Modes of Marijuana Consumption Among Colorado High School Students Before and After the Initiation of Retail Marijuana Sales for Adults

The impact of recreational cannabis legalization on youth: the Colorado experience

Over the past two decades, cannabis policies have liberalized in the United States, culminating in the legalization of recreational cannabis in Colorado and Washington state in 2012. This review will focus on the impact of recreational cannabis legalization in Colorado. While the prevalence of past-year and past-month cannabis use has remained relatively steady among adolescents post-legalization, the prevalence of young adult use has continued to rise. Cannabis products with increased potency have become more prevalent and widely used. There are concerns that the use of products with increased potency will increase risk for cannabis use and comorbid mental health disorders, particularly cannabis-induced psychosis and suicidal behavior, although more research is needed to fully understand the impact of high-potency products. Since the legalization of recreational cannabis, numerous additional public health concerns have emerged: unintentional overdoses requiring acute care visits, electronic vaping-associated lung injury, increased motor vehicle collisions related to cannabis consumption, and higher rates of cannabis use during pregnancy. Lessons learned from the first decade of cannabis legalization emphasize the need for research efforts to provide evidence-based guidelines, inform prevention strategies, and implement selective interventions for at-risk populations including youth, individuals with comorbid mental health disorders, and individuals who are pregnant.

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.

Associations between Oral Health and Cannabis Use among Adolescents and Young Adults: Implications for Orthodontists

Cannabis use is prevalent among adolescents and young adults in the US. Virtually all modes of cannabis consumption involve the oral cavity, and previous studies have linked cannabis use with poorer oral health. We sought to identify associations between cannabis use and various oral health outcomes and behaviors among individuals 12-25 years of age, and to discuss implications for orthodontists who largely interact with this age group over an extended period of treatment time. We examined data from patient electronic health records (N = 14,657) obtained between 2015 and 2021. Associations between lifetime and current self-reported cannabis use and several oral health outcomes or related behaviors that reflect periodontal health, caries status, oral lesions, and physical integrity of tooth structure and restorations were examined in a bivariable and multivariable manner, controlling for patient age, sex, and self-reported tobacco and alcohol use. Reporting lifetime cannabis use was associated with higher risk for having oral lesions (aPR = 1.41, 95% CI: 1.07-1.85), bruxism (aPR = 1.31, 95% CI: 1.09-1.58), and frequent consumption of sugary beverages and snacks (aPR = 1.27, 95% CI: 1.12-1.41). Reporting current cannabis use was associated with higher risk for oral lesions (aPR = 1.45, 95% CI: 1.03-2.06) and frequent consumption of sugary beverages and snacks (aPR = 1.26, 95% CI: 1.07-1.48). Cannabis users aged 12-25 are at increased risk for bruxism, oral lesions, and frequent consumption of sugary beverages and snacks. Orthodontists and other dental professionals should probe for drug use and be cognizant of increased risk for oral health problems in patients that report actively using cannabis.

Prevalence and use of cannabis products and routes of administration among youth and young adults in Canada and the United States: A systematic review

BACKGROUND

The current systematic review aimed to summarize the literature on the prevalence of routes of administration and cannabis products used among youth and young adults in Canada and the United States (US).

METHODS

Five academic databases were searched in April 2020 and February 2021. Peer-reviewed articles were included if they were a population-based quantitative observational study describing the prevalence of a cannabis product or route of administration among youth and young adults in Canada or the US. Risk of bias was assessed using Hoy and colleagues' risk of bias assessment tool. A narrative review was conducted.

RESULTS

Twenty-six studies were identified for the following routes of administration: smoking (n = 16), vaping (n = 21), dabbing (n = 3), oral (n = 13), topical (n = 1); and products: dried flower (n = 2), and concentrates (n = 8). Smoking had the highest prevalence rates among youth and young adults; however, rates of use appeared to reduce over time. Conversely, prevalence of vaping appeared to increase over time. Fewer studies focused on oral or dabbed cannabis but those that did reported prevalence estimates of approximately a third among recent cannabis consumers.

DISCUSSION

The heterogeneity of cannabis routes of administration restricted our ability to collate average prevalence estimates. In jurisdictions where non-medical cannabis is legal, policymakers should provide guidance and education to youth on each type of product and routes of administration.

OTHER

Funding for this study was provided by a Canadian Institutes of Health Research (PJT-153342). The current review was registered with PROSPERO (CRD42020169275).

Copycat and lookalike edible cannabis product packaging in the United States

BACKGROUND

Recent media reports have highlighted copycat/lookalike cannabis edibles as a public health concern. No empirical papers have described this phenomenon.

METHODS

From May 2020-August 2021, we collected photos of cannabis products via an online survey of cannabis users and through personal contacts. Copycat/lookalike products are defined as those that use the same or similar brand name, logo, and/or imagery as an existing commercial non-cannabis counterpart (CNCC). We assessed each package for similarities with its CNCC with respect to brand name, product name, font, color, flavors, and brand/promotional characters. We examined cannabis content indicators including: THC content per package and serving, cannabis leaf symbol, product warnings, cannabis terms, cannabis motifs, activation time, and guidance on edible use.

RESULTS

We collected photos of 731 cannabis products; 267 (36%) were edibles of which 22 (8%) represented 13 unique copycat/lookalike products. Eight used exact brand/product names as existing CNCCs, and five used similar names. Packages copied or imitated a mean of 3.9 of six features and indicated cannabis content with a mean of 4.1 of eight features. Thirteen packages indicated a mean THC content of 459 mg/package. Four reported THC dose per serving, with a mean dose of 47.5 mg.

CONCLUSIONS

Our content analysis highlights three key concerns. First, copycat/lookalike edibles subtly indicate cannabis content while using high fidelity replication or imitation of their CNCC. Second, THC content is high and there were multiple 10 mg THC doses in the equivalent of 1 serving of a CNCC. Third, these products may be attractive to children.

Changes in cannabis use modes among Canadian youth across recreational cannabis legalization: Data from the COMPASS prospective cohort study

INTRODUCTION

Canadian youth consume cannabis in multiple ways, including by smoking, vaping, and eating or drinking. Existing evidence suggests that these behaviours may change after law liberalization, though data regarding youth are scarce. We investigated changes in cannabis modes of use and associated factors across the federal legalization of recreational cannabis use for adults in Canada, among a large sample of underage youth before alternative products were made legally available.

METHODS

Data were available from 2953 longitudinally linked Canadian high school students who reported on their cannabis use during the 2017/2018 and 2018/2019 school years. We explored whether students maintained a single or multiple cannabis use mode(s), contracted, or expanded the number of modes used. We then used generalized estimating equations to analyse associations of baseline characteristics with use mode trajectory.

RESULTS

Expansion of cannabis use modes (42.3%) was more common than maintenance of a single mode (31.3%), maintenance of multiple modes (14.3%), or reduction (12.1%). Students who maintained multiple modes were significantly more likely to have high amounts of weekly spending money (AOR 1.68), to binge drink (AOR 2.25) or vape (AOR 1.99), to use cannabis regularly (AOR 2.67), and to endorse more symptoms of depression (AOR 1.06). School support for quitting tobacco, drug, or alcohol use appeared to have no effect.

CONCLUSIONS

Multi-modal cannabis use increased among Canadian youth in our sample. Its association with other substance use and depressive symptoms may indicate clustering of additional harms. Screening for this use pattern may assist in identifying high-risk substance use and should be considered in the design of harm reduction programming.

Demographic and substance use-related differences among high school adolescents who vape cannabis versus use other cannabis modalities

BACKGROUND

Vaping is the second most common modality of using cannabis following smoking. We examined differences in demographics and substance use behaviors between adolescent cannabis vapers and those exclusively using other cannabis modalities.

METHODS

In 2019, 4875 students from six Connecticut high schools completed school-wide, online surveys. Past-month cannabis users (n = 931; 52.8% female, 16.38(1.27) years old, 44.9% non-Hispanic White) reported on cannabis modalities used (e.g., combustible, vaporizable, edible) and were classified as cannabis vapers or non-vapers. Cannabis vapers reported on device type used to vape cannabis: a cannabis-specific device or modified/hacked e-cigarette. Unadjusted and adjusted relationships were examined to identify demographic and substance-related differences between cannabis vapers and non-vapers.

RESULTS

56.3% of past-month cannabis users reported vaping cannabis. Cannabis vapers reported using both cannabis-specific vaporizers (91.9%) and modifying/hacking e-cigarettes (23.7%). Cannabis vapers, relative to other cannabis users, were more likely to be male, White, initiate cannabis use at a younger age; endorse past-month use of all cannabis modalities, alcohol, and e-cigarettes; and report smoking and dabbing cannabis more frequently; consuming more drinks per drinking day; and using e-cigarettes at a younger age and more frequently.

CONCLUSIONS

Relative to other cannabis modalities, vaping was associated with increased use of several cannabis products and other substances. Adolescent past-month cannabis users reported modifying e-cigarettes to vape cannabis. Findings suggest that regulations should be implemented to prevent e-cigarettes from being modifiable for use with cannabis and highlight the importance of assessing different cannabis use modalities, as vaping was associated with distinct substance-related risks.

Heterogeneities in administration methods among cannabis users by use purpose and state legalization status: findings from a nationally representative survey in the United States, 2020

BACKGROUND AND AIMS

Different cannabis administration methods have differential impacts on health. This study aimed to describe administration methods among cannabis users in the United States categorized by (1) use purpose and (2) state legalization status.

DESIGN

Cross-sectional, probability-based online survey in 2020.

SETTING

All 50 states and Washington DC in the United States.

PARTICIPANTS

A total of 21 903 adults (18+) were recruited from a probability-based online panel to provide nationally representative estimates.

METHODS

Eleven administration methods were grouped into combustion, vaporization, ingestion and topicals. Weighted prevalence was reported among (1) medical-only, recreational-only and dual-purpose users based on self-reported purposes and (2) users in states that legalized both recreational and medical cannabis (RCL states), legalized medical cannabis only and did not legalize cannabis.

FINDINGS

Among past-year users, the proportions of medical-only, recreational-only and dual-purpose users were 25.55, 43.81 and 30.64%, respectively. The most common primary methods were combustion (42.08%) and topicals (28.65%) for medical purposes and combustion (72.07%) and ingestion (15.05%) for recreational purposes. Dual-purpose users were more likely to report combustion and vaporization but less likely to report ingestion and topicals as primary methods for medical use than medical-only users (P < 0.001) and more likely to report combustion and topicals but less likely to report ingestion as primary methods for recreational use than recreational-only users (P < 0.041). A higher proportion of dual-purpose users (82.82%) used more than one method than medical-only (40.52%) and recreational-only users (63.91%) (P < 0.001). For both medical and recreational purposes, RCL states had the lowest rate of combustion and the highest rates of ingestion and topicals reported as primary methods (P < 0.033). The rate of using more than one administration method did not differ across states (P > 0.05).

CONCLUSION

Cannabis users whose purposes are medical, recreational or both tend to differ in their selected administration methods.

Past 30-Day Marijuana Vaping: Prevalence and Predictors of Use in a Nationally Representative Study of U.S. Youth

INTRODUCTION

Vaping has become an increasingly common mode of administration for marijuana among youth, but there are limited data on its prevalence. There is a need to better understand youth prevalence of past 30-day marijuana vaping and its predictors.

METHODS

Data were from a nationally representative sample of students from the Monitoring the Future survey in 2018 (N=9,131). This study examined past 30-day prevalence of marijuana vaping, and for a subset with complete data (n=5,755), the predictors of marijuana vaping among respondents asked about that behavior. Bivariate chi-square tests and multivariable logistic regression estimated the extent to which various factors were associated with marijuana vaping. These factors included the current use of various substances, school-related risk behaviors, attitude and risk behaviors related to substance use, and selected sociodemographic variables.

RESULTS

Past 30-day prevalence of marijuana vaping was higher among 10th graders, male youth, and those in the Other race/ethnicity category. Students who engaged in current past 30-day alcohol use, cigarette use, binge drinking, and nonmedical use of prescription drugs had significantly greater odds of past 30-day marijuana vaping. Past 30-day use was more common among students with a lower perceived risk of marijuana use, those who claimed that it was easy to obtain a vaporizer or marijuana, students with a lower grade point average, and those with recent truancy.

CONCLUSIONS

Past 30-day marijuana vaping is prevalent among U.S. students, and there are robust associations between use and school- and substance-related risk behaviors. These results suggest that the emergence of vaping products might redefine populations at risk, which should be taken into account by marijuana regulatory policies or prevention programs.

Validation of secondary data sources for enumerating marijuana dispensaries in a state commercializing marijuana

OBJECTIVES

To assess 1) the validity of online crowdsourcing platforms in enumerating licensed brick-and-mortar marijuana dispensaries and 2) the validity of state licensing directory and online crowdsourcing platforms in enumerating active brick-and-mortar marijuana dispensaries in California.

METHODS

We obtained business lists from California Bureau of Cannabis Control (BCC) licensing directory and three online crowdsourcing platforms (Weedmaps, Leafly, and Yelp) in May 2019. Calls were made to verify street address, operation status, dispensary category (recreational-only, medical-only, recreational & medical), and presence of storefronts in May-July 2019. Validity measures, including sensitivity, specificity, positive predictive value, and negative predictive value, were calculated when applicable.

RESULTS

In identifying licensed dispensaries in BCC, Leafly had the highest sensitivity (.66) and Yelp had the highest specificity (.87). The dispensary category posted on online crowdsourcing platforms in over 25 % licensed dispensaries and the dispensary category claimed in call verification in over 10 % licensed dispensaries disagreed with the approved category in BCC. There were 2121 businesses combined from BCC and online crowdsourcing platforms, among which 826 were verified to be active brick-and-mortar dispensaries. Weedmaps had the highest sensitivity (.80) and Yelp had the highest negative predictive value (.74) in identifying verified dispensaries. Weedmaps overall had the highest sensitivity in all three dispensary categories. Weedmaps had the highest sensitivity in more populated counties whereas BCC had the highest sensitivity in less populated counties.

CONCLUSIONS

Each secondary data source has strengths and limitations. The findings inform surveillance and research regarding how to best strategize data use when resources are limited.

Changes in Prevalence of Marijuana Consumption Modes Among Colorado High School Students From 2015 to 2017

This study examines data from the Health Kids Colorado Survey to assess changes in modes of marijuana consumption among high school students in Colorado from 2015 to 2017.