Epidemiology of Isolated Versus Nonisolated Mild Traumatic Brain Injury Treated in Emergency Departments in the United States, 2006-2012: Sociodemographic Characteristics.

Objectives: To describe the frequencies and rates of mild traumatic brain injury (mTBI) emergency department (ED) visits, analyze the trend across the years, and compare sociodemographic characteristics of visits by mTBI type (ie, mTBI as the only injury, or present along with other injuries).

Design: Population-based descriptive study using data from the Nationwide Emergency Department Sample (2006-2012).

Methods: Joinpoint regression was used to calculate the average annual percent changes of mTBI incidence rates. Characteristics between isolated and nonisolated visits were compared, and the odds ratios were reported.

Results: The rate per 100 000 population of mTBI ED visits in the United States increased significantly from 569.4 (in 2006) to 807.9 (in 2012). The highest rates were observed in 0- to 4-year-olds, followed by male 15- to 24-year-olds and females 65 years and older; the lowest rates were among 45- to 64-year-olds. The majority (70%) of all visits were nonisolated and occurred more frequently in residents of metropolitan areas. Falls were the leading external cause. Most visits were privately insured or covered by Medicare/Medicaid, and the injury occurred on weekdays in predominantly metropolitan hospitals in the South region.

Conclusions: The burden of mTBI in US EDs is high. Most mTBI ED visits present with other injuries. Awareness of sociodemographic factors associated with nonisolated mTBI may help improve diagnosis in US EDs. This information has implications for resource planning and mTBI screening in EDs.