Impact Of Legalization Research Articles

Examining the Potential Impact of Recreational Cannabis Legalization on Individuals Receiving Treatment for Substance Use Disorder: An Interrupted Time Series Study in Guelph, Ontario, Canada

Objective: The present research evaluated the impact of legalizing recreational cannabis among individuals with substance use disorders (SUDs) who may already use cannabis at high rates. Method: Using an interrupted time series study design, we evaluated the potential impact of legalizing recreational cannabis among individuals seeking treatment for SUD within a hospital-based treatment setting in Guelph, Ontario. We examined 2,925 individuals who entered an inpatient SUD treatment program between April 2017 and December 2021. We performed segmented regression analyses using both the date of cannabis legalization and the date of edibles legalization as the interruption time point. We also performed stratified analyses to examine potential sex differences. Results: We found no significant changes in the frequency of cannabis use using either of the interruption time points. However, among the subsample who had used cannabis, there was evidence of increasing CUD severity post-legalization of edibles, as well as an overall decreasing trend in readiness to quit over time. Stratified analyses also suggested possible sex differences in frequency of cannabis use, CUD severity, and readiness to quit. Conclusions: Results point to some small but potentially important impacts of recreational cannabis legalization that may only continue with time. Nevertheless, there is a need to continue to monitor cannabis use trends over time to understand any potential lagged effects.

The impact of recreational cannabis legalization on cannabis-related acute care events among adults with schizophrenia.

Patients with schizophrenia have a higher risk of cannabis use disorder and may be uniquely affected by the legalization of recreational cannabis. This study examined whether cannabis legalization led to changes in acute care utilization among patients with schizophrenia. Using linked health administrative data, we included adult patients with schizophrenia in Ontario from October 2015 to May 2021 (n = 121,061). We examined the differences in cannabis, psychosis, and mental health-related emergency department (ED) visits over three periods: pre-legalization, legalization of flowers and herbs (phase 1), and legalization of edibles, extracts, and topicals (phase 2) using interrupted time-series methods. Our study found that phase 1 was associated with decreases in cannabis-related, mental health-related, and cannabis + psychosis-related ED visits among the patients with schizophrenia. Notably, an immediate 25.8% (95% CI 13.8-37.6%) decrease in cannabis-related ED visits was observed in men, and an immediate 18.5% decrease in mental health-related ED visits (95% CI 6.0-31.2%) in women. These decreases were also shown in the comparative ITS models, demonstrating that the changes observed were distinct from trends in the general population. However, phase 2 was not associated with any significant changes. Despite higher baseline rates of acute care utilization among patients with schizophrenia, cannabis legalization was associated with significant reductions, particularly during phase 1. Our findings suggest that regulatory measures accompanying legalization could enhance the quality and safety of cannabis products, potentially leading to fewer adverse health outcomes in vulnerable patient populations. Further research is needed to optimize healthcare responses for this vulnerable population.

Changes in Cannabis Use Patterns in Psychiatric Populations Pre- and Post-Legalization of Recreational Cannabis Use in Canada: A Repeated Cross-Sectional Survey

Objective: Since the federal Canadian government legalized cannabis in 2018, cannabis use in the general population has slightly increased. However, little is known about the impact of cannabis legalization on pattens of cannabis use in psychiatric populations. Method: We studied changes in daily/almost daily and average 30-day cannabis use amongst individuals currently using cannabis who reported past 12-month experiences of specific mental health disorders and among those without past 12-month experiences of any mental health disorder before and after Canadian legalization of recreational cannabis use (N = 13,527). Data came from Canadian respondents in Wave 1 (August–October 2018), Wave 2 (September–October 2019), and Wave 3 (September–November 2020) of the International Cannabis Policy Study (ICPS). Results: After adjustment for covariates, among individuals currently using cannabis, the odds of using cannabis daily/almost daily increased only in individuals with schizophrenia between Wave 1 and Waves 3 (aOR = 9.19, 95% CI: 2.46 – 34.37). Similarly, significant increases in average 30-day cannabis use between Wave 1 (M = 12.80, SE = 1.65) and Wave 3 (M = 18.07, SE = 1.03) were observed only among individuals with schizophrenia [F (1,2) = 4.58, p < .05). No significant changes in daily/almost daily or average past 30-day cannabis use were observed in those without mental health problems or those reporting anxiety, depression, PTSD, bipolar disorder, or substance use disorders. Conclusions: Since legalization, cannabis use has significantly increased only among people with schizophrenia, highlighting the need for targeted public health prevention programs.

Road hazard: a systematic review of traffic injuries following recreational cannabis legalization.

Acute cannabis use is associated with impaired driving performance and increased risk of motor vehicle crashes. Following the Canadian Cannabis Act's implementation, it is essential to understand how recreational cannabis legalization impacts traffic injuries, with a particular emphasis on Canadian emergency departments. This study aims to assess the impact of recreational cannabis legalization on traffic-related emergency department visits and hospitalizations in the broader context of North America. A systematic review was conducted according to best practices and reported using PRISMA 2020 guidelines. The protocol was registered on July 5, 2022 (PROSPERO CRD42022342126). MEDLINE(R) ALL (OvidSP), Embase (OvidSP), CINAHL (EBSCOHost), and Scopus were searched without language or date restrictions up to October 12, 2023. Studies were included if they examined cannabis-related traffic-injury emergency department visits and hospitalizations before and after recreational cannabis legalization. The risk of bias was assessed. Meta-analysis was not possible due to heterogeneity. Seven studies were eligible for the analysis. All studies were conducted between 2019 and 2023 in Canada and the United States. We found mixed results regarding the impact of recreational cannabis legalization on emergency department visits for traffic injuries. Four of the studies included reported increases in traffic injuries after legalization, while the remaining three studies found no significant change. There was a moderate overall risk of bias among the studies included. This systematic review highlights the complexity of assessing the impact of recreational cannabis legalization on traffic injuries. Our findings show a varied impact on emergency department visits and hospitalizations across North America. This underlines the importance of Canadian emergency physicians staying informed about regional cannabis policies. Training on identifying and treating cannabis-related impairments should be incorporated into standard protocols to enhance response effectiveness and patient safety in light of evolving cannabis legislation.

Immigrant legalization and the redistribution of state funds: Evidence from the 1986 IRCA

We study the impact of immigrant legalization on fiscal transfers from state to local governments in the United States, exploiting variation in legal status from the 1986 Immigration Reform and Control Act (IRCA). State governments allocate more resources to IRCA counties, an allocation that is responsive to the electoral incentives of the governor. Importantly, the effect emerges prior to the enfranchisement of the IRCA migrants and we argue it is driven by the IRCA’s capacity to politically empower already legal Hispanic migrants in mixed legal status communities. The IRCA increases turnout in large Hispanic communities as well as Hispanic political engagement, without detectably triggering anti-migrant sentiment.

Evaluating the revenue and taxation implications of cannabis legalization in South Africa: Insights from Canada and the United States

Purpose: This study aims to evaluate the impact of cannabis legalization on revenue mobilization and taxation in South Africa by analyzing the experiences of jurisdictions that have legalized cannabis. Methodology: A qualitative approach was employed, including a literature review and trend analysis. Data from Canada, California, Colorado, and Washington State, where cannabis has been legalized, were analyzed for 2018-2021. Results: The findings demonstrate that cannabis legalization significantly impacts revenue collection and taxation. However, optimal pricing and taxation policies are crucial to capture the illicit market, minimize negative externalities, and ensure industry growth. Legacy growers and previously disadvantaged individuals should be integrated into the legal market. Theoretical Contribution: The study contributes to the theoretical framework of Pigouvian taxation by examining its applicability to the cannabis industry and the challenges posed by illicit markets and product substitutability with alcohol and tobacco. Practical Implications: The study provides recommendations for South African policymakers on taxation policies, market regulation, and inclusive strategies to ensure a successful and sustainable cannabis industry while maximizing revenue mobilization.

Impact of Legalization on Cannabis Use, Attitudes, and Purchasing Preferences: A Repeated Cross-Sectional Survey of Canadian Young Adults.

The Government of Canada legalized recreational cannabis use in October of 2018 with the implementation of the Cannabis Act. The act aimed to reduce the illicit cannabis market, improve consumer health outcomes, and reduce youth access to cannabis. However, little is known about the attitudes and behaviors of young adults, who have been shown to have a high prevalence of cannabis use, towards cannabis after legalization. In this descriptive study, we examined cannabis use, attitudes, and purchasing preferences among Canadian university-attending young adults both before and after the legalization of cannabis. Participants were recruited from a large Canadian university from 2017 to 2021. Our findings showed that there was an increase in cannabis use immediately following legalization that subsequently decreased in later years. Additionally, attitudes about the legalization of cannabis became more favorable in later years (following legalization), particularly among those who did not use cannabis. Most young adults were also keen to purchase cannabis from a government-owned store before legalization. However, with the exception of past-month consumers, this preference decreased substantially following legalization. The current research adds to the knowledge base about changes in cannabis-related attitudes and use after legalization and focuses on a key population - young adults.

Marriage Equality and the Transnational Flow of Skilled Labor: The Impact of Same-Sex Marriage Legalization in the United States on the Inflow of Skilled Labor

This paper examines the impact on skilled labor migration to the United States of same-sex marriage legalization in European countries and US federal recognition of foreign same-sex marriages. Analyzing US Department of Homeland Security data, we find that European legalization decreased skilled labor admissions to the United States by 22 percent, most notably after six years. However, US recognition of foreign same-sex marriages mitigated this effect post-2013, indicating that such legalizations facilitate skilled labor movement between nations.

Examining the impact of legalization on the prevalence of driving after using cannabis: A comparison of rural and non-rural parts of Canada

Objective The purpose of this study was to examine the likelihood of driving after using cannabis, and of being a passenger with someone who is driving after using cannabis, in rural areas and non-rural areas before and after legalization. Methods A multi-wave analysis of Canada’s National Cannabis Survey was conducted using logistic regression with interactions to predict the prevalence of driving after using cannabis, and of being a passenger with someone who is driving after using cannabis, in relation to place of residence (rural or non-rural) and in the weeks and months before and after legalization. Three time points were compared: pre-legalization, two months following legalization and 1 year after legalization. Results At the national level, there are no significant differences between the predicted estimates of driving after using cannabis for those who live in rural and non-rural areas. However, when examining the impact of legalization, we found a significant increase in driving after using cannabis among rural residents directly following legalization. Furthermore, it was observed that this increase in driving after using cannabis returns to pre-legalization rates one year after legalization. By contrast, in the weeks and months following legalization, driving after using cannabis decreased among those living in non-rural areas, and slowly increased soon thereafter. No significant differences were observed, in either time period or group, in the prevalence of being a passenger with someone who is driving after using cannabis. Conclusions The finding of significantly higher risk of driving after use of cannabis soon after legalization in rural areas suggests a need for more attention to address immediate concerns for public safety. The increased potential for traffic injuries and deaths in other jurisdictions contemplating legalization supports the call for more and better targeted prevention efforts in rural communities that have far too often been overlooked and under-served.

Association between non-medical cannabis legalization and alcohol sales: Quasi-experimental evidence from Canada

BackgroundThere is increasing interest in understanding the impact of non-medical cannabis legalization on use of other substances, especially alcohol. Evidence on whether cannabis is a substitute or complement for alcohol is both mixed and limited. This study provides the first quasi-experimental evidence on the impact of Canada’s legalization of non-medical cannabis on beer and spirits sales. MethodsWe used the interrupted time series design and monthly data on beer sales between January 2012 and February 2020 and spirits sales between January 2016 and February 2020 across Canada to investigate changes in beer and spirits sales following Canada’s cannabis legalization in October 2018. We examined changes in total sales, nationally and in individual provinces, as well as changes in sales of bottled, canned and kegged beer. ResultsCanada-wide beer sales fell by 96 hectoliters per 100,000 population (p=0.011) immediately after non-medical cannabis legalization and by 4 hectoliters per 100,000 population (p>0.05) each month thereafter for an average monthly reduction of 136 hectoliters per 100,000 population (p<0.001) post-legalization. However, the legalization was associated with no change in spirits sales. Beer sales reduced in all provinces except the Atlantic provinces. By beer type, the legalization was associated with declines in sales of canned and kegged beer but there was no reduction in sales of bottled beer. ConclusionsNon-medical cannabis legalization was associated with a decline in beer sales in Canada, suggesting substitution of non-medical cannabis for beer. However, there was no change in spirits sales following the legalization.

The impact of recreational cannabinoid legalization on utilization in a pregnant population.

Marijuana potency and utilization both continue to increase across the United States. While the overall prevalence of cannabinoid utilization during pregnancy has been surveyed in various studies, the direct impact of changing governmental policies on pregnancy use is less characterized. Thus, we aimed to investigate how the legalization of recreational cannabinoid products impacted use during pregnancy in the state of New Mexico. Participants who had a live birth during two study epochs were included: pre-legalization (Epoch 1: 1 January 2019-31 March 2021) and post-legalization (Epoch 2: 1 November 2021-30 November 2022). Participants were further divided into case group [prenatal cannabinoid exposure (PCE)] vs. control (no PCE), with cases being identified by documented self-report or a positive laboratory toxicology test for cannabinoid use during pregnancy. A total of 1,191 maternal/infant dyads were included in Epoch 1, and 378 maternal/infant dyads were included in Epoch 2. In Epoch 1, 788 dyads were controls with 403 cases, while Epoch 2 had 292 controls and 86 cases. Interestingly there was a significant decrease in self-report or positive laboratory toxicology tests in Epoch 2 compared to Epoch 1. Infants born following PCE in both Epoch groups were more commonly born via Cesarean section, had significantly smaller birth weight, length, and head circumference as well as significantly lower Apgar scores at 1 and 5 min. The finding of decreased reported cannabinoid use in the post-legalization group is contradictory to previous studies which have shown increased rates of cannabinoid use after legalization. This could be due to multiple factors including changes in screening practices, the COVID-19 pandemic, and lack of commercialization of THC products. Additional studies are needed to further characterize how changing governmental policies impacts utilization during pregnancy.

Ethical Aspects of Psychedelic-Assisted Treatments: An Overview.

In this chapter, we provide an overview of ethical aspects of psychedelic-assisted treatments in the areas of clinical ethics, research ethics, and at the intersection of psychedelic medicine and society. In contrast to earlier psychedelic research, nowadays medical ethics have been firmly established as a discipline regulating patient-physician relationships which highlight the importance of autonomy, shared decision-making and informed consent in clinical ethics. During and after altered states of consciousness, autonomy is particularly important as participants are in a vulnerable state. In this vulnerable state, both touch and suggestibility are central ethical concerns. In turn, the debate surrounding hallucinogenic and nonhallucinogenic psychedelic substances discusses the importance of altered states of consciousness in general. Of further concern are exceptional training requirements and competencies of psychedelic therapists, as well as the particular context of end-of-life care. Lastly, this section discusses how ethical integrity in clinical treatments can be supported through institutions. In research ethics, inclusivity, research equipoise, and expectation management are key issues in the participation and trials, while open question for the posttrial access to care after psychedelic trials remain. Finally, the chapter addresses the question of equitable access to psychedelic medicine. Furthermore, justice for indigenous communities using psychedelics and the impact of legalization and medicalization of psychedelic substances are pressing ethical concerns amidst the "psychedelic renaissance."

Impact of non-medical cannabis legalization with market restrictions on health service use and incident cases of psychotic disorder in Ontario, Canada

BackgroundCannabis is a risk factor in the onset and persistence of psychotic disorders. There is concern that non-medical cannabis legalization in Canada may have population-level impacts on psychotic disorders. We sought to examine changes in health service use and incident cases of psychotic disorder following cannabis legalization, during a period of tight restrictions on retail stores and product types. MethodsWe conducted a cross-sectional interrupted time-series analysis using linked population-based health administrative data from Ontario (Canada) from January 2014 to March 2020. We identified psychosis-related outpatient visits, emergency department visits, hospitalizations, and inpatient length of stay, as well as incident cases of psychotic disorders, among people aged 14 to 60 years. ResultsWe did not find evidence of increases in health service use or incident cases of psychotic disorders over the short-term (17 month) period following cannabis legalization. However, we found clear increasing trends in health service use and incident cases of substance-induced psychotic disorders over the entire observation window (2014–2020). ConclusionOur findings suggest that the initial period of tight market restriction following legalization of non-medical cannabis was not associated with an increase in health service use or frequency of psychotic disorders. A longer post-legalization observation period, which includes expansion of the commercial cannabis market, is needed to fully understand the population-level impacts of non-medical cannabis legalization; thus, it would be premature to conclude that the legalization of non-medical cannabis did not lead to increases in health service use and incident cases of psychotic disorder.

How does legalisation of same-sex marriage affect stigma against lesbians across different age cohorts in Taiwan

Structural stigma assumes a central role in shaping both individual and interpersonal processes of stigma, while also contributing to health disparities . The recognition of the right to marry serves as a critical benchmark for evaluating a society's commitment to eliminating this structural stigma that affects marginalized groups. The legal sanctioning of same-sex marriage can serve as a protective macro-environmental factor with substantial implications for the psychological well-being and health of same-sex couples. Previous research has predominantly explored how LGBTQ+ individuals make sense of the legalization of same-sex marriage, but it has generally neglected to examine variations across different age cohorts. Also, discussions regarding the impact of same-sex marriage legalization in non-Western contexts remain conspicuously underdeveloped. The present study seeks to bridge these gaps by centering its investigation on Taiwan as the research site and exploring the influence of same-sex marriage legalization on the stigma experienced by lesbians of marriageable age.

Pre-Post Cannabis Legalization for Adult Use: A Trend Study of Two Cohorts of Young Adult Cannabis Users in Los Angeles

ABSTRACT Cannabis was legalized for adult use in California in 2016 for individuals 21 and older. Among 18–20-years-olds, who can possess cannabis legally as medical cannabis patients (MCP) but not as non-patient cannabis users (NPU), the impact of adult use legalization (AUL) on cannabis and other substance use is unknown. Two cohorts of 18–20-year-old cannabis users (MCP and NPU) were surveyed, one in 2014–15 (n = 172 “pre-AUL”) and another in 2019–20 (n = 139 “post-AUL”), using similar data collection methods in Los Angeles, California. Logistic and negative binomial regressions estimated cohort and MCP differences for cannabis and other drug use outcomes based on past 90-day use. In both pre- and post-AUL cohorts, MCP were more likely to self-report medical cannabis use (p < .001) while the post-AUL cohort reported greater use of edibles (p < .01), but fewer mean days of alcohol (p < .05) and cigarette (p < .01) use in multivariate models. Notably, frequency of cannabis use (days or hits per day) did not significantly differ between the pre- and post-AUL cohorts, except for greater use of edibles, despite potentially greater access to cannabis.

Prevalence and correlates of positive parental attitudes towards cannabis use and use intention in Australia during 2016 and 2019

IntroductionWith recent policy changes around medicinal cannabis in Australia, there is concern about the influence of changing norms of cannabis use on adults who are actively parenting. MethodsThis repeated cross-sectional population study used National and Drug Strategy and Household Surveys to estimate the changes and correlates of cannabis-related attitudes (support of legalisation, approve of regular use, would try or use if legal) among Australian parents from 2016 to 2019. ResultsThe estimated proportion of parents who supported legalisation and approved regular cannabis use increased significantly. Parents who would try cannabis if it was legal grew from 5.9% (95 %CI: 5.2, 6.7) to 8.1% (95 %CI: 7.2, 9.0). Parents who said they would use cannabis more often increased from 1.6 (95 % CI: 1.2, 1.9) to 2.9 (95 %CI: 2.4, 3.4), an 81% jump in the three years.The strongest associations were observed between a very high level of psychological distress and regular smoking and drinking. For example, people with a very high level of psychological distress were 2.16 times (95 %CI: 1.42, 3.28) and 2.48 times (95 %CI: 1.61, 3.83) more likely to approve legalisation and regular cannabis use, respectively. Daily drinking was associated with higher odds of trying cannabis (OR = 1.66; CI: 1.25–2.20). Discussion and conclusionThe proportion of parents who would try or use cannabis more often represents a sizeable pool of potential new and frequent users. This highlights the need for education and intervention strategies for parents who use cannabis and care for young children. The associations between mental health and substance use suggest that more research is needed to understand the impact of legalisation on vulnerable groups.

Impact of Recreational Cannabis Legalization on Adolescent Cannabis Use in Washington State

An important public concern about the impact of recreational cannabis legalization is how it may affect adolescent cannabis use. Prior research on this issue has primarily focused on the implications of medical cannabis legalization for adolescents and used data that cover a relatively short post-legalization period. This study extends this line of research by examining the relationship between recreational cannabis legalization and adolescent cannabis use in Washington State, using the National Survey of Drug Use and Health (NSDHU) data from 2005 to 2019. Based on a quasi-experimental research design, this study found some evidence suggesting a positive effect of recreational legalization on the prevalence of adolescent cannabis use and cannabis initiation. Findings suggest the need to create a cannabis regulatory environment that minimizes adolescent access to this drug.

Changes in Cannabis-Attributable Hospitalizations Following Nonmedical Cannabis Legalization in Canada

The impact of adult-use cannabis legalization and subsequent commercialization (ie, increasing store and product access) on hospitalizations in Canada is unclear. To examine changes in overall and subtypes of hospitalizations due to cannabis and associated factors following legalization in Canada and to compare changes between provinces. This repeated cross-sectional analysis included all acute hospitalizations for individuals aged 15 to 105 years in Canada's 4 most populous provinces (Ontario, Quebec, Alberta and British Columbia, population 26.9 million individuals in 2018). Data were obtained from routinely collected health administrative databases. Immediate and gradual changes in the age- and sex-standardized rates of hospitalizations due to cannabis were compared using an interrupted time series design over 3 time periods: prelegalization (January 2015 to September 2018), legalization with product and store restrictions (October 2018 to February 2020), and commercialization, which overlapped with the COVID-19 pandemic (March 2020 to March 2021). Rates of hospitalizations due to cannabis per 100 000 individuals and per 1000 all-cause hospital admissions. There were 105 203 hospitalizations due to cannabis over the 7-year study period, 69 192 of which (65.8%) were among male individuals, and 34 678 (33%) of which were among individuals aged 15 to 24 years. Overall, the age- and sex-standardized rate of hospitalizations increased 1.62 times between January 2015 (3.99 per 100 000 individuals) and March 2021 (6.46 per 100 000 individuals). The largest relative increase in hospitalizations was for cannabis-induced psychosis (rate ratio, 1.40; 95% CI, 1.34 to 1.47 during the commercialization period relative to the prelegalization period). Nationally, legalization with restrictions was associated with a gradual monthly decrease of -0.06 (95% CI -0.08 to -0.03) in hospitalizations due to cannabis per 100 000 individuals. Commercialization and the COVID-19 pandemic were associated with an immediate increase of 0.83 (95% CI, 0.30 to 1.30) hospitalizations due to cannabis per 100 000 individuals. There was provincial variation in changes, with provinces with less mature legal markets experiencing the greatest declines immediately following legalization. This cross-sectional study found that legalization with restrictions was not associated with an increase in hospitalizations due to cannabis but commercialization was. The findings suggest that commercialization of cannabis may be associated with increases in cannabis-related health harms, including cannabis-induced psychosis.

Cannabis-Involved Traffic Injury Emergency Department Visits After Cannabis Legalization and Commercialization

The impact of nonmedical cannabis legalization on traffic injuries and cannabis involvement in traffic injuries is unclear. To examine changes in the number and characteristics of cannabis-involved traffic injury emergency department (ED) visits from before to after legalization and subsequent commercialization (ie, increased retail store and product availability) of cannabis in Ontario, Canada. This repeated cross-sectional study examined changes in cannabis- and alcohol-involved traffic injury ED visits in Ontario, Canada, during 3 time periods: prelegalization (January 2010-September 2018), legalization with product and retail store restrictions (October 2018-February 2020), and commercialization with new products and expanded number of stores, which coincided with the COVID-19 pandemic (March 2020-December 2021). All individuals aged 16 years and older eligible for Ontario's Universal Health Coverage were included. Season- and time-adjusted quasi-Poisson models were used to generate rate ratios with 95% CIs. Data were analyzed from March to April 2023. Quarterly counts of cannabis-involved ED visits for traffic injury. There were 947 604 traffic injury ED visits, of which 426 (0.04%) had documented cannabis involvement and 7564 (0.8%) had documented alcohol involvement. Of the 418 individuals with documented cannabis involvement, 330 (78.9%) were male, 109 (25.6%) were aged 16 to 21 years (mean [SD] age at visit, 30.6 [12.0] years), and 113 (27.0%) had an ED visit or hospitalization for substance use in the 2 years before their traffic injury ED visit. Annual rates of cannabis-involved traffic injury ED visits increased 475.3% over the study period (0.18 visits per 1000 total motor vehicle collisions in 2010 to 1.01 in 2021). Over the same period, alcohol-involved traffic injury ED visits increased by 9.4% (8.03 in 2010 to 8.79 per 1000 traffic injury ED visits in 2021). Legalization with restrictions was associated with a 94% increase in the quarterly rate of cannabis involvement in traffic injury ED visits relative to prelegalization (adjusted rate ratio [aRR], 1.94; 95% CI, 1.37-2.75). Commercialization/COVID-19 was associated with a greater increase of 223% in rates (aRR, 3.23; 95% CI, 2.42-4.33). After adjusting for time trends before legalization, only commercialization/COVID-19 was associated with increased rates. Male sex (adjusted odds ratio [aOR], 3.38; 95% CI, 2.66-4.29), living in the lowest-income neighborhood (aOR, 1.92; 95% CI, 1.39-2.67), being aged 19 to 21 years (aOR, 4.67; 95% CI, 3.27-6.67), and having a prior cannabis-related ED visit (aOR, 8.03; 95% CI, 5.85-11.02) were all positively associated with cannabis involvement during a traffic injury ED visit. This cross-sectional study found large increases in cannabis involvement in ED visits for traffic injury over time, which may have accelerated following nonmedical cannabis commercialization. Although the frequency of visits was rare, they may reflect broader changes in cannabis-impaired driving. Greater prevention efforts, including targeted education and policy measures, in regions with legal cannabis are indicated.

Commentary on Hall et al.: Evaluating impact of cannabis legalization in Canada-initial outcomes and current trends.

Commentary on Hall et al.: Evaluating impact of cannabis legalization in Canada-initial outcomes and current trends.