Effects of Recreational Marijuana Legalization on College Students: A Longitudinal Study of Attitudes, Intentions, and Use Behaviors

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.

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.

Perceived Risks and Therapeutic Benefits of Cannabis Among College Students Amidst the COVID-19 Pandemic

More than half of the United States has legalized medicinal and/or recreational cannabis. The purpose of the study is to understand cannabis use and perceptions among college students with cannabis experience - 21 years and older - in a legalized cannabis state. Participants included 170 college students, the majority identified as female (72.9%, n = 124) and Latinx/Hispanic (55.9%, n = 95). The online survey included demographic questions and questionnaires measuring cannabis consumption, cannabis use disorder, and quality of life. Participants answered open-ended questions about the negative, positive, and spiritual impact/s of cannabis on their life and health, and how the COVID-19 pandemic impacted their cannabis use. A paired-sample t-test indicated participants significantly found more relief using cannabis compared to non-cannabis treatments or medications. There was no significant correlation between quality of life and cannabis use disorder symptoms. Inductive content analysis of 112 written responses revealed perceived negative effects (e.g., anxiety/mental health issues) and positive effects (e.g., relaxation/stress reduction) from using cannabis. Most participants reported no spiritual benefits; however, some participants discussed cannabis use improving connection to self and self-awareness. Regarding the impact of the COVID-19 pandemic on use, most participants (27.8%) reported increased cannabis use, while some reported decreased cannabis use. These findings reflect the importance of understanding the wide-range of benefits and risks perceived by college students who consume cannabis and how these results can inform the development of university prevention and wellness strategies within states that have legalized recreational and medical cannabis.

Changes in Mental Health Symptoms as a Predictor of Cannabis Coping Motives and Consequences: Examining the Impact of COVID-19 Among College Students

Objective

Cannabis use is common among college students and many students use cannabis to cope with negative affect. The COVID-19 pandemic was a particularly stressful time for college students. Subsequently, the present study compared college students who reported increases in anxiety/depression symptoms since COVID-19 stay at home orders to those who reported no change in anxiety/depression symptoms on cannabis coping motives, use frequency, and negative consequences. Specifically, we examined whether self-reported changes (i.e., group that indicated increases) in poor mental health during COVID-19 were associated with problematic cannabis use via higher cannabis coping motives.

Method

College students (analytic n = 291) completed an online survey for research credit regarding their personal mental health, COVID-19 stressors, and cannabis use behaviors.

Results

Individuals who reported increased depressive symptoms (57.4% of the current sample) due to COVID-19 (as compared to individuals whose depressive symptoms remained the same) reported significantly higher cannabis coping motives (d = .79) as well as more cannabis consequences (d = .37). Further, students who reported increased (61.5% of the current sample) anxiety symptoms (as compared to those whose anxiety symptoms stayed the same) also reported significantly higher cannabis coping motives (d = .47). Moreover, we found that students who reported an increase in depressive/anxiety symptoms reported more cannabis consequences via higher endorsement of cannabis coping motives while controlling for gender, cannabis use frequency, and past-week anxiety/depressive symptoms.

Discussion

Providing resources for substance-free coping strategies to manage the mental health impact of COVID-19 may be extremely useful for this population.

Effect of Technology and Digital Media Use on Adolescent Health and Development: Protocol for a Multimethod Longitudinal Study

BACKGROUND

Technology and digital media (TDM) use is integral to modern adolescence; adolescents have been labeled as "digital natives," since they have had exposure to digital technology for their entire lives. Previous evidence has illustrated TDM's connections with adolescent risk behaviors such as increased alcohol use and social media exposure, as well as relationships with adolescent well-being such as improved socioemotional health and social media connections with peers. Although several recent review articles have described both the benefits and risks of technology use, most individual studies adopt a singular risk-centered approach. In addition, reviews suggest that little evidence exists on the potential mediating and moderating factors between TDM use and well-being and health outcomes, which limits our understanding of what influences the outcomes of interest. Therefore, there is an urgent need to fill these gaps.

OBJECTIVE

This protocol addresses the need to understand how TDM exposure and use affect multiple developmental domains and health outcomes. We address the fragmented nature of previous research, the common focus on single behaviors or conditions, and the typical narrow lens on risks. Our approach further aligns with reviews that called for studies identifying and investigating the factors that moderate the relationships between social media and health behaviors and outcomes.

METHODS

We will address our objective by longitudinally examining over a 2-year period a common set of adolescent participants (N=400, aged 13-15 years) across 3 studies that adopt a multimethodological approach. Study 1 will use TDM to understand the mechanisms behind adolescent health and risk behaviors. Study 2 will use functional magnetic resonance imaging to understand how positive and negative TDM experiences relate to mental and behavioral health in a subsample of 150 adolescents. Study 3 will use a mixed methods design to evaluate self- and other-generated TDM content as the predictors of socioemotional well-being in sexual and gender minority and non-sexual and gender minority adolescents.

RESULTS

Recruitment is ongoing, and the initial results from the first wave of recruitment are expected in 2024.

CONCLUSIONS

This integrated approach to longitudinal data collection from a shared adolescent participant pool will lead to novel analyses and findings, allowing for the examination of the health and well-being risks and benefits associated with TDM use and factors that moderate these relationships. The findings from this study will advance conceptual models and inform new interventions to improve adolescent health.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/50984.

The Impact of Recreational Cannabis Legalization on Cannabis Use and Associated Outcomes: A Systematic Review

Background

Recreational cannabis legalization has become more prevalent over the past decade, increasing the need to understand its impact on downstream health-related outcomes. Although prior reviews have broadly summarized research on cannabis liberalization policies (including decriminalization and medical legalization), directed efforts are needed to synthesize the more recent research that focuses on recreational cannabis legalization specifically. Thus, the current review summarizes existing studies using longitudinal designs to evaluate impacts of recreational cannabis legalization on cannabis use and related outcomes.

Method

A comprehensive bibliographic search strategy revealed 61 studies published from 2016 to 2022 that met criteria for inclusion. The studies were predominantly from the United States (66.2%) and primarily utilized self-report data (for cannabis use and attitudes) or administrative data (for health-related, driving, and crime outcomes).

Results

Five main categories of outcomes were identified through the review: cannabis and other substance use, attitudes toward cannabis, health-care utilization, driving-related outcomes, and crime-related outcomes. The extant literature revealed mixed findings, including some evidence of negative consequences of legalization (such as increased young adult use, cannabis-related healthcare visits, and impaired driving) and some evidence for minimal impacts (such as little change in adolescent cannabis use rates, substance use rates, and mixed evidence for changes in cannabis-related attitudes).

Conclusions

Overall, the existing literature reveals a number of negative consequences of legalization, although the findings are mixed and generally do not suggest large magnitude short-term impacts. The review highlights the need for more systematic investigation, particularly across a greater diversity of geographic regions.

Trends in cannabis use intention around the period of cannabis legalisation in Australia: An age-period-cohort model

INTRODUCTION

This study examines age, time period and birth cohort trends in cannabis use intention and weekly use in Australia over a period in which medicinal cannabis was legalised.

METHODS

Hierarchical age-period-cohort models were used to analyse the National Drug Strategy Household Survey between 2001 and 2019, including 158,395 participants aged 18-79 years.

RESULTS

The hierarchical age-period-cohort model demonstrated a decrease in likelihood of intending to try cannabis as age increases. Similar age effects were found in intending to use cannabis as often or less often. There was broad-based shift in attitudes for people wanting to try cannabis (2007: b = -0.51 [-0.82, -0.21]; 2019: b = 0.68 [0.38, 0.98]) or use cannabis more often (2007: b = -0.15 [-0.50, 0.20]; 2019: b = 0.83 [0.49, 1.18]). The population trend of weekly cannabis use decreased in the earlier periods but increased since 2013 (b = -0.13 [-0.25, -0.02] vs 2019: b = 0.06 [-0.09, 0.20]). This suggests that legalisation would increase uptake of cannabis and consumption among current consumers. There were distinctive inter-generation variations: people born between 1950s and 1960s had more liberal views towards cannabis use than people born before or after (p < 0.05). There were indications that young people born in the 1990 s are catching up with the baby boomers in using cannabis more often if it was legal.

DISCUSSION AND CONCLUSIONS

There has been a population-based shift in Australia in favourable attitudes towards cannabis use, more so among those born in the 1950s to 1960s than other generations. Liberal attitudes and more frequent cannabis use may put certain cohorts at higher risks of cannabis dependence and related harms.

Recreational cannabis legalization and transitions in cannabis use: findings from a nationally representative longitudinal cohort in the United States

AIMS

This study estimated the likelihoods of individuals transitioning to different cannabis use status following recreational cannabis legalization (RCL) in the United States.

DESIGN

Secondary analysis of a nationally representative longitudinal cohort in the United States. We used propensity score matching to balance individual characteristics between RCL and comparison states and generalized mixed regressions to estimate behavioral transitions in matched samples.

PARTICIPANTS

A longitudinal cohort of 21 863 individuals (6925 youths and 14 938 adults) participating in the Population Assessment of Tobacco and Health waves 3 and 4.

SETTING

Four RCL states that implemented RCL between waves 3 and 4 (California, Massachusetts, Nevada and Maine) and comparison states in the United States.

MEASUREMENTS

Transitions in cannabis use over the two waves: (1) from non-users to users; (2) from non-users to weekly users; (3) from users to non-users. Individuals in RCL states were compared with matched individuals in (1) states with medical cannabis legalization (MCL), (2) states not legalizing cannabis (non-legalizing) and (3) MCL and non-legalizing states combined.

FINDINGS

Among youths, the association between RCL and greater odds of transition from non-users to users was seen in comparison with non-legalizing states [odds ratio (OR) = 2.18, 95% confidence interval (CI) = 1.37-3.45] and combined states (OR = 1.73, 95% CI = 1.23-2.42). Evidence was lacking regarding the associations between RCL and transitions from non-users to weekly users and from users to non-users. Among adults, RCL was associated with greater odds of transitions from non-users to users and non-users to weekly users if RCL states were compared with non-legalizing states (OR = 1.68, 95% CI = 1.15-2.46; OR = 1.82, 95% CI = 1.00-3.31, respectively) or combined states (OR = 1.51, 95% CI = 1.11-2.07; OR = 2.09, 95% CI = 1.19-3.66, respectively). RCL was also associated with lower odds of transition from users to non-users if RCL states were compared with non-legalizing states (OR = 0.54, 95% CI = 0.35-0.81).

CONCLUSIONS

There appears to be some evidence that recreational cannabis legalization in the United States is associated with elevated odds of transition to cannabis use among both youths and adults.

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.

Public Health Implications of Cannabis Legalization: An Exploration of Adolescent Use and Evidence-Based Interventions

This article examines the relaxation of state marijuana laws, changes in adolescent use of marijuana, and implications for drug education. Under federal law, use of marijuana remains illegal. In spite of this federal legislation, as of 1 June 2021, 36 states, four territories and the District of Columbia have enacted medical marijuana laws. There are 17 states, two territories and the District of Columbia that have also passed recreational marijuana laws. One of the concerns regarding the enactment of legislation that has increased access to marijuana is the possibility of increased adolescent use of marijuana. While there are documented benefits of marijuana use for certain medical conditions, we know that marijuana use by young people can interfere with brain development, so increased marijuana use by adolescents raises legitimate health concerns. A review of results from national survey data, including CDC’s YRBS, Monitoring the Future, and the National Household Survey on Drug Use, allows us to document changes in marijuana use over time. Increased legal access to marijuana also has implications for educational programming. A “Reefer Madness” type educational approach no longer works (if it ever did). We explore various strategies, including prevention programs for education about marijuana, and make recommendations for health educators.

Identifying risk profiles for marijuana vaping among U.S. young adults by recreational marijuana legalization status: A machine learning approach

INTRODUCTION

This study attempted to identify risk profiles of marijuana vaping by state-level recreational marijuana legalization (RML) status among U.S. young adults (YA).

METHODS

Data were drawn from the most recent two waves of restricted use files of the Population Assessment of Tobacco and Health Study with state identifiers. We analyzed 6155 young adult (18-24 years) respondents who were naïve to marijuana vaping at Wave 4 and had matched data at Wave 5. We employed a two-stage machine learning approach to predict marijuana vaping initiation at Wave 5 with predictors measured at Wave 4.

RESULTS

Among YA who had never vaped marijuana at Wave 4, 19% of those who lived in the states with RML and 15% of those who lived in the states without RML reported marijuana vaping at Wave 5. Substance-use-related predictors were rarely found as leading predictors in the states with RML. In the states without RML, substance use behaviors, including electronic nicotine delivery systems and smokeless tobacco use, and the presence of externalizing symptoms emerged as predictors for marijuana vaping. Results also revealed that nonlinear interactions between the predictors of marijuana vaping.

CONCLUSIONS

Our results highlight the importance of accounting for the RML status in developing risk profiles of marijuana vaping. Externalizing symptoms may be a behavioral endophenotype of marijuana vaping in the states without RML. Machine learning appears to be a promising analytical approach to identify complex interactions between factors in predicting an emerging risk behavior such as marijuana vaping.

Cannabis use among Norwegian university students: Gender differences, legalization support and use intentions, risk perceptions, and use disorder

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Past year cannabis use was fairly common in a sample of Norwegian college students.

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About 6% of users possibly met criteria for use disorder, function of use frequency.

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Legalization attitudes and risk perceptions were associated with cannabis use risk.

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Intentions to use cannabis if legal were evident even among some current non-users.

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Many non-users expressed uncertainty in legalization attitudes and risk perceptions.

Aims

We explored past-year cannabis use and associated characteristics, focusing on legalization attitudes, use intentions, risk perceptions, and possible dependence among Norwegian university/college students.

Methods

We examined a nation-wide sample of Norwegian university/college students (N = 49,688; 67% female) who participated in the Students’ Health and Wellbeing Study (SHoT-study) in 2018. Participants reported past-year substance use, support for cannabis legalization, intent to use cannabis if legal, and perceived risks of weekly use. Past-year cannabis use (including use frequency) was examined in relation to these indicators. Legalization support, use intentions, and risk perceptions were examined in relation to use and gender. Potential cannabis use disorder was assessed with the Cannabis Abuse Screening Test (CAST) and examined in relation to use frequency and gender.

Findings

Past-year use was reported by 15.3% (11.8% women; 22.9% men). Majority of current users (roughly 90%) used no more than 50 times past year, and 6% (3.8% women; 8.5% men) met CAST use disorder criteria. Legalization support, use intentions, and no/low risk perceptions were significantly associated with greater odds of use, and greater use frequency among current users in both crude and adjusted models. Legalization support (23.0%), use intentions (14.0%), and perceptions of no/low risk (29.2%) were also relatively common even among current non-users, especially men. Male gender and more frequent use were associated with greater CAST scores and greater odds of use disorder.

Conclusions

Cannabis use was relatively common in this student sample. In addition to targeting frequent use, interventions may focus on cannabis-related attitudes and risk perceptions among uncertain/uninformed students.