Sleep Apnea More Than Doubles Car Accident Risk

Sleep apnea
Sleep apnea
Proper treatment with CPAP therapy effectively reduced the risk of motor vehicle accidents in people with sleep apnea.

Falling asleep behind the wheel is a scary reality for people with sleep apnea. The sleep breathing disorder is associated with a 2.5 times greater risk of motor vehicle accident, according to a study published in Sleep.

At least 25 million adults in the U.S. have sleep apnea, which is characterized by snoring and choking, gasping, or silent breathing pauses during sleep. Sleep disturbances can cause patients to get too little sleep, resulting in daytime sleepiness and use of sleeping pills.

Researchers from the University of Gothenburg in Sweden found that treatment of sleep apnea with CPAP therapy reduced motor vehicle accident risk by 70%.

The researchers compared 1,478 patients with sleep apnea with a mean age of 54 years (70% men) to a control group of 635,786 licensed drivers, 21,118 of which had at least one motor vehicle accident during the study period. Patients with sleep apnea were involved in 82 accidents during the study period, including 56 in the five years prior to diagnosis and 26 in the five years after diagnosis.

Excess accident risk was most prominent in elderly patients aged 65 to 80. Driving distance, Epworth Sleepiness Score, short habitual sleep time, and use of sleep hypnotics were all associated with an increased motor vehicle accident risk. CPAP use greater than or equal to four hours a night was associated with a reduction in accident risk (7.6 to 2.5 accidents/1,000 drivers/y).

Researchers believe that accident frequency may be even higher in other countries like the U.S., where the AAA Foundation for Traffic Safety estimates that drowsy driving causes 328,000 car accidents a year, 6,400 of which are fatal.

Researchers hope the data will motivate patients to see their doctor if they are showing signs of sleep apnea. 


  1. Karimi M. Sleep. 2015; doi:10.5665/sleep.4486.