Sleep Apnea Doubles Car Crash Risk, Study Shows

Published online in the journal Thorax, the study also found that patients with sleep apnea are three to five times more likely to be in a serious car crash involving personal injury.

Using data from the Insurance Corporation of British Columbia, researchers studied nearly 1,600 people including patients with and without sleep apnea.

"We were startled by the number of crashes, but even more surprised about the severity of the crashes and how many involved personal injury,” said study author Dr. Najib Ayas of the Vancouver Coastal Health Sleep Disorders Program and Associate Professor of Medicine at UBC. “Even those patients with fairly mild sleep apnea had an increased risk of serious crashes.”

Previous studies have identified a link between sleep apnea and increased risk for car crashes, but this is the largest study of its kind and the first study to examine the severity of such crashes.

Sleep apnea causes excessive daytime sleepiness. However in the study the patients' self-reported sleepiness was not linked to an increased risk of crashes. “The study suggests that the patients may not be aware of the potential driving hazards caused by sleep apnea,” said Dr. John Fleetham, UBC Professor of Medicine and a co-author of the study. “Given the markedly increased risk of crashes in patients with sleep apnea, we feel it is important for people with suspected sleep apnea to be assessed for this common disorder for which there are several effective treatments.”

Among the general population, men have more car crashes than women. However, men and women with sleep apnea in this study had similar crash rates.