Cannabis legalization: adhering to public health best practice

Approaches and reporting of alcohol and other drug testing for injured patients in hospital-based studies: A systematic review

ISSUE

Hospital alcohol and/or other drug (AOD) testing is important for identifying AOD-related injuries; however, testing methods vary. This systematic review aimed to examine biological AOD testing methods from hospital-based studies of injured patients and quantify what proportion reported key information on those testing methods.

APPROACH

Observational studies published in English from 2010 onwards involving biological AOD testing for injured patients presenting to hospital were included. Studies examining single injury causes were excluded. Extracted data included concentration thresholds for AOD detection (e.g., lower limits of detection, author-defined cut-offs), test type (e.g., immunoassay, breathalyser) and approach (e.g., routine, clinical discretion), timing of testing, sample type and the proportion of injured cases tested for AODs.

KEY FINDINGS

Of 83 included studies, 76 measured alcohol and 37 other drugs. Forty-nine studies defined blood alcohol concentration thresholds (ranging from 0 to 0.1 g/100 mL). Seven studies defined concentration thresholds for other drugs. Testing approach was reported in 39/76 alcohol and 18/37 other drug studies. Sample type was commonly reported (alcohol: n = 69/76; other drugs: n = 28/37); alcohol was typically measured using blood (n = 60) and other drugs using urine (n = 20). Studies that reported the proportion of cases tested (alcohol: n = 53/76; other drugs: n = 28/37), reported that between 0% and 89% of cases were not tested for alcohol and 0% and 91% for other drugs. Timing of testing was often unreported (alcohol: n = 61; other drugs: n = 30).

IMPLICATIONS AND CONCLUSION

Variation in AOD testing methods alongside incomplete reporting of those methods limits data comparability and interpretation. Standardised reporting of testing methods will assist AOD-related injury surveillance and prevention.

The association between physical availability of cannabis retail outlets and frequent cannabis use and related health harms: a systematic review

An increasing number of regions have or are considering legalising the sale of cannabis for adult use. Experience from tobacco and alcohol regulation has found that greater access to physical retail stores is positively associated with increased substance use and harm. Whether this association exists for cannabis is unclear. We completed a systematic review examining the association between cannabis retail store access and adverse health outcomes. We identified articles up until July 20, 2023 by searching four databases. We included studies examining the association between measures of cannabis store access and adverse outcomes: frequent or problematic cannabis use, healthcare encounters due to cannabis use (e.g., cannabis-induced psychosis), and healthcare encounters potentially related to cannabis (e.g., self-harm episodes). Results were compared by study design type, retail access measure, and by subgroups including: children, adolescents, young adults, adults, and pregnant individuals. This review was registered with PROSPERO (CRD42021281788). The search generated 5750 citations of which we included 32 studies containing 44 unique primary analyses (unique retail measure and outcome pairs). Studies come from 4 countries (United States, Canada, Netherlands and Uruguay). Among the included analyses, there were consistent positive associations between greater cannabis retail access and 1) increased healthcare service use or poison control calls directly due to cannabis (10/12 analyses; 83%) (2) increased cannabis use and cannabis-related hospitalization during pregnancy (4/4; 100%) and 3) frequent cannabis use in adults and young adults (7/11; 64%). There was no consistent positive association between greater cannabis retail and increased frequent cannabis use in adolescents (1/4; 25%), healthcare service use potentially related to cannabis (2/6; 33%) or increased adverse neonatal birth outcomes (2/7; 26.8%). There is a positive association between greater cannabis store access and increases in cannabis harm. In countries with legal cannabis, retail restrictions may reduce use and harm.

Funding

Canadian Centre on Substance Use and Addiction (CCSA).

Access to legal cannabis market in Canada over the four years following non-medical cannabis legalisation

INTRODUCTION

An increasing number of countries are inthe process of legalising non-medical cannabis. We described how the legal market has changed over the first 4 years following legalisation in Canada.

METHODS

We collected longitudinal data on operating status and location of all legal cannabis stores in Canada for the first 4 years following legalisation. We examined per capita stores and sales, store closures, and the drive time between stores and each neighbourhood in Canada. We compared measures between public and private retail systems.

RESULTS

Four years after legalisation, there were 3305 cannabis stores open in Canada (10.6 stores per 100,000 individuals aged 15+ years). Canadians spent $11.85CAD a month on cannabis per individual aged 15+ years, and 59% of neighbourhoods were within a 5-minute drive of a cannabis store. Over 4 years, per capita stores and per capita sales increased each year by an average of 122.3% and 91.7%, respectively, with larger increases in private versus public systems (4.01 times greater for per capita stores and 2.46 times greater for per capita sales). The annual increase in per capita stores and sales during the first 3 years was 6.0 and 15.5 times greater, respectively, than the increase in the fourth year following legalisation. Over 4 years, 7% of retail store locations permanently closed.

DISCUSSION AND CONCLUSION

The legal cannabis market in Canada expanded enormously over the first 4 years following legalisation, with considerable variation in access between jurisdictions. The rapid retail expansion has implications for evaluation of health impacts of non-medical legalisation.

Mental health and cannabis use among Canadian youth: Integrated findings from cross-sectional and longitudinal analyses

BACKGROUND AND PURPOSE

Using data from two methodologically independent youth research studies in Canada, the Health Behaviour in School-aged Children (HBSC) study and the Cannabis, Obesity, Mental health, Physical activity, Alcohol, Smoking, and Sedentary behaviour (COMPASS) study, the objective of this study was to compare associations between youth's mental health and cannabis use across samples. Using similar indicators in both studies, our goal was to affirm the potential for nationally representative cross-sectional analyses (HBSC) to replicate findings found in a longitudinal non-representative data source (COMPASS), enhancing opportunity for causal inferences.

METHODS

Data were collected from grade 9 and 10 Canadian students participating in the 2017/18 HBSC (n=8462) and 2017/18 to 2018/19 waves of COMPASS (n=32,023). Using multivariable Poisson regression models, the strength and statistical significance of the effects of mental health indicators on cannabis use outcomes were estimated within both studies and compared for consistency. Using a 2-year linked sample of students participating in COMPASS, models examining the impact of mental health indicators on cannabis use initiation and maintenance over time were similarly fit using Poisson regression to estimate relative risk.

RESULTS

Similar associations between mental health problems and cannabis use were observed in both data sources. The direction, magnitude, and precision of the estimates for restless sleep, loneliness, poor wellbeing, and cannabis use were highly comparable across both studies. Worse mental health was consistently associated with current and lifetime cannabis use among youth.

DISCUSSION

Cross-sectional and longitudinal findings from two large methodologically diverse studies in Canada demonstrate a replicable association between indicators of mental health and youth cannabis use. Similarities were identified and two generalizations may be concluded: 1) potentially causal etiological relationships inferred from HBSC data were supported in longitudinal findings based on COMPASS, and 2) longitudinal COMPASS data aligns with nationally representative data from HBSC.

Changes in health harms due to cannabis following legalisation of non-medical cannabis in Canada in context of cannabis commercialisation: A scoping review

ISSUE

On 17 October 2018, Canada legalised non-medical cannabis. Critically, the cannabis market in Canada has changed considerably since legalisation. In this scoping review, we identified available evidence on changes in cannabis-related health harms following legalisation and contextualised findings based on legal market indicators.

APPROACH

Electronic searches were conducted to identify studies that compared changes in cannabis-related health harms pre- and post-legalisation. We contextualised each study by the mean per capita legal cannabis stores and sales during the study period and compared study means to per capita stores and sales on October 2021-3 years following legalisation.

IMPLICATIONS AND CONCLUSIONS

Some measures of cannabis harms have increased since legalisation but studies to date have captured periods of relatively low market maturity. Longer-term monitoring of health harms as the market continues to expand is indicated.

Cannabis and metformin on diabetic male Wistar rat sperm and reproductive organ parameters

Purpose

Cannabis use has reportedly increased in type 2 diabetic users as a possible co-treatment for associated pain and inflammation. Both cannabis and metformin (an anti-diabetic drug) have a limited number of studies completed on their effect on male reproductive parameters in a diabetic model. This study determined if cannabis and metformin administration alter various reproductive parameters in diabetic male rats.

Methods

Male Wistar rats (n = 35) were fed on a high fat diet and injected with streptozotocin (30 mg/kg rat) to induce a type-2 diabetic model. Treatment groups received cannabis based on Delta-9-Tetrahydrocannabinol (THC) concentrations of 1.25, 2.5 and 5 mg/kg per rat and metformin (50 mg/kg) every alternate day for 10 weeks. Organ weight; serum testosterone levels and sperm count, motility, lipid peroxidation, citrate synthase and lactate dehydrogenase activities were measured.

Results

Cannabis treatment induced a significant concentration dependent decrease in sperm motility at 5 mg/kg rat THC (P = 0.009) administration. Metformin significantly (P = 0.035) increased sperm counts and lactate dehydrogenase activity (P = 0.002). Both cannabis and metformin negatively affected testosterone concentrations.

Conclusions

Cannabis needs to be used cautiously as an alternative treatment in diabetic males based on the negative effects observed for the various reproductive parameters in this diabetic rat model.

The association between recreational cannabis legalization, commercialization and cannabis-attributable emergency department visits in Ontario, Canada: an interrupted time-series analysis

BACKGROUND AND AIMS

Recreational cannabis was legalized in Canada in October 2018. Initially, the Government of Ontario (Canada's largest province) placed strict limits on the number of cannabis retail stores before later removing these limits. This study measured changes in cannabis-attributable emergency department (ED) visits over time, corresponding to different regulatory periods.

DESIGN

Interrupted time-series design using population-level data. Two policy periods were considered; recreational cannabis legalization with strict store restrictions (RCL, 17 months) and legalization with no store restrictions [recreational cannabis commercialization (RCC), 15 months] which coincided with the COVID-19 pandemic. Segmented Poisson regression models were used to examine immediate and gradual effects in each policy period.

SETTING

Ontario, Canada.

PARTICIPANTS

All individuals aged 15-105 years (n = 13.8 million) between January 2016 and May 2021.

MEASUREMENTS

Monthly counts of cannabis-attributable ED visits per capita and per all-cause ED visits in individuals aged 15+ (adults) and 15-24 (young adults) years.

FINDINGS

We observed a significant trend of increasing cannabis-attributable ED visits pre-legalization. RCL was associated with a significant immediate increase of 12% [incident rate ratio (IRR) = 1.12, 95% confidence interval (CI) = 1.02-1.23] in rates of cannabis-attributable ED visits followed by significant attenuation of the pre-legalization slope (monthly slope change IRR = 0.98, 95% CI = 0.97-0.99). RCC and COVID-19 were associated with immediate significant increases of 22% (IRR = 1.22, 95% CI = 1.09-1.37) and 17% (IRR = 1.17, 95% CI = 1.00-1.37) in rates of cannabis-attributable visits and the proportion of all-cause ED visits attributable to cannabis, respectively, with insignificant increases in monthly slopes. Similar patterns were observed in young adults.

CONCLUSIONS

In Ontario, Canada, cannabis-attributable emergency department visits stopped increasing over time following recreational cannabis legalization with strict retail controls but then increased during a period coinciding with cannabis commercialization and the COVID-19 pandemic.

A Systematic Review and Narrative Synthesis of the Evolution of Adolescent and Young Adult Cannabis Consumption Before and After Legalization

PURPOSE

To systematically review evidence assessing the evolution of cannabis consumption before and after the implementation of non-medical cannabis legislation.

METHODS

MEDLINE, PubMED, PsycINFO, Scopus, and Web of Science were systematically searched for studies that examined change in cannabis consumption before and after nonmedical cannabis legislation. Data were tabulated by study design, levels of consumption, and individual subgroups. Data were analyzed using a narrative synthesis approach, considering study quality.

RESULTS

32 studies were included (11 higher quality and 21 lower quality). 40% of higher quality evidence supported an increase in postlegalization consumption (55% did not report a change and 5% reported a decrease). The increase was most evident for young adults (42% of higher quality evidence) and in the consumption in the past month (37% of higher quality evidence). There was limited supporting evidence for new users having grown in response to legalization. Based on subgroup analysis, the increase in postlegalization consumption was higher among women and those who engage in binge-drinking.

CONCLUSIONS

Higher quality evidence suggests an increase in adolescent past-month consumption of cannabis following legalization in several geographical jurisdictions. Consumption evolution prelegalization and postlegalization differed by age group and for young women and for binge drinkers. Consumption evolution differences suggest a variety of strategies might be required in efforts to lower public health impacts of cannabis consumption following legalization.

Non-medical cannabis use: international policies and outcomes overview. An outline for Portugal

INTRODUCTION

Cannabis is probably the most commonly used illicit drug. It is often regarded as a relatively nonharmful experience, even though evidence indicates otherwise. Legalization of non-medical cannabis, which has already taken place in several countries, is currently a controversial issue.

OBJECTIVE

To provide an up-to-date overview of current models and policies and their outcomes that can inform future political decisions regarding non-medical cannabis use.

METHODS

PubMed/MEDLINE and Google Scholar scientific databases were searched for articles written in English, Spanish, and Portuguese published between 1990 and December 2020. The reference lists of these articles were similarly used as bibliography sources. Gray literature was also included.

RESULTS

While non-medical cannabis has been decriminalized in many countries, it has only been legalized in Uruguay, Canada, and some U.S. states. Several benefits of legalization were identified: decreases in cannabis-related crimes, law-enforcement and judicial costs; reduction in synthetic cannabis supply; decline in black economies and possible diminution of other illegal drug buying; and tax revenue increases. Reported legalization problems included: increases in cannabis use; cannabis-related disorders; and cannabis-related accidents and hospitalizations. Harm-reduction strategies are available in the scientific literature.

CONCLUSION

Growing, although incomplete, evidence exists to guide policy makers, minimize cannabis-related harm, and positively contribute to public health, if the legalization path is to be followed. Dialogue between legislators and science should be encouraged. There are more than a few legalization pathways, with diverse economic, social and health wellbeing effects. Public health-driven, instead of profit-driven models, seem to offer the most benefits regarding non-medical cannabis legalization. Most of the true public health effects of cannabis legalization are still unknown, for we are still in the early stages of these policies and their implications. Future studies should address the medium-to-long-term social, economic, and health consequences of legalization policies.

Towards quantifying the reciprocal associations between frequency of cannabis use and alcohol consumption: a cross-lagged analysis from the CONSTANCES cohort

OBJECTIVE

Disentangle the temporal relationships between frequency of cannabis use and alcohol consumption.

METHODS

A cross-lagged model providing standardised coefficients (SCs)±their standard errors in 13 255 men and 13 696 women enrolled in 2015 or 2016 in the French population-based 'CONSulTANts des Centres d'Examens de Santé' (CONSTANCES) cohort. Cannabis use was categorised as follows: 'No use during the past 12 months', 'Use during the past 12 months but not in the past month' and 'Use in the past month' for cannabis use at baseline, and No use during the past 12 months, 'Use less than once per month' and 'Use once per month or more' for cannabis use at 1 year of follow-up. Alcohol consumption was measured at baseline and at 1 year of follow-up and three categories were determined: low risk (<28 drinks per week in men; <14 drinks per week in women), moderate risk (≥28 and<42 in men; ≥14 and<28 in women) and high risk (≥42 in men; ≥28 in women). Analyses were adjusted for age, sex, education, income, tobacco consumption, self-rated health status and depressive symptoms.

RESULTS

Both associations from alcohol to cannabis and from cannabis to alcohol were significant (SC=0.02±0.01 with p=0.003 and SC=0.06±0.01 with p<0.001, respectively). However, the SC of the association from cannabis to alcohol was three times higher than the opposite association (p<0.001). After stratification for sex, SCs of the association from cannabis to alcohol were more than two times higher than for the opposite association in men, and more than four times higher in women (both p<0.001).

CONCLUSIONS

The association between frequency of cannabis use and subsequent alcohol consumption was stronger than the opposite association. This finding encourages considering the risk of increased alcohol consumption among cannabis users.

Characteristics that influence purchase choice for cannabis products: a systematic review

Introduction

When non-medical cannabis use became legal, government regulators implemented policies to encourage safer consumption through access to a regulated market. While this market is growing, sales still occur through unregulated channels. This systematic review identifies factors influencing cannabis purchasing to help policymakers understand why consumers still purchase illicit market cannabis (registered with PROSPERO CRD42020176079).

Methods

A comprehensive search strategy included databases in health, business, and social science fields (inception to June 2020). Studies were eligible for inclusion if they were conducted with persons who purchase cannabis and examine at least one attribute that would influence purchase choice and were published in the English language. Studies could be of any methodological design. Two independent reviewers completed two levels of screening, and all extraction was verified by a second reviewer. A qualitative synthesis of the findings was completed. The quality of the included studies was assessed using the Mixed Methods Appraisal Tool.

Results

Of the 4839 citations screened, 96 were eligible for full-text review and 35 were included in the final synthesis. Aspects of price were the most common factors (27 studies). Twenty studies measured price elasticity; most studies found that demand was price inelastic. Many other attributes were identified (e.g., product quality, route of administration, product recommendations, packaging), but none were explored in depth. Eleven studies addressed aspects of product quality including demand elasticity based on quality, potency, and aroma. Studies also explored consumer-perceived “quality” but provided no definition; differences in quality appeared to impact consumer choice. Smoking cannabis appeared to be the preferred route of administration but was only examined in three studies. There was insufficient data to understand in the impact of other attributes on choice. There appeared to be preference heterogeneity for different attributes based on the consumer’s experience, reason for use, and gender.

Conclusion

While price influences choices, demand is relatively inelastic. This suggests that consumers may be seeking lowest-cost, unregulated cannabis to avoid reducing consumption. Beyond price, there is a significant gap in our understanding of consumer choices. Perceived quality does appear to impact choice; however, more research is needed due to the lack of a recognized definition for cannabis quality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42238-022-00117-0.

How has access to legal cannabis changed over time? An analysis of the cannabis retail market in Canada 2 years following the legalisation of recreational cannabis

INTRODUCTION

This study describes the legal recreational cannabis market across Canada over the 2 years following legalisation. We compared changes in access to the legal cannabis retail market for all provinces and territories (jurisdictions) in Canada and explored differences between jurisdictions.

METHODS

We collected data for all legal cannabis stores in Canada over five time periods following legalisation in October 2018. We examined the following measures by jurisdiction and retail model (public vs. private operation): absolute and per capita store numbers, hours of operation and store access across neighbourhoods.

RESULTS

Two years following legalisation, there were a total of 1183 legal cannabis stores open across Canada (3.7 stores per 100 000 individuals aged 15+). There was wide variation between jurisdictions in access to retail stores, with the lowest stores per capita in Quebec and Ontario (0.6 and 1.6 per 100 000), and the highest in Alberta and Yukon (14.3 per 100 000 in both). Jurisdictions with private retail models had more stores (4.8 vs. 1.0 per 100 000), held greater median weekly hours (80 vs. 69) and experienced greater store growth over time compared to public models. After adjusting for confounders, there were 1.96 times (95% confidence intervals: 1.84, 2.09) more cannabis stores within 1000 m of the lowest- compared to the highest-income quintile neighbourhoods.

DISCUSSION AND CONCLUSIONS

While access to the recreational cannabis retail market has increased following legalisation, there is substantial variation in access between jurisdictions and evidence of concentration in lower-income neighbourhoods. These differences may contribute to disparities in cannabis use and harms.

Compliance With Cannabis Act Regulations Regarding Online Promotion Among Canadian Commercial Cannabis-Licensed Firms

IMPORTANCE

As global jurisdictions shift toward cannabis legalization, 2 areas of public health importance relate to exposure to youth and to truthful promotion. Although Canada's Cannabis Act specifies many prohibitions related to cannabis promotion, no systematic monitoring or enforcement among licensed firms exists. Compliance with marketing regulations has effects beyond Canadian citizens because of the global outreach of websites and social media.

OBJECTIVES

To evaluate compliance among licensed firms with the Cannabis Act and analyze trends among violations regarding promotional material.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study evaluated cannabis-licensed firms after cannabis legalization. Data were extracted from online public platforms, including company websites, Facebook, Instagram, and Twitter, from October 1, 2019, to March 31, 2020. Descriptive statistics, Poisson regression, and logistic regression were used to analyze the associations of covariates with promotion violations.

MAIN OUTCOMES AND MEASURES

The primary outcome was characterization of type and prevalence of promotion violations. Secondary outcomes were the role of various covariates (namely, licensed firm characteristics and online platforms) in the frequency and probability of violations. Hypotheses were formulated before data collection.

RESULTS

Among 261 licensed firms, 211 (80.8%) had an online platform, including 204 (96.7%) with websites, 128 (60.7%) with Facebook, 123 (58.3%) with Instagram, and 123 (58.3%) with Twitter. Of all licensed firms with an online platform, 182 (86.3%) had at least 1 violation. Compared with websites, the risk of violations was significantly higher on Facebook (rate ratio [RR], 1.24; 95% CI, 1.11-1.39) and Instagram (RR, 1.19; 95% CI, 1.05-1.34). The most common violations included lack of age restrictions, brand glamorization, and omission of risk information. With websites as the reference group, lack of age restrictions was approximately 15 times more likely to occur on Facebook (odds ratio [OR], 14.76; 95% CI, 8.06-27.05); the odds of an age restriction violation were also higher on Instagram (OR, 2.48; 95% CI, 1.43-4.32) and Twitter (OR, 4.03; 95% CI, 2.29-7.09). For unsubstantiated claims, the odds of violations were significantly decreased on Facebook (OR, 0.23; 95% CI, 0.11-0.48) and Instagram (OR, 0.28; 95% CI, 0.14-0.57). The odds of glamorization were associated with an increase on Instagram (OR, 2.90; 95% CI, 1.72-4.88).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, widespread violations were observed in online Canadian cannabis promotion. To protect public health and safety amid legalization, decision-makers should make explicit federal regulation and enforcement regarding promotional activities of cannabis retailers. These results suggest that policy and enforcement of cannabis promotion in Canada would have an international impact, from ease of access to online media and downstream consequences of unregulated promotion.

Trends in youth cannabis use across cannabis legalization: Data from the COMPASS prospective cohort study

Canada legalized recreational cannabis use for adults on October 17, 2018 with decision-makers emphasising the need to reduce cannabis use among youth. We sought to characterise trends of youth cannabis use before and after cannabis legalization by relying on a quasi-experimental design evaluating cannabis use among high school students in Alberta, British Columbia, Ontario, and Québec who participated in the COMPASS prospective cohort study. Overall trends in use were examined using a large repeat cross-sectional sample (n = 102,685) at two time points before legalization (16/17 and 17/18 school years) and one after (18/19 school year). Further differential changes in use among students affected by legalization were examined using three sequential four-year longitudinal cohorts (n = 5,400) of students as they progressed through high school. Youth cannabis use remains common with ever-use increasing from 30.5% in 2016/17 to 32.4% in 2018/19. In the repeat cross-sectional sample, the odds of ever use in the year following legalization were 1.05 times those of the preceding year (p = 0.0090). In the longitudinal sample, no significant differences in trends of cannabis use over time were found between cohorts for any of the three use frequency metrics. Therefore, it appears that cannabis legalization has not yet been followed by pronounced changes on youth cannabis use. High prevalence of youth cannabis use in this sample remains a concern. These data suggest that the Cannabis Act has not yet led to the reduction in youth cannabis use envisioned in its public health approach.

Growing pains: An overview of cannabis quality control and quality assurance in Canada

In the past decade, the predominant prohibition model for cannabis use has shifted towards a regulated legal model, most widely in the context of medical purposes. In 2018, Canada became the first G7 country to legalize cannabis for adult use, implementing a two-phase roll-out of cannabis regulations. A stated goal of the new legal framework is to minimize harms by providing a safe supply of cannabis to Canadian consumers. One way that this can be achieved is through appropriate Quality Control and Quality Assurance (QC/QA) measures. Canada has implemented stringent QC/QA measures for all classes of cannabis, which include requirements such as labelling THC and CBD content per product and limiting THC doses. This paper will provide an overview of the current QC/QA measures in Canada, highlighting differences based on class of cannabis and consider the strengths and weaknesses of the current standards. QC/QA standards represent a key safety feature that can enable informed purchasing and provide consumers with necessary information about various cannabis products. As Canada continues to progress its cannabis policies, QC/QA measures provide a key consideration for ensuring Canada meets its objective of providing a safe supply of cannabis to Canadian consumers.

Facing the option for the legalisation of cannabis use and supply in New Zealand: An overview of relevant evidence, concepts and considerations

ISSUES

Non-medical cannabis policies are changing, including towards legalisation-with-regulation frameworks. New Zealand will hold a public referendum on cannabis legalisation in 2020. We reviewed data on cannabis use and health/social harms; policy reform options; experiences with and outcomes of reforms elsewhere; and other relevant considerations towards informing policy choices in the upcoming referendum.

APPROACH

Relevant epidemiological, health, social, criminal justice and policy studies and data were identified and comprehensively reviewed.

KEY FINDINGS

Cannabis use is common (including in New Zealand) and associated with risks for health and social harms, mainly concentrated in young users; key harms are attributable to criminalisation. 'Decriminalisation' reforms have produced ambivalent results. Existing cannabis legalisation frameworks vary considerably in main parameters. Legalisation offers some distinct advantages, for example regulated use, products and user education, yet outcomes depend on essential regulation parameters, including commercialisation, and policy ecologies. While major changes in use are not observed, legalisation experiences are inconclusive to date, including mixed health and social outcomes, with select harms increasing and resilient illegal markets. It is unclear whether legalisation reduces cannabis exposure or social harms (e.g. from enforcement) for youth.

IMPLICATIONS/CONCLUSIONS

No conclusive overall evidence on the outcomes of legalisation elsewhere exists, nor is evidence easily transferable to other settings. Legalisation offers direct social justice benefits for adults, yet overall public health impacts are uncertain. Legalisation may not categorically improve health or social outcomes for youth. Legalisation remains a well-intended, while experimental policy option towards more measured and sensible cannabis control and overall greater policy coherence, requiring close monitoring and possible adjustments depending on setting-specific outcomes.

Perceptions of cannabis health information labels among people who use cannabis in the U.S. and Canada

BACKGROUND

The emergence of legal cannabis industries poses a new public health challenge. Health information labels are part of the public health strategy for tobacco and alcohol, but there is limited research on cannabis-related messaging. This study explored perceptions of cannabis health information labels among people who used cannabis in the last 12 months residing in the U.S. and Canada.

METHODS

The Global Drug Survey (GDS) is a large anonymous cross-sectional web-survey. In GDS2019, respondents were presented with six labels with cannabis-related health information (dependence; driving stoned; harms of smoking; harms to developing brain; lack of motivation; effects on memory), and asked if information was new, believed, would it change behavior, and about acceptability of having health labels on legal products. This paper includes 1,275 respondents from Canada and 2,224 from U.S. states where cannabis was legal at the time of the survey, and 5,230 from other U.S. states.

RESULTS

Few respondents said that the information was new (6.6-24.6%). Most said the information was believable (63.5-72.0%) other than for the dependence message (28.1% new, 56.8% believed), which was perceived to be the least likely to change behavior (10.2%). Driving stoned was the message perceived to be the most likely to change behavior (58.5%). Respondents living in Canada were less likely to say information was new and rated most messages more believable than those in the U.S. Respondents from legal U.S. states were less likely to say information was new compared to other states. Respondents who used cannabis daily rated acceptability of labels lower (27.8%) than those using 1-48 days (40.6%).

CONCLUSIONS

Novel, believable information may be more effective at changing behavior. Regular consumers may be less susceptible to messages. Information focusing on safer use strategies and benefits of reducing use may be more acceptable and should be assessed in future research.

Vape Club: Exploring Non-Profit Regulatory Models for the Supply of Vaporised Nicotine Products

Vaporised nicotine products (VNPs) that are not approved as therapeutic goods are banned in some countries, including Australia, Singapore, and Thailand. We reviewed two non-profit regulatory options, private clubs and the Australian Therapeutic Goods Administration Special Access Scheme (SAS) that have been applied to other controlled substances (such as cannabis) as a potential model for regulating VNPs as an alternative to prohibition. The legal status of private cannabis clubs varies between the United States, Canada, Belgium, Spain, and Uruguay. Legal frameworks exist for cannabis clubs in some countries, but most operate in a legal grey area. Kava social clubs existed in the Northern Territory, Australia, until the federal government banned importation of kava. Access to medical cannabis in Australia is allowed as an unapproved therapeutic good via the SAS. In Australia, the SAS Category C appears to be the most feasible option to widen access to VNPs, but it may have limited acceptability to vapers and smokers. The private club model would require new legislation but could be potentially more acceptable if clubs were permitted to operate outside a medical framework. Consumer and regulator support for these models is currently unknown. Without similar restrictions applied to smoked tobacco products, these models may have only a limited impact on smoking prevalence. Further research could explore whether these models could be options for regulating smoked tobacco products.

The efficacy of computerized interventions to reduce cannabis use: A systematic review and meta-analysis

BACKGROUND AND AIMS

Cannabis is the most widely consumed illicit drug. Although it is too early to confirm the impact of legalization, the use of cannabis appears to be on the rise in some countries due to its authorization for medical/recreational purposes. Among different types of therapeutic approaches to reduce cannabis use, computerized interventions are becoming a new treatment option. To assess their efficacy, a systematic review and meta-analysis was conducted.

METHODS

A systematic review and meta-analysis was performed employing randomized controlled clinical trials indexed in MEDLINE and PsycINFO. The principal outcome measure was cannabis use, and the secondary one was the use of other substances during interventions. A subgroup analysis was conducted by length of follow-up, number of sessions, age group, type of analysis, and type of control condition.

RESULTS

The meta-analysis included nine studies with 2963 participants. Computerized interventions resulted in significant reductions in the use of cannabis (standardized mean difference [SMD]: -0.19; 95% CI: -0.26, -0.11) and other substances (SMD: -0.27; 95% CI: -0.46, -0.08).

CONCLUSIONS

Computerized interventions examined in the present study reduced the frequency of cannabis and other substance use. Limitations included the recalculation of dichotomous and continuous data as SMD and the lower number of studies included in the secondary outcome. Computerized interventions could be a viable option to reduce cannabis use.

Influence of legal status on the uptake of cannabis in young people

PURPOSE OF REVIEW

Policies that limit young people's access to cannabis may reduce early onset of use and minimize health-related harm. This review article provides an update of recent research examining the influence of the cannabis policy frameworks on the use of cannabis by young people.

RECENT FINDINGS

There are significant concerns that ongoing policy changes in favour of legalization will increase the uptake of cannabis by young people. Evidence to support a causal effect of cannabis policy changes on increased uptake by young people is lacking; more time may be needed to assess the impact because the policies are still evolving. Policy changes in favour of legalization were associated with reduced risk perception although this may be a cause or consequence. The need to situate the impact of these policies in the context of specific policy features, social norms and perceptions about cannabis has been highlighted.

SUMMARY

A more nuanced understanding of the impact of the legal status of cannabis on young people is needed to build evidence for future policy options. The impact of these policies may not be immediately apparent but limiting young people's access to cannabis must be prioritized during policy deliberations.