Cortical thinning in former professional soccer players
Soccer is the most popular sport in the world. Soccer players are at high risk for repetitive subconcussive head impact when heading the ball. Whether this leads to long-term alterations of the brain’s structure associated with cognitive decline remains unknown. The aim of this study was to evaluate cortical thickness in former professional soccer players using high-resolution structural MR imaging. Fifteen former male professional soccer players (mean age 49.3 [SD 5.1] years) underwent high-resolution structural 3 T MR imaging, as well as cognitive testing. Fifteen male, age-matched former professional non-contact sport athletes (mean age 49.6 [SD 6.4] years) served as controls. Group analyses of cortical thickness were performed using voxel-based statistics. Soccer players demonstrated greater cortical thinning with increasing age compared to controls in the right inferolateral-parietal, temporal, and occipital cortex. Cortical thinning was associated with lower cognitive performance as well as with estimated exposure to repetitive subconcussive head impact. Neurocognitive evaluation revealed decreased memory performance in the soccer players compared to controls. The association of cortical thinning and decreased cognitive performance, as well as exposure to repetitive subconcussive head impact, further supports the hypothesis that repetitive subconcussive head impact may play a role in early cognitive decline in soccer players. Future studies are needed to elucidate the time course of changes in cortical thickness as well as their association with impaired cognitive function and possible underlying neurodegenerative process.
KeywordsRepetitive subconcussive head impact Soccer Cortical thickness Aging Traumatic brain injury
Barrett Impulsivity Score
Balance error scoring system
Rey osterrieth complex figure
Repetitive subconcussive head impact
- TMT A
Trailmaking Test A
- TMT B
Trailmaking Test B
This study was supported by the Else Kröner-Fresenius Stiftung, Germany (IK). This work was also partially funded by grants from The Department of Defense (X81XWH-07-CC-CSDoD; RZ, MES) and a VA Merit Award (MES). Michael Mayinger was supported by the Petraeic Legate foundation, Germany.
Conflict of interest
All authors declare that they have no conflict of interest.
Compliance with ethical standards
All procedures performed in this study involving human participants were in accordance with the ethical standards of the responsible institutional committee on human experimentation and with the Helsinki Declaration of 1975, and the applicable revisions. Written informed consent was obtained from all study participants prior to inclusion in the study.
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