Objective: To evaluate the association between apolipoprotein E (APOE) polymorphisms (E2, C/T Arg158Cys; E4, T/C Cys112Arg; and promoter, g-219t) and the history of concussion in college athletes. We hypothesized that carrying 1 or more APOE rare (or minor) allele assessed in this study would be associated with having a history of 1 or more concussions.
Design: Multicenter cross-sectional study.
Setting: University athletic facilities.
Participants: One hundred ninety-six male football (n = 163) and female soccer (n = 33) college athletes volunteered.
Interventions: Written concussion history questionnaire and saliva samples for genotyping.
Main Outcome Measures: Self-reported history of a documented concussion and rare APOE genotype (E2, E4, promoter).
Results: There was a significant association (Wald χ2 = 3.82; P = 0.05; odds ratio = 9.8) between carrying all APOE rare alleles and the history of a previous concussion. There was also a significant association (Wald χ2 = 3.96, P = 0.04, odds ratio = 8.4) between carrying the APOE promoter minor allele and experiencing 2 or more concussions.
Conclusions: Carriers of all 3 APOE rare (or minor) alleles assessed in this study were nearly 10 times more likely to report a previous concussion and may be at a greater risk of concussion versus noncarriers. Promoter minor allele carriers were 8.4 times more likely to report multiple concussions and may be at a greater risk of multiple concussions versus noncarriers. Research involving larger samples of individuals with multiple concussions and carriers of multiple APOE rare alleles is warranted.
From the *Department of Kinesiology; Temple University, Philadelphia, Pennsylvania; †Department of Health, Physical Education & Recreation, Lincoln University, Philadelphia, Pennsylvania; ‡Department of Kinesiology, Towson University, Towson, Maryland; §Biostatistics Consulting Center, Temple University School of Medicine, Philadelphia, Pennsylvania; and ¶Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, Pennsylvania.
Submitted for publication February 15, 2010; accepted September 11, 2010.
Supported by the Jayne Haines Center for Pharmacogenomics and Drug Safety of the Temple University School of Pharmacy.
The authors report no conflicts of interest.
Reprints: Ryan T. Tierney, PhD, Department of Kinesiology, Temple University, 018 Pearson Hall, 1800 North Broad St, Philadelphia, PA 19122 (e-mail: email@example.com).