Objectives: Concussion is the most common type of mild traumatic brain injury for which patients present to the emergency department (ED). It is critical to understand the contemporary epidemiology of concussion and rates of head computed tomography (CT) use in head-injured patients to inform education of evidence-based clinical practice guidelines to emergency medicine providers.
Methods: This was a cross-sectional analysis of the Nationwide Emergency Department Sample (NEDS) for years 2006 to 2011, representing a stratified probability sample of all U.S. hospital-based EDs. Patients of all ages with concussion diagnoses were included, and those with intracranial hemorrhages or prolonged loss of consciousness were excluded. Descriptive and bivariate statistics were summarized for patient demographics, injury mechanism, Injury Severity Scores (ISS), and concussion incidence rates, based on U.S. Census Bureau population estimates.
Results: There were 756,214,762 (weighted) ED visits in the NEDS between 2006 and 2011, of which 0.5% received diagnoses of concussion. The national incidence rate of concussion visits increased 22.6% from 195 visits per 100,000 person-years in 2006 to 239 visits per 100,000 person-years in 2011. The incidence of concussion visits increased by 28.1% from 2006 to 2011 overall (580,573 to 743,994) and within all age group categories. The rate of head CT use in patients diagnosed with concussion increased 35.7% (range = 34.5% to 46.8%) for the entire group from 2006 to 2011 (p < 0.0001). The injury severity of patients' injuries decreased over time (66.4% ISS < 5 in 2006 and 75% in 2011; p < 0.0001), while the proportion of discharged patients increased over time (78.1% in 2006 and 86.6% in 2011; p < 0.0001).
Conclusions: ED visits for concussions have increased over time, with a corresponding increase in head CT utilization despite a decrease in injury severity. Increased visits may be due to more concussion awareness and recognition of subtle injuries. Evidence-based clinical practice guidelines for neuroimaging in head-injured patients and management of concussion should be reinforced to emergency medicine providers.
© 2015 by the Society for Academic Emergency Medicine.