Acute medical impairment among elderly patients involved in motor vehicle collisions

The association between acute medical illness and motor vehicle collisions (MVCs) among elderly emergency department patients is unclear. We sought to determine the prevalence of acute medical conditions that might impair driving ability among the elderly involved in MVCs and determine if there was an increased risk of the driver having an acute medical condition compared to similarly aged passengers.

We reviewed charts of patients aged 65 years or older whose emergency department visit was prompted by a motor vehicle collision between 1 July 2000 and 30 June 2010 at two Level 1 trauma centres. The exposure of interest was occupancy status (driver vs. passenger), and the outcome measure was the presence of any predefined acute medical illness that might impair driving ability.

Final analysis included 871 drivers (cases) and 307 passengers (controls). An acute medical illness was recorded in 107 patients (9%): 97 drivers (11%) and 10 passengers (3%). Compared to passengers, drivers had significantly higher odds of presenting with acute medical illness (OR 3.7, 95% CI 1.9-7.2). After controlling for potential confounders, the adjusted odds ratio was 5.5 (95% CI 2.3-13.0).

Acute medical conditions are a moderately common diagnosis among elderly drivers, presenting in about one in ten patients. A difference in the risk of finding an acute medical illness when comparing elderly drivers and passengers evaluated in the emergency department after a collision suggests the need for considering additional diagnostic investigation and post-discharge surveillance in this population.