Objective: To investigate associations of APOE, APOE promoter (G-219T), and tau protein exon 6 polymorphisms (His47Tyr and Ser53Pro) and a history of self-reported concussion in college athletes.
Design: Multi-center cross-sectional study.
Setting: Male football and male and female soccer programs at the University of South Carolina, Jacksonville University, Benedict College, and the College of Charleston.
Participants: Active 18- to 30-year-old (n = 195) intercollegiate male football players and male and female soccer players during 2001 and 2002.
Assessment of Risk Factors: Written questionnaires and blood or mouthwash samples for DNA for genotyping by RFLP/PCR.
Main Outcome Measurement: Self-reported history of concussions over the previous 8 years.
Results: A statistically significant, nearly 3-fold increase in risk of a history of concussion for those with the APOE promoter G-219T TT genotype relative to the GG genotype (OR, 2.8; 95% CI, 1.1 to 6.9) adjusted for age, sport, school, and years in their primary sport, a finding that was stronger for Cantu grade 2 and 3 concussions.
Conclusions: These results suggest that college athletes with an APOE promoter G-219T TT genotype may be at increased risk for having a history of concussions, especially more severe concussions. Although there was some support for the possibility that the tau Ser53Pro polymorphism may be associated with increased risk of prior concussion (OR, 2.1; 95% CI, 0.3 to 14.5), there was no support for an association with APOE genotypes. The results of this cross-sectional study support the need for a prospective study of genetic factors, such as APOE promoter polymorphisms, and the incidence of and sequelae from concussions in college athletes.
From the *Department of Family Medicine, Brody School of Medicine at East Carolina University, Greenville, North Carolina; †Department of Epidemiology and Department of Hematology & Oncology, Rollins School of Public Health, Emory University, Atlanta, Georgia; ‡Department of Neuropsychiatry, University of South Carolina School of Medicine, Columbia, South Carolina; §Molecular Epidemiologic Research Lab, Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, South Carolina; ¶Department of Orthopedic Surgery, Medical University of South Carolina, Charleston, South Carolina; ∥Department of Surgery, Emerson Hospital, Concord, Massachusetts; and **Department of Family and Preventive Medicine, University of South Carolina School of Medicine, Columbia, South Carolina.
Submitted for publication October 25, 2006; accepted July 15, 2007.
The primary author acknowledges grant funding for this project through the University of South Carolina School of Medicine Research Development Fund.
The authors state that they have no financial interest in the products mentioned within this article.
Correspondence: Thomas Roland Terrell, MD, MPhil, Brody School of Medicine at ECU, Department of Family Medicine, 600 Moye Boulevard, Brody 4N-51, Greenville, NC 27834 (e-mail: email@example.com).