Influence of the College Football Athletes' Cumulative Head Impact Exposure (HIE) on the mTBI incidence and post-mTBI health outcomes

Project Abstract Sport-related concussion (SRC) is a significant public health problem resulting in over 200,000 annual trips to the Emergency Department (ED) in the United States with as many as 3.8 million SRCs occurring annually. From a biomechanical standpoint, the concussion mechanism includes head impact resulting in high magnitude head rotational accelerations. Human studies measuring the accelerations associated with concussive head impacts developed injury risk curves that can be extremely useful from the clinical and safety perspectives. However, recent literature has shown that acceleration magnitudes associated with concussive impacts are extremely variable and not necessarily distinct from the routinely sustained head impact magnitudes. Mounting evidence from human studies has demonstrated that repetitive head impact exposure (HIE) may contribute to decreased SRC tolerance in contact sport athletes. Studies focused on quantifying the relationship between the HIE and incident concussion have been underpowered, as there were limited number of concussions occurring during the observation period. We will utilize the data from the NCAA-DoD Concussion Assessment, Research and Education Consortium (CARE) Head Impact Measurement Core, the largest and most comprehensive study of SRC and repetitive HIE to date, and data from Project Head-to-Head 2 (PHTH2), a large-scale study of SRC and HIE in both collegiate and high school athletes to: (1) determine the association of HIE to SRC occurrence and post-SRC recovery based on the frequency, number, recency, and severity of head impacts sustained in football activities; and (2) build a dynamic predictive algorithm of the SRC risk based on the HIE time series data obtained from the HIT System and other factors, including demographics, concussion history, impact characteristics, and network measures.