Sleep apnea symptoms and accident risk factors in Persian commercial vehicle drivers

Motor vehicle accidents are the second highest cause of mortality in Iran. Sleep apnea symptoms have been associated with increased risk of motor vehicle accidents in other countries. However, we have limited data in Iran. We conducted a study to evaluate sleep apnea symptoms and sleepiness in professional drivers and to assess the predictors of motor vehicle accidents in Iran. A questionnaire-based cross-sectional study of drivers was done in Shahrekord, Iran. This study used a self-administered questionnaire that included personal information, the Epworth sleepiness scale (ESS), the Berlin questionnaire, and history of previous automobile accidents. Nine hundred thirty-one male drivers (62% of invited drivers), aged 40.2 +/- 10.1 years (mean +/- SD), were included in the study. The mean number of hours spent driving was 48.9 h/week. The median distance covered weekly was 2,905 km/week. Statistical analysis included logistic models with covariate-adjusted P values of < 0.01 s (odds ratios and 95% confidence intervals or limits). Independent accident predictors were sought. The professional drivers with car accidents had a higher risk in Berlin questionnaire (P < 0.02), a larger mean neck circumference (P < 0.04), and more witnessed apneas (P < 0.04). There was no significant association between in drivers with car accident and ESS above 10. In Persian professional drivers, high-risk Berlin questionnaire, larger neck circumference, and a history of witnessed apneas were the most important predictors of motor vehicle accident.