Interaction of APOE4 alleles and PET tau imaging in former contact sport athletes

Neuroimage Clin. 2020:26:102212. doi: 10.1016/j.nicl.2020.102212. Epub 2020 Feb 13.

Abstract

Background: Genetic polymorphisms like apolipoprotein E (APOE) and microtubule-associated protein tau (MAPT) genes increase the risk of neurodegeneration.

Methods: 38 former players (age 52.63±14.02) of contact sports underwent neuroimaging, biofluid collection, and comprehensive neuropsychological assessment. The [F-18]AV-1451 tracer signal was compared in the cortical grey matter between APOE4 allele carriers and non-carriers as well as carriers of MAPT H1H1 vs non-H1H1. Participants were then divided into the high (N = 13) and low (N = 13) groups based on cortical PET tau standard uptake value ratios (SUVRs) for comparison.

Findings: Cortical grey matter PET tau SUVR values were significantly higher in APOE4 carriers compared to non-carriers (p = 0.020). In contrast, there was no significant difference in SUVR between MAPT H1H1 vs non-H1H1 carrier genes (p = 1.00). There was a significantly higher APOE4 allele frequency in the high cortical grey matter PET tau group, comparing to low cortical grey matter PET tau group (p = 0.048). No significant difference in neuropsychological function was found between APOE4 allele carriers and non-carriers.

Interpretation: There is an association between higher cortical grey matter tau burden as seen with [F-18]AV-1451 PET tracer SUVR, and the APOE4 allele in former professional and semi-professional players at high risk of concussions. APOE4 allele may be a risk factor for tau accumulation in former contact sports athletes at high risk of neurodegeneration.

Funding: Toronto General and Western Hospital Foundations; Weston Brain Institute; Canadian Consortium on Neurodegeneration in ageing; Krembil Research Institute. There was no role of the funders in this study.

Keywords: Apoe4; Chronic traumatic encephalopathy; Concussion; Positron emission tomography; Tau.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Alleles
  • Apolipoprotein E4 / genetics*
  • Athletes
  • Athletic Injuries / genetics*
  • Athletic Injuries / pathology
  • Brain / pathology*
  • Canada
  • Chronic Traumatic Encephalopathy / genetics*
  • Female
  • Genetic Predisposition to Disease / genetics*
  • Gray Matter / metabolism
  • Gray Matter / pathology
  • Heterozygote
  • Humans
  • Male
  • Middle Aged
  • Positron-Emission Tomography
  • tau Proteins / genetics*

Substances

  • Apolipoprotein E4
  • MAPT protein, human
  • tau Proteins