Problematic substance use and implications for road safety: An investigation on psychological dysfunction and risky driving styles

Abstract

Problematic alcohol and cannabis use has been linked with psychological dysfunction and engagement in risky behaviour. This study aimed to investigate the relationships between alcohol and cannabis use patterns with self-regulatory dysfunction (i.e., worry; anger rumination; mindlessness; impulsivity), psychopathology (i.e., anxiety; depression; anger), and risky driving styles (i.e., anxious; dissociative; angry; reckless driving). An online survey was administered to three unique samples (n = 200 each) of Australian adults: frequent alcohol users, frequent cannabis users, and non-frequent substance users (i.e., the control group). Eligible participants did not use any other substance more than once per month. Comparative analysis (MANOVA) showed that frequent cannabis users had the highest self-reported psychological dysfunctioning and risky driving styles, followed by frequent alcohol users, and then the control group. Bivariate correlations revealed that most prominently, the severity of substance dependency and the frequency of driving under the influence (DUI) of alcohol and cannabis were positively related to specific forms of psychological dysfunctioning and risky driving styles. Such findings highlight the potential relevance of both chronic and acute influences on driving behaviour. Finally, four separate path analyses were implemented which predicted specific risky driving styles (e.g., anxious driving), with substance use dependency as the moderator, and the corresponding self-regulatory dysfunction (e.g., worry) and psychopathology (e.g., anxiety) variables as mediators. The results suggested that substance use dependency indirectly affected risky driving styles, through its influence on specific self-regulatory dysfunction, and psychopathology, whilst controlling for the effects of DUI. Together these findings highlight the increased road safety risks associated with problematic alcohol and cannabis use, outside of acute-related influences.