Risk Factors Associated With Driving After Cannabis Use Among Canadian Young Adults

• Date: 01 April 2022
• DOI: 10.1177/00220426211049359
• Published date: 01 April 2022
• Subject Matter: Articles

Article

Journal of Drug Issues

2022, Vol. 52(2) 144–167

© The Author(s) 2021

Article reuse guidelines:

sagepub.com/journals-permissions

DOI: 10.1177/00220426211049359

journals.sagepub.com/home/jod

Risk Factors Associated With

Driving After Cannabis Use

Among Canadian Young Adults

Christophe Hu`

ynh

1,2,4

, Alexis Beaulieu-Thibodeau

1,3

,

Jean-S´

ebastien Fallu

1,4,5

, Jacques Bergeron

1,3

,

Jorge Flores-Aranda

1,6

, Alain Jacques

7

, and Serge Brochu

1,8

Abstract

This study identif‌id the most prominent risk factors associated with driving after cannabis use

(DACU). 1,126 Canadian drivers (17–35 years old) who have used cannabis in the past 12 months

completed an online questionnaire about sociodemographic information, substance use habits,

cannabis effect expectancies, driving behaviours and peers’behaviours and attitudes concerning

DACU. A hierarchical logistic regression allowed identifying variables that were associate d with

DACU. Income (CA$30,000–CA$69,000), weekly-to-daily cannabis use, higher level of cannabis-

related problems, expectation that cannabis facilitates social interactions, drunk driving, belief that

DACU is safe, general risky driving behaviours, having a few friends who had DACU and injunctive

norms predicted past 12-month DACU. Older age, holding negative expectations concerning

cannabis, driving aggressively and perceived accessibility of public transportation decreased the

probability of DACU. With restricted resources, programmes will be more eff‌icient by targeting

Canadian young adults most inclined to DACU by focussing on these risk factors.

Keywords

cannabis, driving under the inf‌luence, automobile driving, risk factors, risk-taking, Canada

1

University Institute on Addictions, CIUSSS Centre-Sud-de-l’

ˆ

Ile-de-Montr´

eal, Montr´

eal, Qu´

ebec, Canada

2

Department of Psychiatry and Addiction, Universit´

e de Montr´

eal, Montr´

eal, QC, Canada

3

Department of Psychology, Universit´

e de Montr´

eal, Montr´

eal, QC, Canada

4

School of Psychoeducation, Universit´

e de Montr´

eal, Montr´

eal, QC, Canada

5

Centre for Public Health Research, Universit´

e de Montr´

eal and CIUSSS Centre-Sud-de-l’

ˆ

Ile-de-Montr´

eal, Montr´

eal, QC,

Canada

6

School of Social Work, Universit´

eduQu

´

ebec `

a Montr´

eal, Montr´

eal, QC, Canada

7

Program to Assess and Reduce the Risk of Impaired Driving, CIUSSS Centre-Sud-de-l’

ˆ

Ile-de-Montr´

eal, Montr´

eal, QC,

Canada

8

School of Criminology, Universit´

e de Montr´

eal, Montr´

eal, QC, Canada

Corresponding Author:

Christophe Hu`

ynh, PhD, University Institute on Addictions, Centre int´

egr´

e universitaire de sant´

e et des services sociaux

du Centre-Sud-de-l’

ˆ

Ile-de-Montr´

eal, 950 rue de Louvain Est, Montreal, QC H2M 2E8, Canada.

Email: christophe.huynh.ccsmtl@ssss.gouv.qc.ca

Introduction

DACU (driving after cannabis use) is not uncommon in Canada. According to self-reported

surveys, before cannabis legalization, 39% of Canadian cannabis users declared driving within

2 hours after using cannabis in the past 12 months (Health Canada, 2019). After cannabis le-

galization, this rate dropped to 26% in 2019 and to 22% in 2020 (Health Canada, 2020). Previous

studies have highlighted that recent cannabis use decreases the cognitive and psychomotor

abilities required for driving such as reaction time, motor coordination, time perception, con-

centration, short-term memory and shared attention (Bondallaz et al., 2016;Capler, Bilsker, Van

Pelt, & MacPherson, 2017;Doroudgar et al., 2018;Hartman & Huestis, 2013;Mikulskaya &

Martin, 2018a;2018b;Rogeberg & Elvik, 2016). Regardless of age, sex and history of mis-

conduct, the presence of THC (delta-9-tetrahydrocannabinol), the main psychoactive molecule in

cannabis, in the blood was associated with a greater likelihood of collisions (Asbridge, Hayden, &

Cartwright, 2012;B´

edard, Dubois, & Weaver, 2007). Between 2003 and 2013, administrative

databases concerning motor vehicle collisions in Ontario show that 5.1% of collisions involved a

driver who tested positive for THC in the blood (B´

edard et al., 2007). In 2012, it was estimated that

75 Canadians died in a road accident involving cannabis and 4,407 were physically injured,

representing CA$1.09 billion in f‌inancial costs (Wettlaufer et al., 2017).

Previous studies have identif‌ied different sets of risk factors associated with DACU. Con-

cerning sociodemographic characteristics, DACU is more common among individuals under

35 years old (Domingo-Salvany et al., 2017;Voas, Lacey, Jones, Scherer, & Compton, 2013).

Recent cannabis users aged 18–24 constitute the age group who is the most ‘open’to the idea of

DACU (Davis et al., 2016). Although some studies report a higher proportion of males being

implicated in DACU (Arterberry et al., 2013;Voas et al., 2013), others do not f‌ind an association

between being male and DACU (Aston, Merrill, McCarthy, & Metrik, 2016;Domingo-Salvany

et al., 2017). There were no discernible patterns in methodology (i.e. DACU def‌inition oper-

ationalization, sample characteristics, variables included in regression models) to explain this

divergence. While Davis et al. (2016) found that American adults in the general population with a

lesser level of education or who had a job had a higher probability of DACU, these f‌indings were

not reported in specif‌ic samples such as high school students (Minaker et al., 2017;O’Malley &

Johnston, 2013;Wilson et al., 2018) or adults who drive on weekend evenings (Voas et al., 2013).

Characteristics related to cannabis use are associated with an increased likelihood of DACU,

such as frequency (Arterberry et al., 2013;Arterberry, Treloar, & McCarthy, 2017;Berg et al.,

2018;Borodovsky et al., 2020;Cuttler, Sexton, & Mischley, 2018;Matthews, Bruno, Dietze,

Butler, & Burns, 2014;Sukhawathanakul, Thompson, Brubacher, & Leadbeater, 2019;Whitehill,

Rodriguez-Monguio, Doucette, & Flom, 2019), greater quantity consumed within a given time

frame (Cuttler et al., 2018;Davis et al., 2016;Le Strat, Dubertret, & Le Foll, 2015) and presence of

cannabis-related problems or disorders (Choi, DiNitto, & Marti, 2019;Cook, Shank, Bruno,

Turner, & Mann, 2017;Le Strat et al., 2015;Scherer, Voas, & Furr-Holden, 2013). While some

studies suggest that alcohol users holding positive expectations regarding drinking are more likely

to be driving under the inf‌luence of alcohol, the relationship is less clear between expectations of

cannabis effects among cannabis users and DACU. Notably, the three previous studies on this

specif‌ic association report divergent results, probably due to differences in sample characteristics

(i.e. regarding cannabis use frequency and age grouping). As such, Arterberry et al. (2013) found

that negative expectations of cannabis effects were associated with a decreased likelihood of

DACU among college students who had used cannabis at least once in their lifetime, while Ewing

et al. (2015) reported that holding previously positive expectations concerning cannabis at ages 12

and 14 increased the likelihood of subsequent DACU among 16-year-old adolescents. Only 3.1%

of the 12-year-old sample participants had used cannabis in the previous month; this rate increased

Hu`

ynh et al. 145