RT Journal Article
SR Electronic
T1 Emergency department visits during the 4/20 cannabis celebration
JF Emergency Medicine Journal
JO Emerg Med J
FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine
SP 187
OP 192
DO 10.1136/emermed-2019-208947
VO 37
IS 4
A1 Staples, John A
A1 Merchant, Ketki
A1 Erdelyi, Shannon
A1 Lund, Adam
A1 Brubacher, Jeffrey R
YR 2020
UL http://emj.bmj.com/content/37/4/187.abstract
AB Background Annual ‘4/20’ cannabis festivals occur around the world on April 20 and often feature synchronised consumption of cannabis at 4:20 pm. The relationship between these events and demand for emergency medical services has not been systematically studied.Methods We conducted a population-based retrospective cohort study in Vancouver, Canada, using 10 consecutive years of data (2009–2018) from six regional hospitals. The number of emergency department (ED) visits between 4:20 pm and 11:59 pm on April 20 were compared with the number of visits during identical time intervals on control days 1 week earlier and 1 week later (ie, April 13 and April 27) using negative binomial regression.Results A total of 3468 ED visits occurred on April 20 and 6524 ED visits occurred on control days. A non-significant increase in all-cause ED visits was observed on April 20 (adjusted relative risk: 1.06; 95% CI 1.00 to 1.12). April 20 was associated with a significant increase in ED visits among prespecified subgroups including a 5-fold increase in visits for substance misuse and a 10-fold increase in visits for intoxication. The hospital closest to the festival site experienced a clinically and statistically significant 17% (95% CI 5.1% to 29.6%) relative increase in ED visits on April 20 compared with control days.Interpretation Substance use at annual ‘4/20’ festivals may be associated with an increase in ED visits among key subgroups and at nearby hospitals. These findings may inform harm reduction initiatives and festival medical care service planning.