Abstract
Introduction: Concussions are a public health concern in Canada, and may cause physiological and neuropsychological consequences. Research on risk factors is not extensive and many questions remain unanswered. Objective: This study examined whether cognitive functioning, history of concussion (HOC), and sex predicted risk of sport concussion. Design: Retrospective study design using logistic regression and predictive models. Participants: 708 data observations from 701 varsity athletes (41.2% female), representing 14 sports. Assessment of Risk Factors: Two measures of cognitive functioning (mean reaction time and throughput [speed and accuracy]) were assessed using the Automated Neuropsychological Assessment Metrics testing battery. Sex and self-reported HOC were examined. Outcome Measures: Occurrence of concussion after baseline testing. Main Results: HOC was a significant predictor for both sexes. For every previous concussion, the odds of sustaining another concussion increased by 1.5 (95% Confidence Interval [CI]: 1.1, 2.1 [females]; 1.2, 1.9 [males]). Females with a HOC had twice the odds of sustaining another concussion than those without a HOC (CI: 1.1, 4.0). For males, the odds were three times (CI: 1.7, 5.6). Cognitive functioning and sex were not meaningful predictors. Conclusions: This study provides sex-specific evidence that HOC is a risk factor and suggests that pre-injury cognitive functioning is not a risk factor for sport concussion. Thus, it is important for clinicians to record HOC, and to encourage athletes to report concussions to ensure accurate recording. Despite common practice, pre-injury cognitive screening of athletes is not recommended for assessing risk of future concussion.Acknowledgments: The researchers would like to acknowledge the participating University of Toronto varsity athletes and coaches, and the David L. MacIntosh Sport Medicine Clinic