The implementation and public health impacts of cannabis legalization in Canada: a systematic review

Understanding youth and young adult cannabis use in Canada post-legalization: a scoping review on a public health issue

BACKGROUND

Canada legalized recreational cannabis in 2018, and one of the primary objectives of the Cannabis Act was to protect youth by reducing their access to cannabis and providing public education. Canada has the highest prevalence of cannabis use worldwide, particularly among youth and young adults under the age of 25. Cannabis use is linked with many adverse effects for youth and young adults including psychosis, anxiety, depression, respiratory distress, cannabinoid hyperemesis syndrome, and impaired cognitive performance. Despite the high prevalence of cannabis use and the evolution of policies in Canada and globally, significant knowledge and research gaps remain regarding youth and young adult cannabis use. The aim of this scoping review is to map the extent, nature, and range of evidence available on youth and young adult cannabis use in Canada since its legalization, in order to strengthen policies, services, treatments, training, and public education strategies.

METHODS

Using a scoping review framework developed by Arksey and O'Malley, along with the PRISMA-ScR guidelines, we conducted a rigorous search in five academic databases: MEDLINE, Embase, APA PsycINFO, CINAHL and Web of Science Core Collection. We included empirical studies that collected data in Canada after the legalization of recreational cannabis (October 2018) and focused on youth or young adults < 30. Two reviewers independently screened articles in two stages and extracted relevant information from articles meeting the inclusion criteria.

RESULTS

Of the 47 articles meeting our inclusion criteria, 92% used quantitative methods, 6% were qualitative, and 2% used a mixed-methods approach. Over two-thirds (68%) used secondary data. These studies were categorized into six focus areas: (1) prevalence, patterns, and trends, (2) cannabis-related injuries and emergency department (ED) visits, (3) rates and patterns during the pandemic, (4) perceptions of cannabis use, (5) prevention tools, and (6) cannabis-related offenses. Key findings from the studies reviewed include an increase in cannabis use among 18-24-year-olds post-legalization, with mixed results for youth under 18. ED visits for intentional and unintentional cannabis-related injuries have increased in young children and teens. Perception studies show a mix of concern and normalization of cannabis use. Though limited, prevention studies are promising in raising awareness. A decline in cannabis-related offenses was noted by one study. The review highlights several research gaps, including the need for more qualitative data, disaggregation of demographic data, intervention research, and comprehensive studies on the physical and mental health impacts of cannabis use among youth and young adults.

CONCLUSION

Maintaining a public health approach is critical, with a focus on reducing the high prevalence of cannabis use among youth and young adults. This involves implementing prevention strategies to minimize harms, enhancing public education, minimizing commercialization, reducing youth access to cannabis, promoting guidelines for lower-risk cannabis use and harm reduction strategies, and increasing training for healthcare providers.

Road safety implications of the partial legalisation of cannabis in Germany: protocol for a quasi-experimental study

INTRODUCTION

Germany is reforming its legal approach to cannabis, allowing the possession and cultivation of cannabis for recreational purposes. The objective of this study is to investigate the impact of the policy reform on (1) The prevalence of cannabis use in the general population and (2) Driving under the influence of cannabis (DUIC) among regular users.

METHODS AND ANALYSIS

A quasi-experimental research design will be employed, with repeated cross-sectional surveys on self-reported DUIC and cannabis use conducted at three measurement points in Germany (intervention group) and Austria (control group) over a 2-year observation period (2023-2025). Data will be collected from approximately 50 000 individuals aged between 18 years and 64 years. To minimise reporting biases in the measurement of DUIC, we will use direct and indirect assessments via crosswise model and motor vehicle accident data from official statistics. In a difference-in-difference framework, regression analyses and interrupted time series analysis will be carried out for hypothesis testing.

ETHICS AND DISSEMINATION

Participants will be informed about voluntary participation, data protection laws and the option to delete data on request. Ethical approval was obtained from the Local Psychological Ethics Committee of the Centre for Psychosocial Medicine in Hamburg, Germany (reference number: 0686). Findings will be disseminated through scientific networks and will be key for a comprehensive evaluation of the cannabis law reform. The findings will facilitate the design and implementation of road safety measures.

Cannabis use motives and associations with personal and work characteristics among Canadian workers: a cross-sectional study

BACKGROUND

Research on cannabis use motives has focused on youth. Little is known about motives among working adults, including how work may play a role. This study aimed to describe cannabis use motives and their connection to work, and identify the personal and work correlates of work-related motives among a sample of workers.

METHODS

A national, cross-sectional sample of Canadian workers were queried about their cannabis use. Workers reporting past-year cannabis use (n = 589) were asked their motives for using cannabis and whether each motive was related to work or helped them manage at work (i.e., work-related). Multinomial logistic regression analyses were conducted to estimate the associations of personal and work characteristics with work-related cannabis use motives (no work-related motives, < 50% of motives work-related, ≥ 50% of motives work-related).

RESULTS

Use for relaxation (59.3%), enjoyment (47.2%), social reasons (35.3%), coping (35.1%), medical reasons (30.9%), and sleep (29.9%) were the most common motives. Almost 40% of respondents reported one or more of their cannabis use motives were work-related, with coping (19.9%) and relaxation (16.3%) most commonly reported as work-related. Younger age, poorer general health, greater job stress, having a supervisory role, and hazardous work were associated with increased odds of reporting at least some cannabis use motives to be work-related, while work schedule and greater frequency of alcohol use were associated with reduced odds of motives being primarily work-related.

CONCLUSIONS

Cannabis use motives among workers are diverse and frequently associated with work. Greater attention to the role of work in motivating cannabis use is warranted.

Cannabis legalization and hospitalizations in Alberta: Interrupted time series analysis by age and sex

OBJECTIVES

Recent research has focused on the effects of legalization on cannabis-related emergency department visits, but the considerable healthcare costs of cannabis-related hospitalizations merit attention. We will examine the association between recreational cannabis legalization and cannabis-related hospitalizations.

METHODS

A cohort of 3,493,864 adults from Alberta was examined (October 2015-May 2021) over three periods: pre-legalization, post-legalization of flowers and herbs (phase one), and post-legalization of edibles, extracts, and topicals (phase two). Interrupted time series analyses were used to detect changes.

RESULTS

The study found an increase in hospitalization rates among younger adults (18-24) before legalization, yet no increased risk was associated with cannabis legalization, for either younger (18-24) or older adults (25+).

CONCLUSIONS

Clinicians should be aware of the increased risk in younger groups and may benefit from early identification and intervention strategies, including screening and brief interventions in primary care settings.

Uneven effects of twenty years of Chile's cannabis policy implementation in cannabis onset

BACKGROUND

In Chile, Laws 19366 and 20000, implemented in 1995 and 2005 respectively, regulated and sanctioned cannabis' personal use, cultivation and trafficking.

METHODS

We use thirteen biannual cross-sectional national surveys data from 1994 to 2018 to examine the effect of Laws 19366 and 20000-using the rate of individuals incarcerated per 100000 population due to drug-related crimes as proxy-on the age of onset of cannabis use over time. We estimate the effect of these policies using a mixed proportional hazards framework that models the transition to first cannabis use in 47,832 individuals aged 12-21.

RESULTS

Overall, changes in these laws did not affect the transition to first cannabis use. However, increases in the rate of individuals incarcerated were associated with decreases on the age of onset of cannabis use in females and individuals living in affluent neighborhoods or in specific regions.

CONCLUSION

We find no evidence of cannabis policy changes affecting the age of onset of cannabis use across all individuals aged 12-21. Policy effects associated with decreases in cannabis onset age in females and individuals from affluent neighborhoods or specific regions can be explained by using theoretical frames that recognize specific dynamics of cannabis supply and demand.

What impact could the legalisation of recreational cannabis have on the health of the UK? Lessons from the rest of the world

Several jurisdictions across the globe have introduced legislation to legally permit the sale and consumption of recreational cannabis. This editorial considers current evidence from the rest of the world and asks how this might inform the possible consequences of 'legalisation' models in the UK.

Commentary: The Conflict Between Protecting Public Health and Raising Tax Revenue

When Canada created a legal market for cannabis, it gave priority to public health by restricting marketing using branding and promotion via social and other media sources. These restrictions to protect the public from harmful use are under increasing pressure from the legal cannabis industry, which claims that they prevent them from outcompeting and replacing the illicit market. Public health advocates are reasonably concerned that these restrictions will not hold given our experience with alcohol, tobacco and gambling where governments' fiscal dependence on tax revenue favours the liberalization of regulation.

Five Years After Cannabis Legalization, Is It Time to Ease Restrictions on Promotion?

In the spring of 2024, the federal government is expected to report on its legislative review of the Cannabis Act (2018). One of the most contentious issues is whether to relax restrictions on cannabis promotion. This commentary describes the tension between the public health aims of legalization and the secondary aim of displacing the illicit market. We maintain that among jurisdictions that have legalized cannabis, Canada stands out as having the stated primary objective of safeguarding public health, and its restrictions on promotion are evidence-based and innovative. These measures must be preserved, even in the face of growing industry pressure to loosen them.