Sleepiness and sleep-related accidents in commercial bus drivers

Professional drivers are at high risk of sleepiness due to a combination of factors including shift work and obstructive sleep apnea/hypopnea syndrome (OSAHS), and sleepiness in professional drivers is highly dangerous. This study aimed to determine the prevalence of excessive daytime sleepiness and accident rates in bus drivers.

Drivers employed at bus depots within 30 miles of Edinburgh were given a sleep questionnaire. One thousand eight hundred fifty-four drivers were approached, and 677 (37%; 25 female) completed questionnaires with a 97% response rate among the 456 given directly to drivers by the researcher.

Of the responding drivers, 133 (20% of total, 19% of researcher-delivered questionnaires) reported an Epworth sleepiness score > 10. Eight percent of drivers reported falling asleep at the wheel at least once/month, and 7% having an accident, and 18% a near-miss accident due to sleepiness while working.

This study shows a concerningly high rate of sleepiness and sleep-related accidents among bus drivers. Screening for OSAHS among commercial drivers needs to be seriously evaluated with some urgency.