The impact of cannabis legalization in Uruguay on adolescent cannabis use

Current Status of Cannabis Legalization and Decriminalization Efforts in Nepal

The unique historical and cultural background of Nepal has shaped its perspective on cannabis usage. Narcotic Drugs Control Act 1976 of Nepal prohibits the cultivation, production, manufacture, sales, and distribution of narcotic drugs, which also include various forms of cannabis. With proponents for cannabis legalization increasing in the country, it is equally crucial to analyze context and practices in countries already adopting legalization. As such, this article contextualizes the current debates in Nepal with global policies and practices and talks about the possible impacts of changing the laws on society, the economy, and public health. Policymakers in Nepal must make decisions based on evidence and facts when deciding how to regulate cannabis.

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.

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.

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).

Is legalization of recreational cannabis associated with levels of use and cannabis use disorder among youth in the United States? A rapid systematic review

Cannabis legalization policies are rapidly changing in the United States. While there are concerns that recreational legalization will negatively affect young people, previous reviews have not provided clear indication of such effects. The purpose of this rapid systematic review was to examine whether recreational legalization was associated with increases in prevalence of cannabis use and use disorder among adolescents and young adults. PubMed/MEDLINE, Embase, Scopus, PsycInfo, Web of Science, Dissertations & Theses Global, the Trip Database, and OpenGrey were searched from date of inception through Marcy 17, 2022 to retrieve all relevant records. English language and human subject filters were applied. Two reviewers screened abstracts and titles, assessed full text articles, and coded the final included articles. Studies including primarily 10- to 19-year-olds were classified as adolescent, and those between 18 and 26 years as young adult. Our search identified 33 research reports (22 with adolescent samples; 14 young adult). For adolescents, ten studies reported no change in use prevalence associated with legalization, six reported a decrease, and seven reported an increase. Among young adults, most studies (8) showed an increase in at least one prevalence measure, four showed no change, and one showed a decrease. Only two adolescent and one young adult study examined cannabis use disorder, both adolescent studies showed an increase, and the young adult showed no change. The majority of studies had risk of bias. Recreational legalization may be associated with increases in prevalence of cannabis use in young adults while results for adolescents are mixed. Policymakers and practitioners should consider appropriate prevention and treatment options for young people.Trial Registration: PROSPERO #CRD42021276984.

Journey of Marijuana From "Folk Tales" to "Doors of Justice": A Comprehensive Review

This comprehensive review delves into the intricate journey of marijuana in India, tracing its historical and cultural significance from ancient times to the present day. Despite its deep-rooted presence in religious rituals, traditional medicine, and cultural festivities, marijuana faces stringent prohibition under the Narcotic Drugs and Psychotropic Substances Act 1985. This review critically examines the current legal framework, highlighting its societal impacts and limitations. Through an evidence-based analysis, it advocates for a reevaluation of marijuana laws to align with contemporary realities, promoting public health, social equity, and economic development. By envisioning a future of evidence-based regulation and innovation, India can unlock the full potential of marijuana as a "miracle crop" for the betterment of its people and society.

Cannabis and children: risk mitigation strategies for edibles

In the era of (re)legalisation of medicinal and recreational cannabis, accidental and intentional exposure to edibles, cannabis-infused food products, has increased substantially. However, there is particular concern regarding younger age groups. Most concerning is the increase in hospitalisations. According to a study by Myran et al. (1), provinces in Canada, where the sale of edibles is permitted, saw an increase in paediatric poisonings due to unintentional consumption of edibles. Similar trends have been observed in "legalised states" in the US, such as Colorado (2). The impact of using cannabis at an early age, but particularly the impact of accidental exposure to high THC quantities, may have negative mental or physical health outcomes. Whilst regulatory restrictions vary significantly from one legalised region to another, it is difficult to identify a best practice. The aim of this study is to identify and discuss new and existing risk mitigation strategies to give guidance to policymakers. Furthermore, practical aspects, such as compliance (e.g. audits by authorities), are discussed. It is noted that edibles have been around much longer than recent political attempts to regulate them.

Behavioral economic analysis of legal and illegal cannabis demand in Spanish young adults with hazardous and non-hazardous cannabis use

BACKGROUND

In October 2021, a legal framework that regulates cannabis for recreational purposes in Spain was proposed, but research on its potential impacts on cannabis use is currently limited. This study examined the reliability and discriminant validity of two Marijuana Purchase Tasks (MPTs) for measuring hypothetical legal and illegal cannabis demand, and to examine differences in demand of both commodities in young adults at hazardous vs. non-hazardous cannabis use risk levels.

METHODS

A total of 171 Spanish young adults [Mage = 19.82 (SD = 1.81)] with past-month cannabis use participated in a cross-sectional study from September to November 2021. Two 27-item MPTs were used to estimate hypothetical demand for legal and illegal cannabis independently. The Cannabis Use Disorder Identification Test (CUDIT-R) was used to assess hazardous cannabis use and test for discriminant validity of the MPTs. Reliability analyses were conducted using Classical Test Theory (Cronbach's alpha) and Item Response Theory (Item Information Functions).

RESULTS

The MPT was reliable for measuring legal (α = 0.94) and illegal (α = 0.90) cannabis demand. Breakpoint (price at which demand ceases), and Pmax (price associated with maximum expenditure) were the most sensitive indicators to discriminate participants with different levels of the cannabis reinforcing trait. No significant differences between legal and illegal cannabis demand in the whole sample were observed, but hazardous vs. non-hazardous users showed higher legal and illegal demand, and decreased Breakpoint and Pmax if cannabis were legal vs illegal.

CONCLUSION

The MPT exhibits robust psychometric validity and may be useful to inform on cannabis regulatory science in Spain.

Cannabis reduction among adolescents as spillover from successful tobacco control

BACKGROUND

National programs that reduce adolescent cannabis use warrant renewed attention in light of current discussions to reform cannabis legislation, including the possibility of legalization for recreational use. This study measures the size of a decrease in a country's prevalence of adolescent cannabis use that accompanies a decrease in its prevalence of adolescents who had ever smoked a cigarette.

METHODS

Data are from the European School Survey Project on Alcohol and Other Drugs (ESPAD), which is a collaborative effort of more than 40 European countries to surveil adolescent substance use. This study uses data from the seven survey administrations in 1995, 1999, 2003, 2007, 2011, 2015, and 2019. The main analysis is a fixed-effect regression analysis of country-level, four-year changes in adolescent lifetime cannabis use prevalence on country-level, four-year changes in adolescent lifetime cigarette use prevalence.

RESULTS

Decreases in the national prevalence of adolescents who had ever smoked a cigarette were accompanied by decreases half as large in national prevalence of adolescent lifetime cannabis use.

CONCLUSION

For European countries considering the legalization of adult recreational cannabis use, tobacco control can offer a tool to help counter potential increases in cannabis use among adolescents.

Health, safety, and socioeconomic impacts of cannabis liberalization laws: An evidence and gap map

Background

Globally, cannabis laws and regulations are rapidly changing. Countries are increasingly permitting access to cannabis under various decriminalization, medicalization, and legalization laws. With strong economic, public health, and social justice incentives driving these domestic cannabis policy reforms, liberalization trends are bound to continue. However, despite a large and growing body of interdisciplinary research addressing the policy-relevant health, safety, and socioeconomic consequences of cannabis liberalization, there is a lack of robust primary and systematic research that comprehensively investigates the consequences of these reforms.

Objectives

This evidence and gap map (EGM) summarizes the empirical evidence on cannabis liberalization policies. Primary objectives were to develop a conceptual framework linking cannabis liberalization policies to relevant outcomes, descriptively summarize the empirical evidence, and identify areas of evidence concentration and gaps.

Search Methods

We comprehensively searched for eligible English-language empirical studies published across 23 academic databases and 11 gray literature sources through August 2020. Additions to the pool of potentially eligible studies from supplemental sources were made through November 2020.

Selection Criteria

The conceptual framework for this EGM draws upon a legal epidemiological perspective highlighting the causal effects of law and policy on population-level outcomes. Eligible interventions include policies that create or expand access to a legal or decriminalized supply of cannabis: comprehensive medical cannabis laws (MCLs), limited medical cannabidiol laws (CBDLs), recreational cannabis laws (RCLs), industrial hemp laws (IHLs), and decriminalization of cultivations laws (DCLs). Eligible outcomes include intermediate responses (i.e., attitudes/behaviors and markets/environments) and longer-term consequences (health, safety, and socioeconomic outcomes) of these laws.

Data Collection and Analysis

Both dual screening and dual data extraction were performed with third person deconfliction. Primary studies were appraised using the Maryland Scientific Methods Scale and systematic reviews were assessed using AMSTAR 2.

Main Results

The EGM includes 447 studies, comprising 438 primary studies and nine systematic reviews. Most research derives from the United States, with little research from other countries. By far, most cannabis liberalization research focuses on the effects of MCLs and RCLs. Studies targeting other laws-including CBDLs, IHLs, and DCLs-are relatively rare. Of the 113 distinct outcomes we documented, cannabis use was the single most frequently investigated. More than half these outcomes were addressed by three or fewer studies, highlighting substantial evidence gaps in the literature. The systematic evidence base is relatively small, comprising just seven completed reviews on cannabis use (3), opioid-related harms (3), and alcohol-related outcomes (1). Moreover, we have limited confidence in the reviews, as five were appraised as minimal quality and two as low quality.

Authors’ Conclusions

More primary and systematic research is needed to better understand the effects of cannabis liberalization laws on longer-term-and arguably more salient-health, safety, and socioeconomic outcomes. Since most research concerns MCLs and RCLs, there is a critical need for research on the societal impacts of industrial hemp production, medical CBD products, and decriminalized cannabis cultivation. Future research should also prioritize understanding the heterogeneous effects of these laws given differences in specific provisions and implementation across jurisdictions.

The Compassion Club: A New Proposal for Transformation of Tobacco Retail

INTRODUCTION

One major assumption in the current tobacco industry is the distribution of tobacco products through a system of commercial for-profit retail. However, other models of distribution that do not rely on this mechanism exist.

AIMS AND METHODS

In this review, we examine the potential of a nonprofit Compassion Club model and discuss how the current existence of independent vape stores might provide the infrastructure to allow the transformation of tobacco distribution.

RESULTS

Compassion Clubs exist internationally with different levels of regulation and legality and have generally been focused on the distribution of illegal drugs or hard-to-access pharmaceuticals. They provide access to drugs for existing users, limit access by novices, limit negative impacts from illicit markets, and provide social support focused on reducing harms associated with drug use.

CONCLUSIONS

With decreasing prevalence of tobacco use in many countries and growing interest in a tobacco endgame, a Compassion Club model of distribution could help transition tobacco away from the model of commercial widely available distribution. More work is needed to develop the regulations and policies that might guide a compassion club model.

IMPLICATIONS

Compassion clubs are a model for the distribution of psychoactive substances that are focused on harm reduction and social support rather than profit. There has been little discussion about the possibility that this promising model could be applied to help transform the tobacco industry. Many independent vape stores already demonstrate aspects of the compassion club model that could be used to support a transition.

The impact of legal cannabis availability on cannabis use and health outcomes: A systematic review

BACKGROUND

For alcohol, regulating availability is an effective way to reduce consumption and harm. Similarly, the higher availability of medical cannabis dispensaries has been linked to increased cannabis consumption and harm. For recreational cannabis markets, such a link is suspected but still poorly understood.

METHODS

A systematic literature review (PROSPERO registration number 342357) was conducted on 1 July 2022 in common libraries (Medline, Web of Science, PsycInfo, Psyndex, CINAHL, Embase, SCOPUS, Cochrane) for publications since 2012. Studies linking variations in the availability of legal cannabis products to behavioral outcomes (cannabis use or related health indicators) were included, while studies focusing solely on the legalization of medical cannabis were excluded. The risk of bias was assessed using an adapted version of the Newcastle-Ottawa-Scale.

RESULTS

After screening n = 6,253 studies, n = 136 were selected for full-text review, out of which n = 13 met the inclusion criteria, reporting on n = 333,550 study participants and n = 855,630 presentations to emergency departments. All studies were conducted in North America, with the majority from Western US states. Using longitudinal (n = 1), cross-sectional (n = 4), or repeated cross-sectional (n = 8) study designs, an increased availability of legal cannabis was linked to increased current cannabis use and health-related outcomes (vomiting, psychosis, or cannabis-involved pregnancies), regardless of the indicator employed to measure availability (proximity or density) among both adults and adolescents. The positive correlation between cannabis availability and consumption is most pronounced among those groups who have been less exposed to cannabis before legalization. The association between the availability of legal cannabis and risky use indicators was less consistent.

CONCLUSIONS

Groups who have been least exposed to cannabis before legalization may be most susceptible to increased availability. In jurisdictions with legal cannabis markets, restrictions on the number of legal cannabis retailers, especially in densely populated areas, appear warranted.

The international regime of drug control may violate the human right to life and security

Critics of the international regime of drug control have often pointed to its criminogenic effects, maintaining that drug criminalization gives rise to a profitable illicit drugs market which in turn sustains organized crime networks. Here I will expand upon this critique to argue that the violent crime resulting from the drug criminalization regime may constitute a violation of the human right to life and security. To support this argument, I will discuss the extent to which policy makers and the citizens who empower them may stand morally responsible for unintended but foreseeable consequences of the policies they implement. I will note that a north-south imbalance is at play: while the Global North has been the driving force behind the criminalization regime, the violent criminality entailed by the regime of drug control has impacted the Global South most strongly.

Cannabis policy in The Netherlands: Rationale and design of an experiment with a controlled legal ('closed') cannabis supply chain

Since the Dutch tolerance policy, allowing the purchase of cannabis in 'coffeeshops', is associated with problems of public order and safety as well as health risks, there has been a long debate about legalisation of cannabis production and supply. It was therefore decided to conduct an experiment with a controlled legal ('closed') cannabis supply chain for recreational use. This is of international relevance in view of the current illegal cannabis exports from the Netherlands, the importance of sharing knowledge about the effectiveness of cannabis policies, and the accumulation of evidence needed to evaluate and update international treaties. Here we describe and discuss the background, general approach and design of the experiment. An independent expert committee elaborated how the closed chain will operate and be evaluated, based on the experience with the medicinal cannabis chain, and round table discussions with stakeholders (mayors, coffeeshop owners, cannabis consumers, growers, regulators, scientists, and addiction experts). Ten trusted cannabis growers are contracted to produce and supply cannabis to the coffeeshops in intervention municipalities, with product quality control, law enforcement against criminal interference, and preventive efforts to reduce health risks being implemented. No changes will be made in the cannabis supply to the coffeeshops in participating control municipalities. A process evaluation will assess whether the chain from production to sale in the intervention municipalities was really closed. In a quasi-experimental study comparing intervention and control municipalities, the chain's effects on public health, cannabis-related crime, safety and public nuisance will be estimated. The fieldwork period is expected to start early 2024 and will take four years, including reporting to the government and parliament. These will then decide whether and what further steps towards legalisation of the production and supply of cannabis will be taken.

The clouded debate: A systematic review of comparative longitudinal studies examining the impact of recreational cannabis legalization on key public health outcomes

Background

Ineffective cannabis regulatory frameworks such as prohibition have sparked interest in alternative solutions to reduce individual and societal harms. While it has been suggested that the recreational legalization process has yielded early successes, the relatively recent implementation of the novel policies has provided a modest time frame for a truly thorough establishment and assessment of key population-level indicators. The following systematic review focuses on identifying the downstream public health sequelae of cannabis legalization policies, including parameters such as cannabis consumption rates, hospitalization rates, vehicular accidents and fatalities, criminal activity, and suicidal behaviors, as well as other substance use trends.

Methods

An exhaustive search of the MEDLINE and Google Scholar databases were performed to identify high-quality (1) longitudinal studies, which (2) compared key public health outcomes between regions which had and had not implemented recreational cannabis legalization (RML) policies, (3) using distinct databases and/or time frames. Thirty-two original research articles were retained for review.

Results

Adult past-month cannabis consumption (26+ years) seems to have significantly increased following RML, whereas young adult (18-26 years) and adolescent (12-17 years) populations do not show a significant rise in past-month cannabis use. RML shows preliminary trends in increasing service use (such as hospitalizations, emergency department visits, or poisonings) or vehicular traffic fatalities. Preliminary evidence suggests that RML is related to potential increases in serious/violent crimes, and heterogeneous effects on suicidal behaviors. While the research does not illustrate that RML is linked to changing consumptions patterns of cigarette, stimulant, or opioid use, alcohol use may be on the rise, and opioid prescribing patterns are shown to be significantly correlated with RML.

Conclusion

The current data supports the notion that RML is correlated with altered cannabis consumption in adults, potentially increased criminal activity, and a decline in opioid quantities and prescriptions provided to patients. Future work should address additional knowledge gaps for vulnerable populations, such as individuals with mental health problems or persons consuming cannabis frequently/at higher THC doses. The effects of varying legalization models should also be evaluated for their potentially differing impacts on population-level outcomes.

Short-Term Effects of Recreational Cannabis Legalization on Youth Cannabis Initiation

PURPOSE

As recreational cannabis is legalized, it is critical to know the impacts of legalization on youth cannabis use. Existing research generates conflicting results and does not shed light on channels of effects. This study investigates the impacts of legalization on youth cannabis initiation and overall cannabis use prevalence.

METHODS

We used Interrupted Time Series design and data from nationally-representative repeated cross-sectional Canadian surveys spanning 16 years. The primary outcomes were cannabis initiation rates and cannabis use prevalence among youths. The secondary outcomes were self-reported age of first cannabis use, ease of cannabis access, and perception of cannabis harm among youths.

RESULTS

After legalization, cannabis initiation rate among youths was 2.7 percentage points (95% confidence interval: 1.7-3.7; p < .01) or 69% higher, although there was no significant increase in the overall prevalence of cannabis use. Furthermore, there was a 4-month delay in the average age of first cannabis use among youths aged 17-18 years (95% confidence interval: 2.6-5.5 months; p < .01). The legalization was associated with greater perception of cannabis harm but also easier access to cannabis.

DISCUSSION

The impacts of legalization on youth cannabis use after 1 year are mixed. Although we observed an increase in cannabis initiation among youths who had never used cannabis, there was no change in the overall prevalence of cannabis use, implying a possible offsetting increase in cannabis cessation among existing users. To achieve legalization's goal of reducing youth cannabis use, policy measures are needed to curb youth cannabis access and initiation.

Legalizing Harmful Drugs: Government Participation and Optimal policies

We are currently witnessing a shift in the approach to combat traffic and consumption of illegal harmful drugs, being cannabis legalization a prominent example. In this paper, we study how to optimally regulate the market for cannabis, in a setting where consumers differ in their utility from consumption of the psychoactive component of cannabis, THC, and suffer from misperception of the health damage it causes. We analyze this problem through a vertical differentiation model, where a black market firm and a public firm compete in prices and qualities (THC content). A paternalistic government would like to correct for the misperceived health damage caused by cannabis consumption, as well as to reduce the size of the black market. It is the undesirability of black market profits what explains that the first-best allocation cannot be decentralized. We find two possible equilibria, depending on whether the public firm serves those consumers with the highest or lowest willingness to pay for quality. Paradoxically, when the public firm serves those consumers with higher taste for THC, a lower average health damage is achieved together with a better economic result for the public firm.

Does recreational cannabis legalization change cannabis use patterns? Evidence from secondary school students in Uruguay

BACKGROUND AND AIMS

In 2013, Uruguay became the first country to legalize and regulate the production and distribution of cannabis for recreational use. We measured whether Uruguay's non-commercial model of recreational cannabis legalization was associated with changes in the prevalence of risky and frequent cannabis use among secondary school students.

DESIGN

We used data from repeated cross-sectional surveys of secondary students in Uruguay and Chile (2007-2018). Using a difference-in-difference approach, we evaluated changes in the prevalence of past-year, past-month, any risky and frequent cannabis use following enactment (2014) and implementation (2016) of cannabis legalization among the full sample of secondary students and among students who reported past-year/month use. We examined changes separately for students ages 12 to 17, and students for whom cannabis became legally accessible, ages 18 to 21.

SETTING

Uruguay and Chile (2007-2018).

PARTICIPANTS

Secondary school students in 8th, 10th and 12th grade (n = 204 730).

MEASUREMENTS

Past-year and past-month cannabis use; any risky cannabis use measured with the Cannabis Abuse Screening Test (CAST); and frequent cannabis use (10+ days in the past-month).

FINDINGS

We found a decrease in past-year and past-month use following enactment or implementation. Among students ages 18 to 21, post-enactment, we observed a transitory increase in 2014 that decreased thereafter for: any risky use among those who reported past-year use (prevalence difference [PD] = 13.5%; 95% CI: 2.0, 24.9), frequent use in the full sample (PD = 4.5%; 95% CI: 1.0, 8.1), and frequent use among those who reported past-month use (PD = 16.8%; 95% CI: 1.9, 31.8).

CONCLUSION

The legalization of recreational cannabis in Uruguay was not associated with overall increases in either past-year/past-month cannabis use or with multi-year changes in any risky and frequent cannabis use among young people.

Cannabis smoking increases the risk of suicide ideation and suicide attempt in young individuals of 11-21 years: A systematic review and meta-analysis

BACKGROUND

Cannabis is the most frequently consumed drug around the world. Its use has been associated with increased suicide behaviors; nonetheless, the association of cannabis smoking and suicide behaviors in adolescents has not yet been established. The aim of this systematic review and meta-analysis was to evaluate the risk of suicide attempt, suicidal ideation or suicide planning in individuals of 11-21 years of age who smoke cannabis.

METHODS

We performed an online searched using PubMed, EBSCO and Science Direct databases, up to July 2021. We calculated odds ratio with 95% confidence intervals to evaluate the association between suicide attempt, suicidal ideation or suicide planning and cannabis smoking in individuals of 11-21 years of age.

RESULTS

Twenty studies reported suicide attempts in 34,859 young individuals, suicidal ideation in 26, 937 individuals, and suicide planning in 9054 young individuals. We found an increased risk of suicide attempt in cannabis smokers than in non-cannabis users (OR: 2.33; 95% CI: 1.78-3.05; Z p value; <0.0001; I² = 97.12%), as well as a significant association between cannabis smoking and suicidal ideation (OR: 2.04; 95%CI: 1.64-2.53; Z p value: <0.001; I²: 94.88) and suicide planning (OR: 1.674; 95% CI: 1.554-1.804; Z p value: 0.000; I²: 92.609). Subgroup analyses showed that American teens have an increased risk of suicidal ideation; the meta-regression analysis revealed that age was negatively associated with the risk of suicide attempt.

CONCLUSIONS

This meta-analysis shows that cannabis smoking increased the risk of suicide attempt, suicidal ideation and suicide planning in young individuals of 11-21 years of age. The high risk of suicide behaviors could vary depending on the population studied; therefore, more studies are necessary to corroborate the risk of presenting suicide behaviors in individuals of 11-21 years of age who smoke cannabis.

Cannabis legalization and traffic injuries: exploring the role of supply mechanisms

BACKGROUND AND AIM

In Uruguay, residents age 18 and older seeking legal cannabis must register with the government and choose one of three supply mechanisms: self-cultivation, non-profit cannabis clubs or pharmacies. This is the first paper to measure the association between type of legal cannabis supply mechanism and traffic crashes involving injuries.

DESIGN

Ecological study using ordinary least squares regression to examine how department-level variation in registrations (overall and by type) is associated with traffic crashes involving injuries.

SETTING

Uruguay.

CASES

532 department-quarters.

MEASUREMENTS

Quarterly cannabis registration counts at the department level and incident-level traffic crash data were obtained from government agencies. The analyses controlled for department-level economic and demographic characteristics and, as a robustness check, we included traffic violations involving alcohol for departments reporting this information. Department-level data on crashes, registrations and alcohol violations were denominated by the number of residents ages 18 and older.

FINDINGS

From 2013 to 2019, the average number of registrations at the department-quarter level per 10 000 residents age 18 and older for self-cultivation, club membership and pharmacy purchasing were 17.7 (SD = 16.8), 3.6 (SD = 8.6), and 25.1 (SD = 50.4), respectively. In our multivariate regression analyses, we did not find a statistically significant association between the total number of registrations and traffic crashes with injuries (β = -0.007; P = 0.398; 95% CI = -0.023, 0.01). Analyses focused on the specific supply mechanisms found a consistent, positive and statistically significant association between the number of individuals registered as self-cultivators and the number of traffic crashes with injuries (β = 0.194; P = 0.008; 95% CI = 0.058, 0.329). Associations for other supply mechanisms were inconsistent across the various model specifications.

CONCLUSIONS

In Uruguay, the number of people allowed to self-cultivate cannabis is positively associated with traffic crashes involving injuries. Individual-level analyses are needed to assess better the factors underlying this association.

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.

Trends in the sequence of initiation of alcohol, tobacco, and marijuana use among adolescents in Argentina and Chile from 2001 to 2017

BACKGROUND

Variation in drug policies, norms, and substance use over time and across countries may affect the normative sequences of adolescent substance use initiation. We estimated relative and absolute time-varying associations between prior alcohol and tobacco use and adolescent marijuana initiation in Argentina and Chile. Relative measures quantify the magnitude of the associations, whereas absolute measures quantify excess risk.

METHODS

We analyzed repeated, cross-sectional survey data from the National Surveys on Drug Use Among Secondary School Students in Argentina (2001-2014) and Chile (2001-2017). Participants included 8th, 10th, and 12th grade students (N = 680,156). Linear regression models described trends over time in the average age of first use of alcohol, tobacco, and marijuana. Logistic regression models were used to estimate time-varying risk ratios and risk differences of the associations between prior alcohol and tobacco use and current-year marijuana initiation.

RESULTS

Average age of marijuana initiation increased and then decreased in Argentina and declined in Chile. In both countries, the relative associations between prior tobacco use and marijuana initiation weakened amid declining rates of tobacco use; e.g., in Argentina, the risk ratio was 19.9 (95% CI: 9.0-30.8) in 2001 and 11.6 (95% CI: 9.0-13.2) in 2014. The relative association between prior alcohol use and marijuana initiation weakened Chile, but not in Argentina. On the contrary, risk differences (RD) increased substantially across both relationships and countries, e.g., in Argentina, the RD for tobacco was 3% (95% CI: 0.02-0.03) in 2001 and 12% (95% CI: 0.11-0.13) in 2014.

CONCLUSION

Diverging trends in risk ratios and risk differences highlight the utility of examining multiple measures of association. Variation in the strength of the associations over time and place suggests the influence of environmental factors. Increasing risk differences indicate alcohol and tobacco use may be important targets for interventions to reduce adolescent marijuana use.

Changes in cannabis policy and prevalence of recreational cannabis use among adolescents and young adults in Europe-An interrupted time-series analysis

BACKGROUND

Cannabis policy varies greatly across European countries, but evidence of how such policy impacts on recreational cannabis use among young people is conflicting. This study aimed to clarify this association by investigating how changes in cannabis legislation influenced cannabis use.

METHODS

Available data on self-reports of recreational cannabis use among individuals aged 15-34 years was retrieved from EMCDDA. Information on cannabis policy changes was categorized as more lenient (decriminalisation or depenalisation) or stricter (criminalisation, penalisation). Countries that had implemented changes in cannabis legislation or had information on prevalence of use for at least eight calendar years, were eligible for inclusion. We used interrupted time-series linear models to investigate changes in country-specific trajectories of prevalence over calendar time and in relation to policy changes.

RESULTS

Data from Belgium, Czech Republic, Germany, Italy, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden and United Kingdom, for 1994-2017 was available for analyses. Cannabis use varied considerably over the study period and between countries. On average, use was stable or weakly increasing in countries where legislation was not changed or changed at the extremes of the study period (+0.08 percent per year [95% CI -0.01, 0.17 percent]). In contrast, the pooled average use decreased after changes in legislation, regardless of whether it had become more lenient (-0.22 [-1.21, 0.77]) or stricter (-0.44 [-0.91, 0.03]).

CONCLUSIONS

Our findings do not support any considerable impact of cannabis legislation on the prevalence of recreational cannabis use among youth and young adults in Europe.

Effects of Risk Perception and Accessibility on Cannabis Use among Young Population in Spain: Findings from the 2016 National Survey (ESTUDES)

BackgroundCannabis use in the young population has undergone a significant increase in Europe. Empirical assessments of individual and contextual mediating variables in relation to cannabis use are informative for prevention actions and have yet to be conducted in Spain. Objectives: This study used the 2016 National Survey on Drug Use in Secondary Education in Spain (ESTUDES) to inform on potentially relevant cannabis prevention targets. We examined individual variables (sex, age, and cannabis risk perception), past 30-day legal and illicit substance use, substance-free activities, and contextual factors (perceived accessibility to cannabis) associated to past 30-day cannabis use. Methods: Data were drawn from 35,369 adolescents (% females: 50.1). Structural equation modeling (SEM) was implemented to identify predictors of cannabis use, and indirect paths were tested via bootstrapping to examine the mediating effects of cannabis risk perception and accessibility. Results: Demographics (male sex, higher age), and past 30-day tobacco, alcohol, and illicit substance use were associated with past 30-day cannabis use. Frequency of past-year engagement in hobbies and reading did also predict past 30-day cannabis use. The mediators worked on most of the relationships examined, except for hobbies and illegal substance use in the case of accessibility and reading and hobbies in the case of risk perception. Conclusions/importance: Cannabis use is more likely to emerge in the event of low risk perception and high accessibility. Lower frequency of past year reading and higher engagement in some hobbies that are often carried out alone represent risk factors, which could potentially influence prevention programs.

Adolescent cannabis experimentation and unemployment in young to mid-adulthood: Results from the French TEMPO Cohort study

BACKGROUND

France accounts for one of the highest levels of recreational cannabis use, with almost 40% of youth aged 17 reporting having experimented with cannabis. We investigated the impact of early cannabis experimentation (defined as first-time use ≤ 16 years) on future probability of unemployment in young to mid-adulthood using a longitudinal, community sample over the span of 9 years.

METHODS

Data were obtained from the French TEMPO Cohort study, set up in 2009 among young adults aged 22-25 years old. Participants who reported information on age of cannabis experimentation and employment status in at least one study wave (2009, 2011, 2015 and 2018) were included in the statistical analyses (N = 1487, 61.2% female).

RESULTS

In A-IPW-adjusted analyses, early cannabis experimenters (≤ 16 years) had 1.71 (95% CI: 1.46-2.02) times higher odds of experiencing unemployment compared to late cannabis experimenters (> 16 years) and 2.40 (95% CI: 2.00 - 2.88) times higher odds of experiencing unemployment compared to non-experimenters. Late cannabis experimenters experienced 1.39 (95% CI: 1.17-1.68) times higher odds of being unemployed compared to non-experimenters, and early cannabis experimenters experienced 3.84 (95%CI: 2.73-5.42) times higher odds of experiencing long-term unemployment (defined as unemployed at least twice) compared to non-experimenters.

CONCLUSIONS

Participants who ever used cannabis, especially at or before the age of 16, had higher odds of experiencing unemployment, even when accounting for many psychological, academic and family characteristics which preceded cannabis initiation.

Gas Chromatographic Fingerprint Analysis for the Comparison of Seized Cannabis Samples

Cannabis sativa L. is widely used as recreational illegal drugs. Illicit Cannabis profiling, comparing seized samples, is challenging due to natural Cannabis heterogeneity. The aim of this study was to use GC-FID and GC-MS herbal fingerprints for intra (within)- and inter (between)-location variability evaluation. This study focused on finding an acceptable threshold to link seized samples. Through Pearson correlation-coefficient calculations between intra-location samples, 'linked' thresholds were derived using 95% and 99% confidence limits. False negative (FN) and false positive (FP) error rate calculations, aiming at obtaining the lowest possible FP value, were performed for different data pre-treatments. Fingerprint-alignment parameters were optimized using Automated Correlation-Optimized Warping (ACOW) or Design of Experiments (DoE), which presented similar results. Hence, ACOW data, as reference, showed 54% and 65% FP values (95 and 99% confidence, respectively). An additional fourth root normalization pre-treatment provided the best results for both the GC-FID and GC-MS datasets. For GC-FID, which showed the best improved FP error rate, 54 and 65% FP for the reference data decreased to 24 and 32%, respectively, after fourth root transformation. Cross-validation showed FP values similar as the entire calibration set, indicating the representativeness of the thresholds. A noteworthy improvement in discrimination between seized Cannabis samples could be concluded.

An overview of select cannabis use and supply indicators pre- and post-legalization in Canada

Background

Canada implemented the legalization and regulation of non-medical cannabis use, production and sale in 2018 aiming to improve public health and safety. While outcomes from legalization reforms in other jurisdictions mostly rely on US-based data have been assessed to be mixed, Canadian data are only emerging. We compiled select population-level data on key indicators to gauge initial developments from pre- to post-legalization of cannabis in Canada.

Methods

We examined indicators data focusing on the following topics: prevalence of cannabis use, frequency of use, methods/products of consumption, driving after cannabis use, and cannabis sourcing. Indicator data were obtained mostly from national and some provincial population surveys. Prevalence or percentages for the indicators pre- and post-legalization (e.g., 2017- 2020), including confidence intervals were reported, with changes noted, as available in and indicated by the data sources.

Results

Data suggested selected increases in cannabis use prevalence, mostly among mid- and older- but possibly also younger (e.g., under legal use age) users. Frequency of use and driving after cannabis use among active users do not appear to have changed. Methods of cannabis use show diversifying trends, with decreases in smoking and increases in alternatives use modes (e.g., edibles, vaping). There is a clearly increasing trend towards accessing cannabis from legal sources among adults, while under-legal-use-age youth do not appear to experience heightened barriers to obtaining cannabis in legalization contexts.

Conclusions

Preliminary indicators on cannabis legalization in Canada show a mixed picture, some similar to US-based developments. While some use increases are observed, these do not necessarily represent indications of increases in cannabis-related harm, also since key (e.g., hospitalization or injury) data are lacking to date. There is a gradual embracing of legal supply sources of cannabis among users, which can be expected to serve public health and safety objectives. At the same time, cannabis use and access among under-age users as a principally vulnerable group do not appear to be hindered or reduced by legalization.

Early Consumption of Cannabinoids: From Adult Neurogenesis to Behavior

The endocannabinoid system (ECS) is a crucial modulatory system in which interest has been increasing, particularly regarding the regulation of behavior and neuroplasticity. The adolescent-young adulthood phase of development comprises a critical period in the maturation of the nervous system and the ECS. Neurogenesis occurs in discrete regions of the adult brain, and this process is linked to the modulation of some behaviors. Since marijuana (cannabis) is the most consumed illegal drug globally and the highest consumption rate is observed during adolescence, it is of particular importance to understand the effects of ECS modulation in these early stages of adulthood. Thus, in this article, we sought to summarize recent evidence demonstrating the role of the ECS and exogenous cannabinoid consumption in the adolescent-young adulthood period; elucidate the effects of exogenous cannabinoid consumption on adult neurogenesis; and describe some essential and adaptive behaviors, such as stress, anxiety, learning, and memory. The data summarized in this work highlight the relevance of maintaining balance in the endocannabinoid modulatory system in the early and adult stages of life. Any ECS disturbance may induce significant modifications in the genesis of new neurons and may consequently modify behavioral outcomes.

Cannabis Policy Changes and Adolescent Cannabis Use: Evidence from Europe

Cannabis accounts for the largest share of the illicit drug market, with a high prevalence of use even among adolescents. To tackle this longstanding problem, many kinds of reforms to national cannabis control policies have been implemented in Europe, but their effectiveness is still unclear. This paper analyses the association between selected categories of cannabis policy reforms and changes in perceived cannabis availability and patterns of use among adolescents. Data from 20 European countries across 15 years were drawn from a novel database of the European school Survey Project on Alcohol and other Drugs (ESPAD). Our analysis is based on a Difference-in-Differences design, which application is allowed by the fact that only thirteen out of the twenty countries included implemented policy changes. The results suggest that selected categories of reforms influence the availability and prevalence of cannabis use. In particular, some forms of restrictive intervention reduce the general prevalence of use and more liberal reforms seem linked to an increase in the share of students initiating use of cannabis. We find no evidence of an effect of policy changes on the share of frequent users, which are presumably those more likely to develop use-related health consequences.

Impact evaluations of drug decriminalisation and legal regulation on drug use, health and social harms: a systematic review

OBJECTIVES

To review the metrics and findings of studies evaluating effects of drug decriminalisation or legal regulation on drug availability, use or related health and social harms globally.

DESIGN

Systematic review with narrative synthesis.

DATA SOURCES

We searched MEDLINE, Embase, PsycINFO, Web of Science and six additional databases for publications from 1 January 1970 through 4 October 2018.

INCLUSION CRITERIA

Peer-reviewed articles or published abstracts in any language with quantitative data on drug availability, use or related health and social harms collected before and after implementation of de jure drug decriminalisation or legal regulation.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened titles, abstracts and articles for inclusion. Extraction and quality appraisal (modified Downs and Black checklist) were performed by one reviewer and checked by a second, with discrepancies resolved by a third. We coded study-level outcome measures into metric groupings and categorised the estimated direction of association between the legal change and outcomes of interest.

RESULTS

We screened 4860 titles and 221 full-texts and included 114 articles. Most (n=104, 91.2%) were from the USA, evaluated cannabis reform (n=109, 95.6%) and focussed on legal regulation (n=96, 84.2%). 224 study outcome measures were categorised into 32 metrics, most commonly prevalence (39.5% of studies), frequency (14.0%) or perceived harmfulness (10.5%) of use of the decriminalised or regulated drug; or use of tobacco, alcohol or other drugs (12.3%). Across all substance use metrics, legal reform was most often not associated with changes in use.

CONCLUSIONS

Studies evaluating drug decriminalisation and legal regulation are concentrated in the USA and on cannabis legalisation. Despite the range of outcomes potentially impacted by drug law reform, extant research is narrowly focussed, with a particular emphasis on the prevalence of use. Metrics in drug law reform evaluations require improved alignment with relevant health and social outcomes.