Sleep-impaired emotional regulation, impaired cognition, and poor sleep health are associated with risky sleepy driving in young adults.

Driving during young adulthood is a time of increased crash risk. Many factors (e.g., driving experience, aggression) contribute to the increased risk, but factors associated with daytime sleepiness and sleep health may also contribute. The current study examined the relationships between experiences of sleepiness, sleep timing and stability, sleep-impaired emotional regulation, and sleep-impaired cognition among younger persons engaging in 2 risky sleepy driving behaviors: Continuing to drive while sleepy and having experienced a sleep-related close call. The study was advertised in the Queensland University of Technology's online environment and 137 young adults (58.39% women) aged 18 to 25 years completed an anonymous online questionnaire assessing aspects related to daytime sleepiness, sleep timing and stability, sleep-impaired emotional regulation, and sleep-impaired cognition. In total, 15.38% of the participants reported that they had experienced a sleep-related close call. The main outcomes were that both age and the sleep-impaired emotional regulation variable were associated with the outcome variables. The study variables accounted for 18.94% of the variance in continuing to drive while sleepy, and the same variables accounted for 42.69% of the variance (Nagelkerke's statistic) in having had a sleep-related close call. Shorter sleep durations and greater levels of sleep-impaired cognition were significantly associated with having a sleep-related close call. Different variables were associated with the 2 risky driving behaviors, suggesting different underlying factors. Sleep-impaired emotional regulation and/or sleep-impaired cognition could be used to signal drivers that they are impaired by sleepiness.