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Repeated Sport-Related Concussion Shows Only Minimal White Matter Differences Many Years After Playing High School Football

Published online by Cambridge University Press:  06 August 2019

Douglas P. Terry ,
Catherine M. Mewborn  and
L. Stephen Miller Open the ORCID record for L. Stephen Miller [Opens in a new window]
Douglas P. Terry
Affiliation:
Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, MA 02129, USA
Catherine M. Mewborn
Affiliation:
Department of Psychology, University of Georgia, Athens, GA 30602, USA
L. Stephen Miller*
Affiliation:
Department of Psychology, University of Georgia, Athens, GA 30602, USA
*
Correspondence and reprint requests to: L. Stephen Miller, 125 Baldwin Street, Psychology Bldg Rm 202, University of Georgia, Athens, GA 30602. E-mail: [email protected]
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Abstract

Objective: Multiple concussions sustained in youth sport may be associated with later-life brain changes and worse cognitive outcomes. We examined the association between two or more concussions during high school football and later-life white matter (WM) microstructure (i.e., 22–47 years following football retirement) using diffusion tensor imaging (DTI). Method: Forty former high school football players aged 40–65 who received 2+ concussions during high school football (N = 20), or denied concussive events (N = 20) were recruited. Participants underwent neurocognitive testing and DTI scanning. Results: Groups did not statistically differ on age, education, or estimated pre-morbid intelligence. Tract-based Spatial Statistics (TBSS) correcting for Family-Wise Error (FWE)(p < .05) did not yield differences between groups at the whole-brain level. Region of interest analyses showed higher mean diffusivity (MD) in the anterior limb of the internal capsule (ALIC) in the concussed group compared to the non-concussed former players. More liberal analyses (i.e., p < .001, uncorrected for multiple comparisons, ≥8 voxels) also revealed that former players endorsing 2+ concussions had higher MD in the ALIC. Analyses that covaried for age did not reveal differences at either threshold. Concussive histories were not associated with worse cognitive functioning, nor did it impact the relationship between neuropsychological scores and DTI metrics. Discussion: Results suggest only minimal neuroanatomical brain differences in former athletes many years following original concussive injuries compared to controls.

Keywords

Diffusion tensor imagingFormer athletesmTBIMiddle ageCognition
Type
Regular Research
Information
Journal of the International Neuropsychological Society , Volume 25 , Issue 9 , October 2019 , pp. 950 - 960
Copyright
Copyright © INS. Published by Cambridge University Press, 2019. 

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