. Functionally-detected cognitive impairment in high school football players without clinically-diagnosed concussion. J. Neurotrauma 31, 327338 (2014).
  35. Davenport, E. M. et al. Abnormal white matter integrity related to head impact exposure in a season of high school varsity football. J. Neurotrauma 31, 16171624 (2014).
  36. Koerte, I. K., Ertl-Wagner, B., Reiser, M., Zafonte, R. & Shenton, M. E. White matter integrity in the brains of professional soccer players without a symptomatic concussion. JAMA 308, 18591861 (2012).
  37. Puvenna, V. et al. Is phosphorylated tau unique to chronic traumatic encephalopathy? Phosphorylated tau in epileptic brain and chronic traumatic encephalopathy. Brain Res. 1630, 225240 (2016).
  38. Zuckerman, S. L. et al. Epidemiology of sports-related concussion in NCAA athletes from 2009–2010 to 2013–2014: incidence, recurrence, and mechanisms. Am. J. Sports Med. 43, 26542662 (2015).
  39. Nilsson, M., Hagglund, M., Ekstrand, J. & Walden, M. Head and neck injuries in professional soccer. Clin. J. Sport Med. 23, 255260 (2013).
  40. Finch, C. F., Clapperton, A. J. & McCrory, P. Increasing incidence of hospitalisation for sport-related concussion in Victoria, Australia. Med. J. Aust. 198, 427430 (2013).
  41. Wafa, S. W. et al. Association between physical activity and health-related quality of life in children: a cross-sectional study. Health Qual. Life Outcomes 14, 71 (2016).
  42. McCabe, K. O., Modecki, K. L. & Barber, B. L. Participation in organized activities protects against adolescents' risky substance use, even beyond development in conscientiousness. J. Youth Adolesc. http://dx.doi.org/10.1007/s10964-016-0454-x (2016).
  43. Pate, R. R., Trost, S. G., Levin, S. & Dowda, M. Sports participation and health-related behaviors among US youth. Arch. Pediatr. Adolesc. Med. 154, 904911 (2000).
  44. Dodge, T. & Lambert, S. F. Positive self-beliefs as a mediator of the relationship between adolescents' sports participation and health in young adulthood. J. Youth Adolesc. 38, 813825 (2009).
  45. Vella, S. A., Cliff, D. P., Magee, C. A. & Okely, A. D. Sports participation and parent-reported health-related quality of life in children: longitudinal associations. J. Pediatr. 164, 14691474 (2014).
  46. Noda, H. et al. Walking and sports participation and mortality from coronary heart disease and stroke. J. Am. Coll. Cardiol. 46, 17611767 (2005).
  47. Olson, H. W., Teitelbaum, H., Van Huss, W. D. & Montoye, H. J. Years of sports participation and mortality in college athletes. J. Sports Med. Phys. Fitness 17, 321326 (1977).
  48. Sabo, D., Miller, K. E., Melnick, M. J., Farrell, M. P. & Barnes, G. M. High school athletic participation and adolescent suicide: a nationwide US study. Int. Rev. Sociol. Sport 40, 523 (2005).
  49. Dobosz, R. P. & Beaty, L. A. The relationship between athletic participation and high school students' leadership ability. Adolescence 34, 215220 (1999).
  50. Tymula, A. et al. Adolescents' risk-taking behavior is driven by tolerance to ambiguity. Proc. Natl Acad. Sci. USA 109, 1713517140 (2012).
  51. Institute of Medicine (US) and National Research Council (US) Committee on the Science of Adolescence. The Science of Adolescent Risk-Taking: Workshop Report (The National Academies Press, 2011).

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Author information

Affiliations

  1. Rebekah Mannix is in the Division of Emergency Medicine, 300 Longwood Avenue, Boston, Massachusetts 02115, USA.

  2. William P. Meehan is in the Division of Sports Medicine at the Boston Children's Hospital, 300 Longwood Avenue, Boston, Massachusetts 02115, USA.

    • William P. Meehan III
  3. Alvaro Pascual-Leone is in the Division of Cognitive Neurology at the Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, Massachusetts 02115, USA.

Contributions

All authors researched data for article, discussed its content, and wrote and edited the article before submission.

Competing interests statement

R.M. and W.P.M.'s research is supported by funding from the National Hockey League Alumni Association through the Corey C. Griffin Pro-Am Tournament. The work of W.P.M., A.P.-L. and R.M. is supported by the Football Players Health Study at Harvard University. W.P.M. receives royalties from ABC-Clio publishing for the sale of his book Kids, Sports, and Concussion: A Guide for Coaches and Parents, and royalties from Wolters Kluwer for working as an author for UpToDate. He is under contract with ABC-Clio publishing for a future book entitled Concussions, and with Springer International Publishing for a future book entitled Head and Neck Injuries in Young Athletes. The content of this article is solely the responsibility of the authors and does not necessarily represent the official views of Harvard Catalyst, Harvard University and its affiliated academic health-care centres, the NIH, the Sidney R. Baer, Jr. Foundation, or the National Football League Players Association.

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Author details

  • Rebekah Mannix

    Rebekah Mannix is a staff physician in emergency medicine at Boston Children's Hospital, Massachusetts, USA, where she also serves as Co-Director of the Brain Injury Center. She is an Assistant Professor of Paediatrics and Emergency Medicine at Harvard Medical School in Boston. She conducts both clinical and preclinical traumatic brain injury and pediatric trauma research.

  • William P. Meehan III

    William P. Meehan III is Director of the Micheli Center for Sports Injury Prevention, Director of Research for the Brain Injury Center at Boston Children's Hospital, Massachusetts, USA, and Co-Director of The Football Players Health Study at Harvard University in Boston. He graduated from Harvard Medical School where he is currently an Assistant Professor of Paediatrics and Orthopaedics. He conducts both clinical and scientific research in the area of sports injuries and concussive brain injury.

  • Alvaro Pascual-Leone

    Alvaro Pascual-Leone is Professor of Neurology and an Associate Dean for Clinical and Translational Research at Harvard Medical School, Boston, Massachussetts, USA. He serves as Chief for the Division of Cognitive Neurology and the Director of the Berenson-Allen Center for Noninvasive Brain Stimulation at Beth Israel Deaconess Medical Center in Boston. Pascual-Leone's research aims at understanding the mechanisms that control brain plasticity in order to identify new therapeutic interventions to treat cognitive impairment and dementia.

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