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- Garcia-Cordero, Indira, et al.
(författare)
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Functional connectivity changes in neurodegenerative biomarker-positive athletes with repeated concussions
- 2024
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Ingår i: JOURNAL OF NEUROLOGY. - 0340-5354 .- 1432-1459.
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Tidskriftsartikel (refereegranskat)abstract
- Multimodal biomarkers may identify former contact sports athletes with repeated concussions and at risk for dementia. Our study aims to investigate whether biomarker evidence of neurodegeneration in former professional athletes with repetitive concussions (ExPro) is associated with worse cognition and mood/behavior, brain atrophy, and altered functional connectivity. Forty-one contact sports athletes with repeated concussions were divided into neurodegenerative biomarker-positive (n = 16) and biomarker-negative (n = 25) groups based on positivity of serum neurofilament light-chain. Six healthy controls (negative for biomarkers) with no history of concussions were also analyzed. We calculated cognitive and mood/behavior composite scores from neuropsychological assessments. Gray matter volume maps and functional connectivity of the default mode, salience, and frontoparietal networks were compared between groups using ANCOVAs, controlling for age, and total intracranial volume. The association between the connectivity networks and sports characteristics was analyzed by multiple regression analysis in all ExPro. Participants presented normal-range mean performance in executive function, memory, and mood/behavior tests. The ExPro groups did not differ in professional years played, age at first participation in contact sports, and number of concussions. There were no differences in gray matter volume between groups. The neurodegenerative biomarker-positive group had lower connectivity in the default mode network (DMN) compared to the healthy controls and the neurodegenerative biomarker-negative group. DMN disconnection was associated with increased number of concussions in all ExPro. Biomarkers of neurodegeneration may be useful to detect athletes that are still cognitively normal, but with functional connectivity alterations after concussions and at risk of dementia.
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| 2. |
- Vasilevskaya, Anna, et al.
(författare)
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18F-Flortaucipir (AV1451) imaging identifies grey matter atrophy in retired athletes
- 2024
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Ingår i: JOURNAL OF NEUROLOGY. - 0340-5354 .- 1432-1459.
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundThe long-term consequences of concussions may include pathological neurodegeneration as seen in Alzheimer's disease (AD) and chronic traumatic encephalopathy (CTE). Tau-PET showed promise as a method to detect tau pathology of CTE, but more studies are neededObjectiveThis study aimed (1) to assess the association of imaging evidence of tau pathology with brain volumes in retired athletes and (2) to examine the relationship between tau-PET and neuropsychological functioning.MethodsFormer contact sport athletes were recruited through the Canadian Football League Alumni Association or the Canadian Concussion Centre clinic. Athletes completed MRI, [18F]flortaucipir tau-PET, and a neuropsychological battery. Memory composite was created by averaging the Rey Auditory Verbal Learning Test and Rey Visual Design Learning Test z-scores. Grey matter (GM) volumes were age/intracranial volume corrected using normal control MRIs. Tau-PET % positivity in GM was calculated as the number of positive voxels (>= 1.3 standardized uptake value ratio (SUVR)/total voxels).Results47 retired contact sport athletes negative for AD (age:51 +/- 14; concussions/athlete:15 +/- 2) and 54 normal controls (age:50 +/- 13) were included. Tau-PET positive voxels had significantly lower GM volumes, compared to tau-PET negative voxels (- 0.37 +/- 0.41 vs. - 0.31 +/- 0.37, paired p = .006). There was a significant relationship between GM tau-PET % positivity and memory composite score (r = - .366, p = .02), controlled for age, PET scanner, and PET scan duration. There was no relationship between tau-PET measures and concussion number, or years of sport played.ConclusionA higher tau-PET signal was associated with reduced GM volumes and lower memory scores. Tau-PET may be useful for identifying those at risk for neurodegeneration.
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