Sleep habits and road traffic accident risk for Iranian occupational drivers.

OBJECTIVES The aim of this study is to assess the sleep quality and sleep disorders (prevalence of obstructive sleep apnea and sleepiness) among occupational drivers in Iran and to determine which demographic factors and occupational habits are linked to road traffic accidents. MATERIAL AND METHODS In this analytic cross-sectional study 556 occupational road drivers from Shahroud city (in the northeast of Iran) participated, upon a prior verbal informed consent, during 2013-2014. The Pittsburgh Sleep Quality Index (PSQI) standard questionnaire that scored on 7 point scale, the 8-item Epworth Sleepiness Scale (ESS) questionnaire and the 8-question STOP-Bang questionnaire along with demographic information and occupational data were used. To explore the independent factors associated with odds of poor sleep quality and road accident, multiple logistic regression models were used. RESULTS Prevalence of previous road accidents, sleepiness while driving, and obstructive sleep apnea scored ≥ 3 in the study, and drivers accounted for 23.8%, 29%, and 24.8%, respectively. The global mean score of sleep quality and excessive sleepiness score were 5.2 and 4.8, respectively. The main factors related to the odds of poor sleep quality were snoring (odds ratio (OR) = 2.34; 95% confidence interval (CI): 1.15-4.77), smoking (OR = 2.12; 95% CI: 1.15-3.97), and driving times in a day (OR = 1.12; 95% CI: 1.03-1.21). The Epworth Sleepiness Scale (OR = 1.13; 95% CI: 1.07-1.23) and suffering from apnea (OR = 4.89; 95% CI: 1.07-23.83) were the best predictors for odds (increased risk) of road accidents. CONCLUSIONS A considerable proportion of Iranian drivers had records of road accidents; poor sleep quality, sleepiness while driving, and sleep disorder breathing (obstructive sleep apnea - OSA). Snoring, smoking, driving time in a day, excessive sleepiness, and presumably apnea increase the odds of poor sleep quality and road traffic accident for Iranian occupational drivers.