Driving Under the Influence of Cannabis Held Steady From 2016-2020, Even as Cannabis Use Rose 29% | Research

The takeaway

Despite a 29% increase in past-year cannabis use from 2016 to 2020, cannabis-impaired driving among users actually decreased, while alcohol-impaired driving also continued to decline.

Anyone following cannabis policy debates, impaired driving researchers, public health officials in legalization states.

29% increase in cannabis use, but impaired driving among users went down

What the researchers found

Using nationally representative NSDUH data, over 1 in 10 US adults reported DUI of any substance annually. Cannabis-impaired driving did not increase in the general population, but among past-year cannabis users it decreased (AOR 0.95). Meanwhile, alcohol-impaired driving declined overall (AOR 0.96). Females and adults ages 26-34 and 65+ showed increasing trends for driving under the influence of non-cannabis drugs.

Why it matters

As cannabis legalization spreads, a key public health concern is whether more use translates to more impaired driving. This national data suggests the relationship is not straightforward: more people used cannabis, but the rate of driving impaired among users went down.

The numbers in context

Over 1 in 10 US adults reported past-year DUI of any substance. DUIA peaked at 8.7% in 2017 and declined (AOR 0.96). Past-year cannabis use rose 29.1%. DUIC among users declined (AOR 0.95).

How the study worked

Analysis of National Survey on Drug Use and Health data from 2016-2020, using nationally representative samples of non-institutionalized US adults. Prevalence estimates and adjusted logistic regressions characterized temporal trends overall and among demographic subpopulations.

What this study cannot tell us

Self-reported data likely underestimates actual DUI prevalence. The study period ends in 2020, so COVID-19 may have influenced driving patterns. Cannot distinguish between levels of impairment or crash risk.

How to read the evidence

Nationally representative data (NSDUH) with large sample sizes and adjusted analyses across multiple years.

When this study was published

Published 2023, using 2016-2020 data.

The bigger picture

These findings challenge the assumption that rising cannabis use automatically means more impaired driving. Possible explanations include growing public awareness campaigns, substitution of cannabis for alcohol in some contexts, or shifts in how and where people consume cannabis.

Questions still open

Why did cannabis-impaired driving decrease among users even as use increased?
Have legalization-era public awareness campaigns about impaired driving been effective?

Common questions

Did more cannabis use lead to more impaired driving?

No. While past-year cannabis use rose 29% from 2016 to 2020, the rate of driving under the influence of cannabis among users actually decreased.

How does cannabis-impaired driving compare to alcohol-impaired driving?

Alcohol-impaired driving was more prevalent overall (8.7% at peak) and also declined over the period. Cannabis-impaired driving was less common and held steady in the general population.

Read the original research

Driving under the influence of cannabis, alcohol, and illicit drugs among adults in the United States from 2016 to 2020.

Addictive behaviors, 140, 107614

View on PubMed ↗Publisher’s paper ↗

Citation

Myers, Matthew G; Bonar, Erin E; Bohnert, Kipling M. (2023). Driving under the influence of cannabis, alcohol, and illicit drugs among adults in the United States from 2016 to 2020.. Addictive behaviors, 140, 107614. https://doi.org/10.1016/j.addbeh.2023.107614