Home » Head Trauma Strongly Linked To Chronic Traumatic Encephalopathy But Precise Relationship Not Yet Known

Head Trauma Strongly Linked To Chronic Traumatic Encephalopathy But Precise Relationship Not Yet Known

Other risk factors for CTE, incidence rate not yet known; connection has been "greatly overstated" says Cantu

Causal link likely exists, just not yet proven 

It is important to emphasize that such researchers are not saying that such a causal link won't ever be established. As Gardner admits,  "Ultimately, scientific research might establish that participation in contact sports leads to a distinct neuropathological syndrome, and this neuropathology causes psychiatric, cognitive and physical problems."[19]   

Indeed, the authors of one recent paper[40] acknowledge that "it simply makes good clinical sense to continue practices to minimize the number of concussions sustained and that allow for adequate recovery after any concussion" while awaiting the results of such studies. The authors of the 2015 BJSM editorial on CTE[67] take the same view: "Despite uncertainties, strategies to reduce the number of concussive and subconcussive head impacts in American football [and in other sports, presumably, such as soccer, lacrosse, and hockey] should be a top priority."

At the same time, however, they say it is "essential to avoid embracing preliminary results derived from relatively small case numbers and methodologically problematic studies as undisputed medical fact, and to allow such results to redirect clinical practice away from established standards."

A concerted effort is thus needed, they say, to educate medical professionals and the public at large regarding the state of the science of mTBI and CTE in order to avoid "catastrophizing" mTBI, to mitigate the "collective anxiety" that has resulted, and to reduce the likelihood that outcomes after mTBI will be actually be made worse as a result of the media frenzy around CTE.


Sources: 

McKee A, Cantu R, et. al. Chronic Traumatic Encephalopathy in Athletes: Progressive Tauopathy After Repetitive Head Injury. J Neuro Exp. Neurol  2009; 68(7): 709-735

Gavett B, Stern R, Cantu R, Nowinski C, McKee A. Mild traumatic brain injury: a risk factor for neurodegeneration.  Alzheimer's Research & Therapy 2010; 2:18

Galetta KM, Barret J, Allen M, et. al. "The King-Devick test as a determinant of head trauma and concussion in boxers and MMA fighters." Neurology 2011; Prepublished online February 2, 2011.

Daneshvar DH, Baugh CM, et. al. Helmets and Mouth Guards: The Role of Personal Equipment in Preventing Sports-Related Concussion.  Clin Sports Med 2011;30:145-163. 

Footnotes: 

1.  Lincoln A, Caswell S, Almquist J, Dunn R, Norris J, Hinton R. Trends in Concussion Incidence in High School Sports: A Prospective 11-Year Study. Am J Sports Med 2011;30(10) accessed January 31, 2011 @ http://ajs.sagepub.com/content/early/2011/01/29/0363546510392326.full.pd...

2. Schatz P, Moser RS, Covassin T, Karpf.  Early Indicators of Enduring Symptoms in High School Athletes with Multiple Previous Concussions.  Neurosurgery (accepted for publication); 2011 at n. 3-5.

3. Stern R, Riley D, Daneshvar D, Nowinski C, Cantu R, McKee A. Long-term Consequences of Repetitive Brain Trauma: Chronic Traumatic Encephalopathy.  Phys Med & Rehab. 2011;3;S460-S467. DOI:10.1016/j.pmrj.2011.08.008. 

4. Boston University Center for Alzheimer's Research. Selected CSTE Cases: Eighteen year old high school football player. 2010; http://www.bu.edu/cste/case-studies/18-year-old/ (Accessed March 2, 2011). 

5. Talavage T, Nauman E, Breedlove E, et. al. Functionally-Detected Cognitive Impairment in High School Football Players Without Clinically-Diagnosed Concussion. J Neurotrauma. 2010; DOI: 10.1089/neu.2010.1512.

6. Crisco JJ, Fiore R, Beckwith JG, et al. Frequency and location of head impact exposures in individual collegiate football players.  J. Athl Train 2010;45:549-559.

7. Field M, Collins MW, Lovell MR, Maroon J. Does age play a role in recovery from sports related concussion? A comparison of high school and collegiate athletes.  J Pediatr. 2003;414:546-553.

8. Pullela R, Raber J, Pfankuch T. et al. Traumatic injury to the immature brain results in progressive neuronal loss, hyperactivity and delayed cognitive impairments.  Dev Neurosci 2006;28:396-409. 

9. Kirkwood MW, Randolph C, Yeates KO. Sport-Related Concussion: A Call for Evidence and Perspective Amidst the Alarms.  Clin J Sport Med 2012;22(5):383-384.

10. Zuckerman SL, Solomon GS, Forbes JA, Haase RF, Sills AK, Lovell MR.  Response to acute concussive injury in soccer players: is gender a modifying factor?  J Neurosurg: Pediatrics 2012; DOI:10.3171/2012.8.PEDS12139 (published online ahead of print October 2, 2012)(accessed October 15, 2012). 

11. Bazarian JJ, Zhu T, Blyth B, Borrino A, Zhong J.  Subject-specific changes in brain white matter in diffusion tensor imaging after sports-related concussion.  Magnetic Resources Imaging. 2012; 30(2): 171-180.

12. March N, Bazarian JJ, Puvenna V, Janigro M, Ghosh C, et. al. Consequences of Repeated Blood-Brain Barrier Disruption in Football Players. PLoS ONE 2013;8(3): e56805. doi: 10.1371/journal.pone.0056805. 

13. 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 2013;47:250-258. 

14. McKee A, et al. The spectrum of disease in chronic traumatic encephalopathy. Brain 2012; doi:10.1093/brain/aws307 (published online ahead of print December 2, 2012)(accessed March 20, 2013). 

15. D'Alessandro D, "Scientists claim that link between concussions and CTE is "unproven" could impact NFL lawsuits." NewJersey.com (March 17, 2013)http://www.nj.com/ledger-dalessandro/index.ssf/2013/03/scientists_claim_that_link_between_concussions_and_cte_is_unproven_could_impact_nfl_lawsuits.html (accessed March 20, 2013).

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31. David Epstein. The Damage Done: While Concussive Hits Dominate the Debate, A Groundbreaking New Study Suggests That Minor Blows - And There Can Be Hundreds Each Game - Are Just As Traumatic. Sports Illustrated. November 1, 2010 (accessed October 14, 2013 at http://sportsillustrated.cnn.com/vault/article/magazine/MAG1176377/2/). 

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Originally posted February 8, 2011 Last updated November 16, 2015