Trends in the use of cannabis products in Canada and the USA, 2018 - 2020: Findings from the International Cannabis Policy Study.

BACKGROUND AND AIMS: There is little information on consumption patterns across the diverse range of cannabis product types. This paper examines trends in consumption patterns in Canada and the United States (US) between 2018-2020. DESIGN: Repeat cross-sectional surveys were conducted as part of the International Cannabis Policy Study online survey in 2018 (n=27,024), 2019 (n=45,426), and 2020 (n=45,180). SETTING: Respondents were recruited from commercial panels in Canada and US states that had and had not legalized non-medical cannabis (US 'legal' and 'illegal' states, respectively). PARTICIPANTS: Respondents were male and female participants aged 16-65 years. MEASUREMENTS: Data on frequency and consumption amounts were collected for nine types of cannabis products, including dried flower and processed products (e.g., oils and concentrates). Consumers were also asked about mixing cannabis with tobacco. Socio-demographic information was collected. FINDINGS: Dried flower was the most commonly used product, although use in the past 12 months declined between 2018 and 2020 in Canada (81% to 73%), US legal (78% to 72%) and illegal states (81% to 76%; p<0.05 for all). Prevalence of past 12-month use increased for virtually all other product forms, although prevalence of daily use remained stable across years. In 2020, edibles and vape oils were the most commonly used products after flower. Use of non-flower products was highest in US legal states, although similar trends were observed in all jurisdictions. Males were more likely to report using processed products, and vape oils were the most commonly processed product among 16-20-year-olds. Daily use of cannabis flower increased in US legal and illegal states, and average joint size increased across all jurisdictions over time. CONCLUSIONS: Dried flower remains the dominant product in Canada and the US; however, use of processed cannabis products has increased, with the largest increases observed in legal cannabis markets.

Lower-Risk Cannabis Use Guidelines (LRCUG) for reducing health harms from non-medical cannabis use: A comprehensive evidence and recommendations update.

BACKGROUND: Cannabis use is common, especially among young people, and is associated with risks for various health harms. Some jurisdictions have recently moved to legalization/regulation pursuing public health goals. Evidence-based 'Lower Risk Cannabis Use Guidelines' (LRCUG) and recommendations were previously developed to reduce modifiable risk factors of cannabis-related adverse health outcomes; related evidence has evolved substantially since. We aimed to review new scientific evidence and to develop comprehensively up-to-date LRCUG, including their recommendations, on this evidence basis. METHODS: Targeted searches for literature (since 2016) on main risk factors for cannabis-related adverse health outcomes modifiable by the user-individual were conducted. Topical areas were informed by previous LRCUG content and expanded upon current evidence. Searches preferentially focused on systematic reviews, supplemented by key individual studies. The review results were evidence-graded, topically organized and narratively summarized; recommendations were developed through an iterative scientific expert consensus development process. RESULTS: A substantial body of modifiable risk factors for cannabis use-related health harms were identified with varying evidence quality. Twelve substantive recommendation clusters and three precautionary statements were developed. In general, current evidence suggests that individuals can substantially reduce their risk for adverse health outcomes if they delay the onset of cannabis use until after adolescence, avoid the use of high-potency (THC) cannabis products and high-frequency/-intensity of use, and refrain from smoking-routes for administration. While young people are particularly vulnerable to cannabis-related harms, other sub-groups (e.g., pregnant women, drivers, older adults, those with co-morbidities) are advised to exercise particular caution with use-related risks. Legal/regulated cannabis products should be used where possible. CONCLUSIONS: Cannabis use can result in adverse health outcomes, mostly among sub-groups with higher-risk use. Reducing the risk factors identified can help to reduce health harms from use. The LRCUG offer one targeted intervention component within a comprehensive public health approach for cannabis use. They require effective audience-tailoring and dissemination, regular updating as new evidence become available, and should be evaluated for their impact.

Early evidence of the impact of cannabis legalization on cannabis use, cannabis use disorder, and the use of other substances: Findings from state policy evaluations.

Background: The past decade has seen unprecedented shifts in the cannabis policy environment, and the public health impacts of these changes will hinge on how they affect patterns of cannabis use and the use and harms associated with other substances.Objectives: To review existing research on how state cannabis policy impacts substance use, emphasizing studies using methods for causal inference and highlighting gaps in our understanding of policy impacts on evolving cannabis markets.Methods: Narrative review of quasi-experimental studies for how medical cannabis laws (MCLs) and recreational cannabis laws (RCLs) affect cannabis use and use disorders, as well as the use of or harms from alcohol, opioids, and tobacco.Results: Research suggests MCLs increase adult but not adolescent cannabis use, and provisions of the laws associated with less regulated supply may increase adult cannabis use disorders. These laws may reduce some opioid-related harms, while their impacts on alcohol and tobacco use remain uncertain. Research on RCLs is just emerging, but findings suggest little impact on the prevalence of adolescent cannabis use, potential increases in college student use, and unknown effects on other substance use.Conclusions: Research on how MCLs influence cannabis use has advanced our understanding of the importance of heterogeneity in policies, populations, and market dynamics, but studies of how MCLs relate to other substance use often ignore these factors. Understanding effects of cannabis laws requires greater attention to differences in short- versus long-term effects of the laws, nuances of policies and patterns of consumption, and careful consideration of appropriate control groups.

The impacts of potency, warning messages, and price on preferences for Cannabis flower products.

BACKGROUND: Recreational cannabis has been legalized in 11 states and Washington DC in the US. However, little is known about individual preferences for legal cannabis products. This study estimated the impacts of tetrahydrocannabinol (THC), cannabidiol (CBD), warning messages, and price on preferences for cannabis flowers. METHODS: A cross-sectional online survey with discrete choice experiments was implemented in October 2017. A sample of 2400 adults aged 21 years or older were recruited from 6 US states with recreational cannabis legalization, consisting of 1200 past-year nonusers and 1200 past-year users. Each respondent was randomly assigned to 12 discrete choice scenarios, each asking them to choose from an opt-out option and 3 cannabis flower products with varying levels in THC, CBD, warning messages, and price. The impacts of product attributes on individual choices were analyzed with nested logit regressions. RESULTS: Both cannabis nonusers and users preferred higher CBD and lower price. Users also preferred higher THC. The results on warning messages were mixed: graphic warning on drugged driving and text warning message had positive impacts on nonusers' and users' preferences for cannabis flowers, respectively, whereas FDA disapproval disclaimer had negative impacts on nonusers' preferences. Heterogeneities in preferences were revealed among nonusers by former use status and among users by reason of use. Particularly, medical cannabis users were not as responsive to THC as recreational cannabis users or dual users were. Regarding relative importance of the attributes, all respondents but medical cannabis users perceived price as the most important attribute (relative importance 51-64%), whereas medical cannabis users perceived CBD as the most important attribute (relative importance 47%). CONCLUSION: The findings indicated that product characteristics may have influences on US adults' choices of legal cannabis flower products and may deserve consideration for cannabis regulatory framework.

Do medical marijuana laws reduce addictions and deaths related to pain killers?

Recent work finds that medical marijuana laws reduce the daily doses filled for opioid analgesics among Medicare Part-D and Medicaid enrollees, as well as population-wide opioid overdose deaths. We replicate the result for opioid overdose deaths and explore the potential mechanism. The key feature of a medical marijuana law that facilitates a reduction in overdose death rates is a relatively liberal allowance for dispensaries. As states have become more stringent in their regulation of dispensaries, the protective value generally has fallen. These findings suggest that broader access to medical marijuana facilitates substitution of marijuana for powerful and addictive opioids.

Association of State Recreational Marijuana Laws With Adolescent Marijuana Use.

Importance: Historical shifts are occurring in marijuana policy. The effect of legalizing marijuana for recreational use on rates of adolescent marijuana use is a topic of considerable debate. Objective: To examine the association between the legalization of recreational marijuana use in Washington and Colorado in 2012 and the subsequent perceived harmfulness and use of marijuana by adolescents. Design, Setting, and Participants: We used data of 253 902 students in eighth, 10th, and 12th grades from 2010 to 2015 from Monitoring the Future, a national, annual, cross-sectional survey of students in secondary schools in the contiguous United States. Difference-in-difference estimates compared changes in perceived harmfulness of marijuana use and in past-month marijuana use in Washington and Colorado prior to recreational marijuana legalization (2010-2012) with postlegalization (2013-2015) vs the contemporaneous trends in other states that did not legalize recreational marijuana use in this period. Main Outcomes and Measures: Perceived harmfulness of marijuana use (great or moderate risk to health from smoking marijuana occasionally) and marijuana use (past 30 days). Results: Of the 253 902 participants, 120 590 of 245 065(49.2%) were male, and the mean (SD) age was 15.6 (1.7) years. In Washington, perceived harmfulness declined 14.2% and 16.1% among eighth and 10th graders, respectively, while marijuana use increased 2.0% and 4.1% from 2010-2012 to 2013-2015. In contrast, among states that did not legalize recreational marijuana use, perceived harmfulness decreased by 4.9% and 7.2% among eighth and 10th graders, respectively, and marijuana use decreased by 1.3% and 0.9% over the same period. Difference-in-difference estimates comparing Washington vs states that did not legalize recreational drug use indicated that these differences were significant for perceived harmfulness (eighth graders: % [SD], -9.3 [3.5]; P = .01; 10th graders: % [SD], -9.0 [3.8]; P = .02) and marijuana use (eighth graders: % [SD], 5.0 [1.9]; P = .03; 10th graders: % [SD], 3.2 [1.5]; P = .007). No significant differences were found in perceived harmfulness or marijuana use among 12th graders in Washington or for any of the 3 grades in Colorado. Conclusions and Relevance: Among eighth and 10th graders in Washington, perceived harmfulness of marijuana use decreased and marijuana use increased following legalization of recreational marijuana use. In contrast, Colorado did not exhibit any differential change in perceived harmfulness or past-month adolescent marijuana use following legalization. A cautious interpretation of the findings suggests investment in evidence-based adolescent substance use prevention programs in any additional states that may legalize recreational marijuana use.

The price elasticity of demand for heroin: Matched longitudinal and experimental evidence.

This paper reports estimates of the price elasticity of demand for heroin based on a newly constructed dataset. The dataset has two matched components concerning the same sample of regular heroin users: longitudinal information about real-world heroin demand (actual price and actual quantity at daily intervals for each heroin user in the sample) and experimental information about laboratory heroin demand (elicited by presenting the same heroin users with scenarios in a laboratory setting). Two empirical strategies are used to estimate the price elasticity of demand for heroin. The first strategy exploits the idiosyncratic variation in the price experienced by a heroin user over time that occurs in markets for illegal drugs. The second strategy exploits the experimentally induced variation in price experienced by a heroin user across experimental scenarios. Both empirical strategies result in the estimate that the conditional price elasticity of demand for heroin is approximately -0.80.

Developing public health regulations for marijuana: lessons from alcohol and tobacco.

Until November 2012, no modern jurisdiction had removed the prohibition on the commercial production, distribution, and sale of marijuana for nonmedical purposes-not even the Netherlands. Government agencies in Colorado and Washington are now charged with granting production and processing licenses and developing regulations for legal marijuana, and other states and countries may follow. Our goal is not to address whether marijuana legalization is a good or bad idea but, rather, to help policymakers understand the decisions they face and some lessons learned from research on public health approaches to regulating alcohol and tobacco over the past century.

Design considerations for legalizing cannabis: lessons inspired by analysis of California's Proposition 19.

AIMS: No modern jurisdiction has ever legalized commercial production, distribution and possession of cannabis for recreational purposes. This paper presents insights about the effect of legalization on production costs and consumption and highlights important design choices. METHODS: Insights were uncovered through our analysis of recent legalization proposals in California. The effect on the cost of producing cannabis is largely based on existing estimates of current wholesale prices, current costs of producing cannabis and other legal agricultural goods, and the type(s) of production that will be permitted. The effect on consumption is based on production costs, regulatory regime, tax rate, price elasticity of demand, shape of the demand curve and non-price effects (e.g. change in stigma). RESULTS: Removing prohibitions on producing and distributing cannabis will dramatically reduce wholesale prices. The effect on consumption and tax revenues will depend on many design choices, including: the tax level, whether there is an incentive for a continued black market, whether to tax and/or regulate cannabinoid levels, whether there are allowances for home cultivation, whether advertising is restricted, and how the regulatory system is designed and adjusted. CONCLUSIONS: The legal production costs of cannabis will be dramatically below current wholesale prices, enough so that taxes and regulation will be insufficient to raise retail price to prohibition levels. We expect legalization will increase consumption substantially, but the size of the increase is uncertain since it depends on design choices and the unknown shape of the cannabis demand curve.

Marijuana use and high school dropout: the influence of unobservables.

In this study, we reconsider the relationship between heavy and persistent marijuana use and high school dropout status. Using a unique prospective panel study of over 4500 7th grade students from South Dakota who are followed through high school, we developed propensity score weights to adjust for baseline differences found to exist before marijuana initiation occurs for most students (7th grade). We then used weighted logistic regression that incorporates these propensity score weights to examine the extent to which time-varying factors, including substance use, also influence the likelihood of dropping out of school. We found a positive association between marijuana use and dropping out (OR=5.6, RR=3.8), over half of which was explained by prior differences in observational characteristics and behaviors. The remaining association (OR=2.4, RR=1.7) became statistically insignificant when measures of cigarette smoking were included in the analysis. Because cigarette smoking is unlikely to seriously impair cognition, we interpret this result as evidence that the association between marijuana use and high school dropout is unlikely to be due to its adverse effects on cognition. We then explored which constructs drive this result, determining that they are time-varying parental and peer influences.

What we can--and cannot--expect from school-based drug prevention.

School-based drug prevention is a central component of drug control strategies. This paper assesses quantitatively its contributions in the United States from a social policy perspective. The social benefits per participant stemming from reduced drug use ( approximately $840 from tobacco, alcohol, cocaine and marijuana) appear to exceed the economic costs of running the programs ( approximately $150 per participant); while the benefits associated with reduced cocaine use alone ( approximately $300) exceed the costs, the corresponding figure for marijuana ( approximately $20) is small. Even if prevention reduced the use of other illicit drugs (e.g. heroin) by as much as it reduced use of cocaine, the majority of benefits would still stem from reductions in use of tobacco and alcohol, which has implications for how school-based drug prevention is funded and whether it is perceived more as a weapon in the war on illicit drugs or as a public health measure. Specific numeric results are subject to considerable uncertainty, but the basic character of the conclusions appears to be robust with respect to parameter uncertainty. The greatest uncertainties concern the permanence of prevention's effects and how to value instances of initiation being deferred but not completely prevented.

State medical marijuana laws: understanding the laws and their limitations.

Significant attention has been given to the debate regarding allowances for medical marijuana use since the 1996 California and Arizona ballot initiatives. State medical marijuana allowances, however, have existed since the mid-1970s. Much of the current debate stems from confusion about the various ways states approach the issue. In this paper, we present original legal research on current state medical marijuana laws identifying four different ways states statutorily enable the medical use of marijuana. We discuss the tension these approaches have with federal law as well as their implications regarding real access for patients. In addition, we present information on how a small number of states are trying to deal with the issue of access within the context of their medical marijuana laws, and discuss the implication of various supply approaches on the enforcement of other state marijuana laws.