Long-term cannabis use patterns in Canadian youth linked to risky driving
Youth who maintained consistently high cannabis use or increased their use from adolescence to young adulthood were more likely to engage in impaired driving compared to occasional users, decreasers, or abstainers.
Quick Facts
What This Study Found
Chronic cannabis users and those with increasing use patterns were more likely to engage in risky impaired driving behaviors. Frequency of cannabis use independently predicted impaired driving risk after controlling for age, sex, socioeconomic status, other substance use, and simultaneous substance use. Youth using cannabis more than once a week were also more likely to drink heavily and use alcohol simultaneously.
Key Numbers
10-year follow-up period (2003-2013). 6 biennial interviews. 5 user groups identified: chronic users, increasers, occasional users, decreasers, and abstainers. Cannabis use more than once a week associated with increased driving risk.
How They Did This
Longitudinal Victoria Healthy Youth Survey following youth biennially over 6 occasions across 10 years (2003-2013), examining the association between marijuana use trajectories and impaired driving risks.
Why This Research Matters
With cannabis legalization expanding, understanding which usage patterns predict driving risk can help target prevention efforts toward the highest-risk groups.
The Bigger Picture
This study moves beyond cross-sectional snapshots to show that the trajectory of cannabis use matters for driving risk, not just whether someone uses at a single point in time.
What This Study Doesn't Tell Us
Self-reported data. Single Canadian city (Victoria). Driving risk was self-reported, not measured through accident records or driving performance tests.
Questions This Raises
- ?Would targeted interventions for "increasers" during adolescence prevent later impaired driving?
- ?How do these patterns interact with cannabis potency changes over time?
Trust & Context
- Key Stat:
- 10-year follow-up across 6 time points
- Evidence Grade:
- Longitudinal design with multiple time points strengthens causal inference, though self-reported outcomes limit certainty.
- Study Age:
- 2019 study using data collected from 2003 to 2013.
- Original Title:
- Marijuana trajectories and associations with driving risk behaviors in Canadian youth.
- Published In:
- Traffic injury prevention, 20(5), 472-477 (2019)
- Authors:
- Sukhawathanakul, Paweena(2), Thompson, Kara(3), Brubacher, Jeff, Leadbeater, Bonnie
- Database ID:
- RTHC-02310
Evidence Hierarchy
Follows a group of people over time to track how outcomes develop.
What do these levels mean? →Frequently Asked Questions
Does cannabis use in teens predict impaired driving later?
This study found that teens who maintained consistently high use or increased their use into young adulthood were more likely to engage in impaired driving behaviors.
Is occasional cannabis use linked to driving risk?
Occasional users did not show the same elevated driving risk as chronic or increasing users in this study.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-02310APA
Sukhawathanakul, Paweena; Thompson, Kara; Brubacher, Jeff; Leadbeater, Bonnie. (2019). Marijuana trajectories and associations with driving risk behaviors in Canadian youth.. Traffic injury prevention, 20(5), 472-477. https://doi.org/10.1080/15389588.2019.1622097
MLA
Sukhawathanakul, Paweena, et al. "Marijuana trajectories and associations with driving risk behaviors in Canadian youth.." Traffic injury prevention, 2019. https://doi.org/10.1080/15389588.2019.1622097
RethinkTHC
RethinkTHC Research Database. "Marijuana trajectories and associations with driving risk be..." RTHC-02310. Retrieved from https://rethinkthc.com/research/sukhawathanakul-2019-marijuana-trajectories-and-associations
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.