Exploring the relationship between early drinking patterns and vehicle control measures in driving simulation among sober young adults

Background: Among young drivers, drinking is a primary contributor to motor vehicle crashes. Drinking history metrics have been related to vehicle control among sober drivers. Younger drinking is associated with alcohol- and non-alcohol-related risky behaviors and neurocognitive vulnerabilities. Although early drinking translates to a health-risking profile (i.e., impaired driving, neurocognitive vulnerabilities), few studies have examined the relationship between early drinking initiation/patterns and sober young driver behavior. Objective: To explore the relationship between early drinking patterns and vehicle control among sober young adult drivers. Methods: Participants: U.S. licensed drivers (18-25-years-old) were recruited. Drinking Measures: Self-reported age of first: drink (AgeDrink), drunk (AgeDrunk), and 5 or more drinks (Age5Plus). Driving Simulation: Vehicle control measures were collected using a ½-cab miniSim® simulator and a scenario with straight and curved roadways, turns, and intersections: standard deviation (SD)/average steering wheel angle, SD lane position, minimum headway time/distance, and SD/minimum/maximum speed. Results: Data from 18 participants were included. All measures were inversely related to lane position on straight roads; average steering wheel angle on curved roads; average steering wheel angle while turning, and positively related to SD steering wheel angle on curved roads and while turning. AgeDrink and AgeDrunk were inversely related to minimum headway time/distance on curved roads. AgeDrunk and Age5Plus were inversely related to SD speed through intersections. AgeDrink and Age5Plus were inversely related to maximum speed through intersections. AgeDrink was inversely related to SD steering wheel angle on straight roads and SD lane position through intersections. Conclusions: Our findings offer an initial perspective on how, even while sober, drinking at a younger age is associated with greater variability in vehicle control measures that are linked to increased crash-risk. These findings point to a need to broaden our understanding of how youth drinking may relate to sober driving performance and potentially heighten crash risk.