Does the apolipoprotein epsilon 4 allele predispose varsity athletes to concussion? A prospective cohort study.
OBJECTIVE
To determine the association between the apolipoprotein epsilon 4 allele and concussion. We hypothesized that apolipoprotein epsilon 4 carriers may be more likely to sustain a concussion.


METHODS
Prospective cohort study.


METHODS
University of Toronto varsity athletics.


METHODS
Included 318 of 822 collegiate student athletes who participated in University of Toronto varsity sports from September 2002 to April 2006.


METHODS
The presence of apolipoprotein epsilon 4 was described dichotomously after genotyping blood samples collected from participants.


METHODS
Concussions were identified by sport-medicine professionals present on the sidelines using on-field assessment forms. All concussion diagnoses were verified by a sports medicine physician. Survival analysis was used to determine the association between apolipoprotein epsilon 4 and first concussion.


RESULTS
The unadjusted hazard ratio for concussion in the apolipoprotein epsilon 4 carriers was 1.18 (95% CI: 0.52, 2.69) compared to noncarriers. Adjustment for sex, weight, height, and team type resulted in a hazard ratio of 1.06 (95% CI: 0.41, 2.72), indicating little effect from confounding factors.


CONCLUSIONS
There is no important association between carrying the apolipoprotein epsilon 4 allele and sustaining a concussion. At this time, we do not recommend preseason genetic testing for varsity athletes as a mechanism for targeting prevention strategies.
Kristman
Vicki L
VL
Department of Public Health Sciences, University of Toronto, Toronto, Ontario, Canada. vicki.kristman@uhnresearch.ca
Tator
Charles H
CH
Kreiger
Nancy
N
Richards
Doug
D
Mainwaring
Lynda
L
Jaglal
Susan
S
Tomlinson
George
G
Comper
Paul
P
D000293:Adolescent; D000328:Adult; D000483:Alleles; D053327:Apolipoprotein E4 / Q000235:genetics*; D001265:Athletic Injuries / Q000235:genetics*; D001924:Brain Concussion / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D011446:Prospective Studies; D013334:Students
D053327:Apolipoprotein E4