Associations of cannabis use with motor vehicle crashes and traffic stops among older drivers: AAA LongROAD study

Abstract

Background

Acute cannabis use is associated with a higher risk of motor vehicle crashes (MVC). This study aimed to determine if self-reported past-year cannabis use is associated with MVC or traffic stops among older drivers.

Methods

This cross-sectional analysis used data from a multi-center study enrolling active drivers aged 65-79 years. Data regarding cannabis use, MVC, and traffic stops (i.e., being pulled over by police, whether ticketed or not) within the previous 12 months were collected through participant interviews. Log-binomial regression models examined associations of past-year cannabis use with MVC and traffic stops, adjusting for site and sociodemographic and mental health characteristics.

Results

Of 2,095 participating older drivers, 186 (8.88%) used cannabis in the past year but only 10 (<0.5%) within an hour before driving in the last 30 days; 11.41% reported an MVC and 9.45% reported a traffic stop. Past-year cannabis users had a higher prevalence of MVC (adjusted prevalence ratio [aPR] = 1.38; 95%CI: 0.96, 2.00; p = 0.086) and traffic stops (aPR = 1.58; 1.06, 2.35; p = 0.024).

Conclusions

Past-year cannabis use was associated with increased traffic stops, which are correlated modestly with increased MVC in past studies and may indicate impaired driving performance. We did not find a statistically significant association of past-year cannabis use with MVC, which may indicate limited sustained effects on driving performance from periodic use among older adults, who report rarely driving immediately after use.

Keywords:

• Older drivers
• cannabis
• driving
• traffic stops
• motor vehicle crashes

Acknowledgements

The LongROAD Research Team also includes Howard Andrews, David LeBlanc, Lindsay Ryan, and Robert Santos.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the AAA Foundation for Traffic Safety (Washington, DC), with additional support for REDCap from NIH/NCATS Colorado CTSA Grant Number UL1 TR002535. This research was also supported in part by Grant Number 1 R49 CE002096 from the Centers for Disease Control and Prevention (CDC) to the Center for Injury Epidemiology and Prevention at Columbia University. The AAA Foundation for Traffic Safety, USA, contributed to the design and methods of the LongROAD study and reviewed a draft manuscript. The lead author (CGD) made the decision to submit the manuscript for publication. The report’s findings and conclusions are solely those of the authors and do not necessarily reflect the official position of the AAA Foundation for Traffic Safety, the CDC or the NIH.