Emergency Department Visits by Older Adults for Motor Vehicle Collisions

Introduction: To describe the epidemiology and characteristics of emergency department (ED) visits by older adults for motor vehicle collisions (MVC) in the United States (U.S.). Methods: We analyzed ED visits for MVCs using data from the 2003-2007 National Hospital Ambulatory Medical Care Survey (NHAMCS). Using U.S. Census data, we calculated annual incidence rates of driver or passenger MVC-related ED visits and examined visit characteristics, including triage acuity, tests performed and hospital admission or discharge. We compared older (65+ years) and younger (18-64 years) MVC patients and calculated odds ratios (OR) and 95% confidence intervals (CIs) to measure the strength of associations between age group and various visit characteristics. Multivariable logistic regression was used to identify independent predictors of admissions for MVC-related injuries among older adults. Results: From 2003-2007, there were an average of 237,000 annual ED visits by older adults for MVCs. The annual ED visit rate for MVCs was 6.4 (95% CI 4.6-8.3) visits per 1,000 for older adults and 16.4 (95% CI 14.0-18.8) visits per 1,000 for younger adults. Compared to younger MVC patients, after adjustment for gender, race and ethnicity, older MVC patients were more likely to have at least one imaging study performed (OR 3.69, 95% CI 1.46-9.36). Older MVC patients were not significantly more likely to arrive by ambulance (OR 1.47; 95% CI 0.76-2.86), have a high triage acuity (OR 1.56; 95% CI 0.77-3.14), or to have a diagnosis of a head, spinal cord or torso injury (OR 0.97; 95% CI 0.42-2.23) as compared to younger MVC patients after adjustment for gender, race and ethnicity. Overall, 14.5% (95% CI 9.8-19.2) of older MVC patients and 6.1% (95% CI 4.8-7.5) of younger MVC patients were admitted to the hospital. There was also a non-statistically significant trend toward hospital admission for older versus younger MVC patients (OR 1.78; 95% CI 0.71-4.43), and admission to the ICU if hospitalized (OR 6.9, 95% CI 0.9-51.9), after adjustment for gender, race, ethnicity, and injury acuity. Markers of injury acuity studied included EMS arrival, high triage acuity category, ED imaging, and diagnosis of a head, spinal cord or internal injury. Conclusion: Although ED visits after MVC for older adults are less common per capita, older adults are more commonly admitted to the hospital and ICU. Older MVC victims require significant ED resources in terms of diagnostic imaging as compared to younger MVC patients. As the U.S. population ages, and as older adults continue to drive, EDs will have to allocate appropriate resources and develop diagnostic and treatment protocols to care for the increased volume of older adult MVC victims.