Genetic polymorphisms associated with the risk of concussion in 1056 college athletes: a multicentre prospective cohort study.

Abstract

To evaluate the association of genetic polymorphisms APOE, <i>APOE</i> G-219T promoter, microtubule associated protein(MAPT)/<i>tau</i> exon 6 Ser⁵³Pro, MAPT/<i>tau</i> Hist⁴⁷Tyr, <i>IL-6</i>572 G/C and <i>IL-6R</i>^Asp358^Ala with the risk of concussion in college athletes. A 23-centre prospective cohort study of 1056 college athletes with genotyping was completed between August 2003 and December 2012. All athletes completed baseline medical and concussion questionnaires, and post-concussion data were collected for athletes with a documented concussion. The study cohort consisted of 1056 athletes of mean±SD age 19.7±1.5 years<b>,</b> 89.3% male, 59.4% Caucasian, 35.0% African-American, 5.6% other race. The athletes participated in American football, soccer, basketball, softball, men's wrestling and club rugby. A total of 133 (12.1% prevalence) concussions occurred during an average surveillance of 3 years per athlete. We observed a significant positive association between <i>IL-6R</i> CC (p=0.001) and a negative association between <i>APOE</i>4 (p=0.03) and the risk of concussion. Unadjusted and adjusted logistic regression analysis showed a significant association between <i>IL-6R</i> CC and concussion (OR 3.48; 95% CI 1.58 to 7.65; p=0.002) and between the APOE4 allele and concussion (OR 0.61; 95% CI 0.38 to 0.96; p=0.04), which persisted after adjustment for confounders. <i>IL-6R</i> CC was associated with a three times greater concussion risk and <i>APOE</i>4 with a 40% lower risk.