Objectives Non-medical cannabis recently became legal for adults in Canada. Legalization provides opportunity to investigate the public health effects of national cannabis legalization on presentations to emergency departments (EDs). Our study aimed to explore association between cannabis-related ED presentations, poison control and telemedicine calls, and cannabis legalization. Methods Data were collected from the National Ambulatory Care Reporting System from October 1, 2013, to July 31, 2019, for 14 urban Alberta EDs, from Alberta poison control, and from HealthLink, a public telehealth service covering all of Alberta. Visitation data were obtained to compare pre- and post-legalization periods. An interrupted time-series analysis accounting for existing trends was completed, in addition to the incidence rate ratio (IRR) and relative risk calculation (to evaluate changes in co-diagnoses). Results Although only 3 of every 1,000 ED visits within the time period were attributed to cannabis, the number of cannabis-related ED presentations increased post-legalization by 3.1 (range -11.5 to 12.6) visits per ED per month (IRR 1.45, 95% confidence interval [CI]; 1.39, 1.51; absolute level change: 43.5 visits per month, 95% CI; 26.5, 60.4). Cannabis-related calls to poison control also increased (IRR 1.87, 95% CI; 1.55, 2.37; absolute level change: 4.0 calls per month, 95% CI; 0.1, 7.9). Lastly, we observed increases in cannabis-related hyperemesis, unintentional ingestion, and individuals leaving the ED pre-treatment. We also observed a decrease in co-ingestant use. Conclusion Overall, Canadian cannabis legalization was associated with small increases in urban Alberta cannabis-related ED visits and calls to a poison control centre.

Background: On October 17th, 2018, non-medical cannabis became legal to adults for the first time in Canada. This has created a previously unseen opportunity to investigate the effects of recreational cannabis legalization in a developed country, particularly on strained Emergency Departments (EDs). Secondly, reports within the United States have suggested state-level legalization of cannabis, both recreationally and medically, has resulted in a decrease of opiate-related presentations. Given the pressure of the opiate crisis on healthcare resources, we sought to examine if this trend was present in Alberta. Objectives: The current study aims to identify if presentation patterns in adult and pediatric populations have changed when comparing pre- and post-legalization periods, and if rural-urban disparities exist. We also aim to identify if the legalization of cannabis is correlated with a reduction in opiate-related ED presentations. Lastly, we aimed to address the aforementioned objectives in the context of telehealth by examining calls to poison control and HealthLink within Alberta. Methods: Retrospective data was collected from the National Ambulatory Care Reporting System, HealthLink, and Poison and Drug Information Service. Extraction is currently in progress, and we expect to include 20 000 records and 12 000 calls. An interrupted time-series analysis will be completed, allowing for a comparison of trends pre- and post-legalization. Participants have been identified based on International Disease Classifications for cannabis and opiate-related injury. Commonly reported injuries will be clustered to identify changes in injury patterns. Data was collected from October 1st 2013 up to May 31st, 2019 for all EDs within Alberta. Results: Preliminary results suggest the legalization of cannabis initially led to a dramatic increase in ED presentations, followed by a return to pre-legalization volume. HealthLink data suggests a different trend, with steadily increasing calls in the months prior to legalization, followed by stabilization. Cannabis legalization is also correlated with a decrease in post-legalization opiate-related calls (r=-0.51, p=0.01). Conclusion: Overall, national legalization of cannabis appears to be responsible for a short period of increased ED usage, but does not appear to have long-lasting effects on healthcare resource utilization. Differences are apparent between telehealth service and ED use.

Introduction: Non-medical cannabis recently became legal on October 18th, 2018 to Canadian adults. The impact of legalization on Emergency Departments (EDs) has been identified as a major concern. The study objective was to identify changes in cannabis-related ED visits and changes in co-existing diagnoses associated with cannabis-related ED visits pre- and post-legalization for the entire urban population of Alberta. Urban Alberta was defined as Calgary and Edmonton, inclusive of Sherwood Park and St. Albert given the proximity of some Edmontonians to their EDs) encompassing 12 adult EDs and 2 pediatric EDs. Methods: Retrospective data was collected from the National Ambulatory Care Reporting System, and from the HealthLink and the Alberta Poison and Drug Information Service (PADIS) public telehealth call databases. An interrupted time-series analysis was completed via segmented regression calculation in addition to incident rate and relative risk ratio calculation for the pre- and post-legalization periods to identify both differences among the entire urban Alberta population and differences among individuals presenting to the ED. Data was collected from October 1st, 2013 up to July 31st, 2019 for ED visits and was adjusted for natural population increase using quarterly reports from the Government of Alberta. Results: The sample included 11 770 pre-legalization cannabis-related visits, and 2962 post-legalization visits. Volumes of ED visits for cannabis-related harms were found to increase post-legalization within urban EDs (IRR 1.45, 95% CI 1.39, 1.51; absolute level change: 43.48 visits per month in urban Alberta, 95% CI 26.52, 60.43), and for PADIS calls (IRR 1.87, 95% CI 1.55, 2.37; absolute level change: 4.02 calls per month in Alberta, 95% CI 0.11, 7.94). The increase in visits to EDs equates to an increase of 2.72 visits per month, per ED. Lastly, increases were observed for cannabinoid hyperemesis (RR 1.23, 95% CI 1.10, 1.36), unintentional ingestion (RR 1.48, 95% CI 1.34, 1.62), and in individuals leaving the ED pre-treatment (RR 1.28, 95% CI 1.08, 1.49). Decreases were observed for coingestant use (RR 0.77, 95% CI 0.73, 0.81) and hospital admissions (RR 0.88, 95% CI 0.80, 0.96). Conclusion: Overall, national legalization of cannabis appears to be correlated with a small increase in cannabis-related ED visits and poison control calls. Post-legalization, fewer patients are being admitted, though cannabinoid hyperemesis appears to be on the rise.