Monday, February 12, 2018
The title of this post is the title of this notable new "Research Letter" authored by John Staples and Donald Redelmeier published in JAMA Internal Medicine. Here is how the publication starts and ends:
On April 20 each year, thousands of Americans celebrate the intoxicating properties of marijuana on a popular counterculture holiday known as “4/20.” Legal marijuana sales surge in anticipation of the “High Holiday,” and college students report increased cannabis consumption on 4/20 itself. In many cities, activists and enthusiasts gather at public celebrations that feature synchronized mass consumption of cannabis at 4:20 pm.
Driving simulation studies indicate that higher blood Δ9-tetrahydrocannabinol concentrations decrease reaction times and increase variability in speed and lane position, while some epidemiologic studies suggest that acute cannabis intoxication increases crash risk. Despite this evidence, driving after cannabis consumption is surprisingly common. We hypothesized that the April 20 cannabis celebration might be associated with a population-level increase in the risk of fatal traffic crash involvement....
We examined a quarter-century of national data and found a 12% increase in the relative risk of a fatal traffic crash after 4:20 pm on April 20 compared with identical time intervals on control days. Although the vast majority of Americans do not celebrate 4/20, the observed association was comparable in magnitude to the increase in traffic risks observed on Superbowl Sunday. Policy makers may wish to consider these risks when liberalizing marijuana laws, paying particular attention to regulatory and enforcement strategies to curtail drugged driving.