Obstructive sleep apnea and road traffic accidents: a Danish nationwide cohort study

In this nationwide study, we investigate the risk and severity of all road traffic accidents in patients with obstructive sleep apnea (OSA). We used the unique Danish registries to identify all Danish citizens receiving a diagnosis of OSA between 1995 and 2015. As a reference cohort, we randomly selected 10 sex- and age-matched citizens for each patient. We used Poisson regression to calculate the incidens rate ratio (IRR) for all road traffic accidents (motor vehicle, bicycle, and pedestrian) in both groups, and Cox proportional regression analysis to compare risk of first motor vehicle accident. Lastly, we used Fischers’ Exact test to compare severity of motor vehicle accident between the two groups- We identified 48,168 patients with OSA, covering up to 24 years of follow-up. Patients with OSA had an increased risk of road traffic accidents when compared with the reference cohort (hazard ratio, 1.15; 95% CI, 1.10–1.20; IRR: 1.19; 95% CI, 1.14–1.29), especially motor vehicle accidents (hazard ratio, 1.29; 95% CI, 1.18–1.39; IRR 1.30; 95% CI, 1.20–1.42). The risk of accidents as pedestrian or bicyclist were not increased. Further, patients with OSA had a tendency to be involved in more severe motor vehicle accidents. This is the first nationwide study to estimate the risk of all road traffic accidents in patients with OSA. Our estimates show that patients with OSA have an increased risk of motor vehicle accidents, and greater severity of accidents, when compared with a large reference cohort. •First nationwide study to estimate the risk of all road traffic accidents in patients with OSA.•The risk of motor vehicle accidents is significantly increased in patients with OSA.•Accidents are more severe among patients with OSA than matched references.•Patients with OSA's risk of accidents was not increased while biking or as a pedestrian.