Sleep Variability in UK Long Distance Heavy Goods Vehicle Drivers

Objectives Sleep variability levels are unknown in heavy goods vehicle (HGV) drivers yet are associated with adverse health outcomes and reduced driver vigilance when high. Methods Two hundred and thirty-three HGV drivers recruited across 25 UK depots provided sleep variability, sleep duration, and sleep efficiency data via wrist-worn accelerometry (GENEActiv) over 8 days. Sleep variability indicators included social jetlag (the difference in midpoint of the sleep window between work and nonworkdays) and intraindividual variability of sleep window onset time, out-of-bed time, and sleep duration. Results Fifty-three percent of drivers experienced social jetlag (≥1 hour), and 27% experienced high (>2 hours) social jetlag. Drivers with the highest sleep variability had the shortest sleep duration and lowest sleep efficiency during workdays. Conclusions Drivers with high sleep variability may experience more fatigue when driving given the poor sleep outcomes during workdays observed.