Sleepiness and sleep-disordered breathing in truck drivers : risk analysis of road accidents.

Background: Portugal has one of the highest road traffic fatality rates in Europe. A clear association between sleep-disordered breathing (SDB) and traffic accidents has been previously demonstrated. This study aimed to determine prevalence of excessive daytime sleepiness (EDS) and other sleep disorder symptoms among truck drivers and to identify which individual traits and work habits are associated to increased sleepiness and accident risk.

Methods: We evaluated a sample of 714 truck drivers using a questionnaire (244 face-to-face interviews, 470 self-administered) that included sociodemographic data, personal habits, previous accidents, Epworth Sleepiness Scale (ESS), and the Berlin questionnaire (BQ).

Results: Twenty percent of drivers had EDS and 29 % were at high risk for having obstructive sleep apnea syndrome (OSAS). Two hundred sixty-one drivers (36.6 %) reported near-miss accidents (42.5 % sleep related) and 264 (37.0 %), a driving accident (16.3 % sleep related). ESS score ≥ 11 was a risk factor for both near-miss accidents (odds ratio (OR)=3.84, p<0.01) and accidents (OR=2.25, p<0.01). Antidepressant use was related to accidents (OR=3.30, p=0.03). We found an association between high Mallampati score (III-IV) and near misses (OR=1.89, p=0.04).

Conclusion: In this sample of Portuguese truck drivers, we observed a high prevalence of EDS and other sleep disorder symptoms. Accident risk was related to sleepiness and antidepressant use. Identifying drivers at risk for OSAS should be a major priority of medical assessment centers, as a public safety policy.