Association of Marijuana Legalization With Marijuana Use Among US High School Students, 1993-2019

Recreational Cannabis Legalization, Retail Sales, and Adolescent Substance Use Through 2021

This cross-sectional study using survey datasets evaluates recreational cannabis legalization and retail sales policies and adolescent substance use through 2021.

Investigating Cannabis-Use Among Students Attending High Schools Within the Cherokee Nation Reservation 2017 and 2019

Oklahoma's medical cannabis is some of the least restrictive in the US. Previous research suggests that American Indian/Alaska Native (AIAN) have higher rates of cannabis use than other racial or ethnic groups. The goals of this paper are, first, to look at cannabis use among high school students living on the Cherokee Nation Reservation before (2017) and after (2019) medical cannabis because legal in Oklahoma (2018) utilizing the Cherokee Nation Youth Risk Behavior Survey (CNYRBS). Second, to describe the socio-demographic characteristics of youth using cannabis in the Cherokee Nation Reservation. Data were retrieved from the 2017 and 2019 CNYRBS. The data for this study included 1,216 high school students who completed the 2017 and 1,476 who completed the 2019 CNYRBS. After removal of incomplete records, there were 2,602 students whose data was analyzed in this study. Data were weighted to be representative of public-school students attending grades 9-12 within Cherokee Nation Reservation. Despite the legalization of medical cannabis in Oklahoma in 2018, there was no change in cannabis use among youth between 2017 and 2019. There were variations in cannabis use based on demographic factors and other substance uses. AIAN individuals had higher odds of current cannabis use compared to non-Hispanic White students, but there were no differences based on ethnicity. Additionally, the use of cigarettes, e-cigarettes, alcohol, and illegal drugs were associated with increased odds of cannabis use among both current and former users compared to those who had never used it. There was no spike in use among youth at least immediately after the legalization of cannabis in the Cherokee Nation Reservation. There were socio-demographic as well as substance use disparities in the use of cannabis.

Systematic Review and Meta-Analysis: Medical and Recreational Cannabis Legalization and Cannabis Use Among Youth in the United States

OBJECTIVE

Dramatic changes in state-level cannabis laws (CL) over the past 25 years have shifted societal beliefs throughout the United States, with unknown implications for youth. In the present study, we conducted an updated systematic review and meta-analysis examining estimated effects of medical cannabis legalization (MCL) and recreational cannabis legalization (RCL) on past-month cannabis use among US youth.

METHOD

A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, followed by a subsequent meta-analysis investigating the associations between state-level cannabis laws (ie, MCL vs non-MCL, and RCL vs non-RCL) and past-month cannabis use prevalence among US adolescents and young adults. Supplemental analyses examined age-group effects and design-related factors.

RESULTS

Our search identified 4,604 citations, 34 and 30 of which were included in qualitative and quantitative analyses, respectively. Meta-analysis of MCL studies identified no significant association between MCL and change in past-month youth cannabis use (odds ratio [OR] = 0.981, 95% CI = 0.960, 1.003). Meta-analysis of RCL studies showed significantly increased odds of past-month cannabis use (OR = 1.134, 95% CI = 1.116-1.153). Meta-analysis of more recent studies, however, showed a significantly increased odds of past-month cannabis use among both adolescents and young adults (OR = 1.089, 95% CI = 1.015,1.169, and OR = 1.221, 95% CI = 1.188,1.255, respectively).

CONCLUSION

Cannabis legalization has complex and heterogenous effects on youth use that may differ across law types. Our meta-analytic results showed modest positive effects of RCL on past-month cannabis use (more so in young adults than in adolescents) and minimal effects of MCL on these outcomes in US youth. Given the shift toward recreational legalization, additional focus on RCL effects is warranted.

A systematic review of evidence on integrated management of psychiatric disorders in youth who use cannabis

Given the risks to mental health associated with cannabis use in youth and the increase in cannabis legalization worldwide and in the U.S., there is a need to understand existing evidence-based approaches to integrated management of psychiatric disorders in youth who use cannabis. This systematic review aimed to appraise the current evidence on integrated treatment for adolescents and young adults with common psychiatric disorders who engage in regular cannabis use. A total of 989 studies were screened for inclusion. Study's titles and abstracts were screened and advanced to full text review for further screening by two independent reviewers. Thirty-five full-text articles were reviewed, with five articles ultimately meeting all criteria for inclusion. Five randomized controlled trials examined the effects of therapeutic interventions in youth with common psychiatric disorders who used cannabis, including two studies on depression, one on bipolar disorder, one on anxiety and one on PTSD were reviewed. No studies were considered high in risk of bias. Overall, there is a paucity of research on the treatment of comorbid adolescent mental health disorders and cannabis use, which limits the ability to draw evidence-based treatment recommendations.

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.

Perceptions, Attitudes, and Knowledge of Cannabis and its Use: A Qualitative Study among Herbal Heart Study Young Adult Cannabis Consumers in South Florida

Growing cannabis use among young adults in the United States surpasses research and public understanding, raising health concerns despite potential benefits. Limited research focuses on their knowledge, attitudes, risks, and motivations, especially in states with limited legalization. This study explores cannabis knowledge and attitudes among healthy young adult cannabis consumers to understand their risk and benefit perceptions. Data include a subsample of participants in the Herbal Heart Study, a cohort to examine subclinical cardiovascular risk among healthy young adult (18-35 years old) cannabis consumers and non-consumers. A qualitative thematic analysis of the interviews was performed using a deductive approach driven by the theory of the Health Belief Model to generate categories and codes. Dedoose was used to organize transcripts and coding. A total of 22 young adult cannabis consumers (M age = 25.3, SD = 4.4) were interviewed between May 5, 2021- September 23, 2022. Participants were predominantly female (n = 13) and Hispanic (n = 9) or non-Hispanic Black (n = 7). Five themes were identified: perceived health benefits and risks associated with cannabis use, motivation for cannabis use, knowledge of cannabis, and perceived barriers to cannabis use. Participants discussed knowledge, positive/negative attitudes toward cannabis, and perceived risks/benefits based on personal experience and gathered information. Some showed knowledge deficits, and most wanted more health-related cannabis research. Given the current climate of rising cannabis legalization, availability of novel cannabis products, and societal acceptance, further research and evidence-based cannabis literacy for young adults are essential to keep pace with liberalization trends.

Associations between Adolescent Marijuana Use, Driving after Marijuana Use and Recreational Retail Sale in Colorado, USA

OBJECTIVE

We investigated associations between the retail distribution of recreational marijuana in Colorado and (i) past 30-day marijuana use and (ii) driving after marijuana use (DAMU) among a representative sample of public high school students using four waves of data from a state surveillance system.

METHODS

Past 30-day marijuana use was assessed among all sampled students (n = 85,336). DAMU was assessed among students 15 years or older who indicated driving (n = 47,518). Modified Poisson regression with robust variance estimates was used to estimate prevalence ratios (PR) comparing the pre-distribution (2013) and post-distribution (2015, 2017, 2019) periods for marijuana-related behaviors. Frequency of behavioral engagement was assessed using a multinomial approach.

RESULTS

An estimated 20.3% of students engaged in past 30-day marijuana use and 10.5% of student drivers engaged in DAMU. Retail distribution of recreational marijuana was not significantly associated with the prevalence of any marijuana use or DAMU. However, it was associated with 1.16 (95% CI: 1.04-1.29) times the prevalence of using marijuana one or two times in the last 30 days, 1.27 (1.03, 1.55) times the prevalence of DAMU one time, and 0.82 (0.69, 0.98) times the prevalence of DAMU six or more times. No significant associations were observed for the remaining frequency categories.

CONCLUSIONS

Approximately 1 in 10 students who drive reported DAMU. Varying prevalence in the frequency of past 30-day marijuana use and DAMU was observed following the retail distribution of recreational marijuana in Colorado. Care should be taken to properly educate adolescent drivers regarding the dangers of DAMU.

Impact of Cannabis Legalization on Adolescent Cannabis Use

Because of substantial limitations in available national data, such as inconsistencies among surveys and small sample sizes, the increased prevalence of cannabis use among adolescents since recreational legalization has not been directly observed. Nevertheless, both usage frequency and product potency have significantly increased, alongside alternative routes of delivery to smoking, such as vaping cannabis. Moreover, certain populations may be especially vulnerable to the effects of legalization. Regardless of differing state-level cannabis legalization status, the adverse consequences of cannabis on youth have clear negative impacts on mental health, medical symptoms, educational outcomes, and increased risk of addiction to other substances.

The highs and the lows: Recreational marijuana laws and mental health treatment

Recreational marijuana laws (RMLs) continue to grow in popularity, but the effects on mental health treatment are unclear. This paper uses an event-study within a difference-in-differences framework to study the short-run impact of state RMLs on admissions into mental health treatment facilities. The results indicate that shortly after a state adopts an RML, they experience a decrease in the average number of mental health treatment admissions. The findings are driven by white, Black, and Medicaid-funded admissions and are consistent for both male and female admissions. The results are robust to alternative specifications and sensitivity analysis.

Assessing the Impact of Recreational Cannabis Legalization on Cannabis Use Disorder and Admissions to Treatment in the United States

Purpose of Review

Policy implications from changes in recreational cannabis laws (RCLs) have raised public health concerns. While numerous studies have examined the impact of RCLs on cannabis use, there is less research on the risk of developing cannabis use disorder (CUD). This review summarizes the latest research on the effects of RCLs on CUD prevalence and cannabis treatment admissions.

Recent Findings

Nine studies were published between 2016 - 2022 that examined RCLs and CUD or treatment. Findings generally indicate an increase in CUD prevalence associated with legalization, but effects differ by age group. There was no significant association between legalization and CUD treatment admissions, and CUD admissions decreased overall during the study periods.

Summary

To improve policy, prevention, and treatment services, policymakers should monitor RCLs' effects on adverse public health outcomes and researchers should consider the effects on individual and community-level characteristics. We discuss methodological challenges in conducting state-level research and provide suggestions for future studies.

Awareness and use of tobacco products among underage individuals: findings from the altria client services underage tobacco use survey 2020-2022

BACKGROUND

Tobacco use among underage individuals is a public health concern. Timely data about tobacco products, especially emerging products such as novel oral nicotine products (NPs), can provide critical information for the prevention of underage tobacco use. With a recent federal law raising the legal age of purchase of tobacco products from 18 to 21, it is of interest to benchmark awareness and use of tobacco products in the new underage population, young adults 18-20 years old. This study provides estimates on awareness and use of tobacco products among underage individuals 13-20 years old during May 2020 to August 2022 in the United States.

METHODS

Altria Client Services Underage Tobacco Use Survey (UTUS) is a repeated cross-sectional survey conducted every quarter-year. A stratified random sampling approach was used to draw nationally representative samples of household dwelling individuals 13-20 years old. Information about the awareness and use of tobacco products was obtained via online self-administration or phone interviews after a consent/assent process.

RESULTS

A sizable portion of underage individuals were aware of NPs (~ 40% among youth and ~ 50% among underage young adults), although past 30-day use was low (< 2%). The lowest levels of awareness and use were observed for heated tobacco products and snus. E-cigarettes were the most used tobacco products among underage individuals. Underage young adults (i.e., 18-20 year olds) were more likely to use tobacco products than youth (i.e., 13-17 year olds). There was no substantial change over time in the awareness and use of tobacco products during the study period despite a slight increase in past 30-day prevalence of e-cigarette use among youth between quarter 1 of 2021 and quarter 2 of 2022.

CONCLUSIONS

The awareness and use of tobacco products remained relatively stable between May 2020 and August 2022. There is a notable level of awareness of novel NPs among underage individuals.

Have recreational marijuana laws undermined public health progress on adult tobacco use?

Public health experts caution that legalization of recreational marijuana may normalize smoking and undermine the decades-long achievements of tobacco control policy. However, very little is known about the impact of recreational marijuana laws (RMLs) on adult tobacco use. Using newly available data from the Population Assessment of Tobacco and Health (PATH) and dynamic difference-in-differences and discrete-time hazard approaches, we find that RML adoption increases prior-month marijuana use among adults ages 18-and-older by 2-percentage-points, driven by an increase in marijuana initiation among prior non-users. However, this increase in adult marijuana use does not extend to tobacco use. Rather, we find that RML adoption is associated with a lagged reduction in electronic nicotine delivery systems (ENDS) use, consistent with the hypothesis that ENDS and marijuana are substitutes. Moreover, auxiliary analyses from the National Survey on Drug Use and Health (NSDUH) show that RML adoption is associated with a reduction in adult cigarette smoking. We conclude that RMLs may generate tobacco-related health benefits.

Effects of cannabis legalization on the use of cannabis and other substances

PURPOSE OF REVIEW

As more jurisdictions legalize cannabis for non-medical use, the evidence on how legalization policies affect cannabis use and the use of other substances remains inconclusive and contradictory. This review aims to summarize recent research findings on the impact of recreational cannabis legalization (RCL) on cannabis and other substance use among different population groups, such as youth and adults.

RECENT FINDINGS

Recent literature reports mixed findings regarding changes in the prevalence of cannabis use after the adoption of RCL. Most studies found no significant association between RCL and changes in cannabis use among youth in European countries, Uruguay, the US, and Canada. However, some studies have reported increases in cannabis use among youth and adults in the US and Canada, although these increases seem to predate RCL. Additionally, there has been a marked increase in unintentional pediatric ingestion of cannabis edibles postlegalization, and an association between RCL and increased alcohol, vaping, and e-cigarette use among adolescents and young adults.

SUMMARY

Overall, the effects of cannabis legalization on cannabis use appear to be mixed. Further monitoring and evaluation research is needed to provide longer-term evidence and a more comprehensive understanding of the effects of RCL.

Recreational marijuana laws and the misuse of prescription opioids: Evidence from National Survey on Drug Use and Health microdata

Several studies have concluded that legalizing medical marijuana can reduce deaths from opioid overdoses. Drawing on micro data from the National Survey on Drug Use and Health, a survey uniquely suited to assessing patterns of substance use, we examine the relationship between recreational marijuana laws (RMLs) and the misuse of prescription opioids. Using a standard difference-in-differences (DD) regression model, we find that RML adoption reduces the likelihood of frequently misusing prescription opioids such as OxyContin, Percocet, and Vicodin. However, using a two-stage procedure designed to account for staggered treatment and dynamic effects, the DD estimate of relationship between RML adoption and the likelihood of frequently misusing prescription opioids becomes positive. Although event study estimates suggest that RML adoption leads to a decrease in the frequency of prescription opioid abuse, this effect appears to dissipate after only 2 or 3 years.

Long-Term Impact of Medical Marijuana Laws on the Burden of Cannabis Use Disorders in US Male and Female Adolescents and Young Adults

Deregulation of cannabis use has raised concerns regarding its potential effects on health, particularly in adolescents and young adults. Here, we extracted data from the Global Burden of Disease database to estimate the long-term effect (> 5 years) of medical marijuana laws (MML) on 2019 cannabis use disorders Disability Adjusted Life Years (2019 CUD DALYs) in US male and female adolescents (15-19 years old) and young adults (20-24 years old). Socio-cultural, demographic and economic characteristics were used as baseline covariates. To improve the robustness of estimation, we took advantage of machine learning techniques. We found no significant effect of MML on 2019 CUD DALYS in each of our four age/sex groups. Estimates from a marginal structural model taking into account age and sex strata in the same model were also non-significant. Our findings suggest that MML may have a negligible effect (if any) on cannabis use disorders in this population group.

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.

Impact of Cannabis Legalization on Adolescent Cannabis Use

Because of substantial limitations in available national data, such as inconsistencies among surveys and small sample sizes, the increased prevalence of cannabis use among adolescents since recreational legalization has not been directly observed. Nevertheless, both usage frequency and product potency have significantly increased, alongside alternative routes of delivery to smoking, such as vaping cannabis. Moreover, certain populations may be especially vulnerable to the effects of legalization. Regardless of differing state-level cannabis legalization status, the adverse consequences of cannabis on youth have clear negative impacts on mental health, medical symptoms, educational outcomes, and increased risk of addiction to other substances.

Edible marijuana products and potential risks for pediatric populations

PURPOSE OF REVIEW

In recent years, an increasing number of states have legalized marijuana, also known as cannabis, for recreational use. As marijuana becomes more accessible, adolescent use and accidental pediatric exposures are likely to become broad public health concerns. Edible marijuana products, which are consumable foods or beverages that contain cannabis extract, are particularly enticing to youth, as they come in appealing forms such as candies, cookies, and drinks. The purpose of this review is to provide pediatricians with an overview of the different types and potential dangers associated with edible marijuana products.

RECENT FINDINGS

Edible marijuana products are often indistinguishable in appearance from normal food items and lack the smell and visible smoke associated with inhaled marijuana. Because they are inconspicuous, palatable, and easily accessible, they are increasingly popular among adolescents. Additionally, the packaging of edible baked goods, candies, and drinks is often purposefully very similar to that of mainstream foods, increasing the risk of accidental ingestion by children. An edible marijuana product must be digested before Δ9-tetrahydrocannabinol can enter the bloodstream, so there is a delayed onset of effects when consuming edibles compared with inhaling marijuana. This also predisposes users to accidental overconsumption.

SUMMARY

Greater knowledge of edible marijuana product consumption by pediatric populations will allow pediatricians to more effectively help patients and advise caregivers in cases of overconsumption, dependence, or accidental ingestion. It is important for parents, guardians, and educators to be able to successfully identify edible marijuana products and recognize signs of cannabis use.

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.

Motives, Frequency, and Consequences of Cannabis Use Among College Students

We investigated profiles of cannabis use motives among current cannabis-consuming college students. Then we assessed profile differences in demographic characteristics, social contexts of use, regulatory environment, alcohol use, negative affect, negative consequences, and cannabis use. Participants ( N = 1, 213) were from three universities in states with different cannabis legislation. Six profiles emerged: Low Motives, Low to Moderate Enhance, High Enhance, High Enhance & Social + Moderate Expand, High Enhance & Cope, and High Motives. Profiles differed in social contexts of use, sex, alcohol use, negative affect, and regulatory environment. Profiles endorsing high and multiple motives had higher cannabis use and negative consequences, relative to profiles with low or fewer motives. Profiles characterized by high avoidance motives (i.e., coping) had the highest cannabis use and consequences. Interventions targeting types and intensity of motives for cannabis-use may help reduce use and related consequences among college students who use cannabis.