The effect of medical marijuana laws on adolescent and adult use of marijuana, alcohol, and other substances

Clinician perspectives on adolescent cannabis-related beliefs and behaviors following recreational cannabis legalization

BACKGROUND

As more states legalize cannabis, studies are needed to understand the potential impacts of recreational cannabis legalization (RCL) on adolescents from the perspective of clinicians who care for them.

METHODS

This qualitative study characterized clinician perspectives on whether cannabis legalization is associated with changes in adolescents' cannabis use beliefs, behaviors, and consequences. Semi-structured qualitative interviews were conducted with 32 clinicians in a large healthcare organization from 9/6/2022-12/21/2022. Video-recorded interviews were transcribed and analyzed using thematic analysis.

RESULTS

The 32 participants (56.3 % female, mean [SD] age, 45.9 [7.6] years; 65.3 % non-Hispanic White) were from Addiction Medicine (n = 13), Psychiatry/Mental Health (n = 7), Pediatrics (n = 5), and the Emergency Department (n = 7). Clinicians described post-RCL increases in adolescent cannabis use, use of non-combustible modes and high-potency products, and younger age of first use. Clinicians reported social, physical, and policy changes, including changes in social norms, appealing advertisements, marketing, and easier access. Many noted fewer perceived harms among adolescents and greater self-medication post-RCL. They described how RCL contributed to increased parental cannabis use and permissiveness around adolescent use. Finally, many described post-RCL increases in cannabis hyperemesis syndrome, and several noted increased cannabis-related psychosis and acute intoxication, and decreased court-mandated treatment.

CONCLUSIONS

Clinicians from diverse specialties described post-RCL increases in adolescent cannabis use and cannabis-related consequences, alongside changes in social norms, access, marketing and advertisements, and decreased perceptions of harms. Findings can inform strategies to support adolescents in the context of increased cannabis availability and acceptability post-legalization and support the development of hypotheses for broader-scale quantitative work.

High times and troubled relationships: Recreational marijuana laws and intimate partner violence

This study explores the relationship between Recreational Marijuana Laws (RMLs) and intimate partner violence (IPV). While marijuana is often considered harmless, the existing medical literature reveals both positive and negative impacts of its active ingredient on brain function. Utilizing a difference-in-difference methodology spanning 2006-2016 across 39 states, we find that RMLs produce a 20 percent increase in IPV incidents per 100,000 individuals, which appears to be mediated through mental health issues and binge drinking. These findings highlight the likely need for preventive and proactive policies to address the complex interplay of marijuana, RMLs, and IPV.

Uneven effects of twenty years of Chile's cannabis policy implementation in cannabis onset

BACKGROUND

In Chile, Laws 19366 and 20000, implemented in 1995 and 2005 respectively, regulated and sanctioned cannabis' personal use, cultivation and trafficking.

METHODS

We use thirteen biannual cross-sectional national surveys data from 1994 to 2018 to examine the effect of Laws 19366 and 20000-using the rate of individuals incarcerated per 100000 population due to drug-related crimes as proxy-on the age of onset of cannabis use over time. We estimate the effect of these policies using a mixed proportional hazards framework that models the transition to first cannabis use in 47,832 individuals aged 12-21.

RESULTS

Overall, changes in these laws did not affect the transition to first cannabis use. However, increases in the rate of individuals incarcerated were associated with decreases on the age of onset of cannabis use in females and individuals living in affluent neighborhoods or in specific regions.

CONCLUSION

We find no evidence of cannabis policy changes affecting the age of onset of cannabis use across all individuals aged 12-21. Policy effects associated with decreases in cannabis onset age in females and individuals from affluent neighborhoods or specific regions can be explained by using theoretical frames that recognize specific dynamics of cannabis supply and demand.

Medical marijuana laws and mental health in the United States

The consequences of legal access to medical marijuana for individuals' well-being are controversially assessed. We contribute to the discussion by evaluating the impact of the introduction of medical marijuana laws across US states on self-reported mental health considering different motives for cannabis consumption. Our analysis is based on BRFSS survey data from close to eight million respondents between 1993 and 2018 that we combine with information from the NSDUH to estimate individual consumption propensities. We find that eased access to marijuana through medical marijuana laws reduce the reported number of days with poor mental health for individuals with a high propensity to consume marijuana for medical purposes and for those individuals who likely suffer from frequent pain.

Associations between cannabis policies and state-level specialty cannabis use disorder treatment in the United States, 2004-2019

BACKGROUND

Cannabis use disorder (CUD) treatment prevalence decreased in the US between 2002 and 2019, yet structural mechanisms for this decrease are poorly understood. We tested associations between cannabis laws becoming effective and self-reported CUD treatment.

METHODS

Restricted-use 2004-2019 National Surveys on Drug Use and Health included people ages 12+ classified as needing CUD treatment (i.e., past-year DSM-5-proxy CUD or last/current specialty treatment for cannabis). Time-varying indicators of medical cannabis laws (MCL) with/without cannabis dispensary provisions differentiated state-years before/after laws using effective dates. Multi-level logistic regressions with random state intercepts estimated individual- and state-adjusted CUD treatment odds by MCLs and model-based changes in specialty CUD treatment state-level prevalence. Secondary analyses tested associations between CUD treatment and MCL or recreational cannabis laws (RCL).

RESULTS

Using a broad treatment need sample definition in 2004-2014, specialty CUD treatment prevalence decreased by 1.35 (95 % CI = -2.51, -0.18) points after MCL without dispensaries and by 2.15 points (95 % CI = -3.29, -1.00) after MCL with dispensaries provisions became effective, compared to before MCL. Among people with CUD in 2004-2014, specialty treatment decreased only in MCL states with dispensary provisions (aPD = -0.91, 95 % CI = -1.68, -0.13). MCL were not associated with CUD treatment use in 2015-2019. RCL were associated with lower CUD treatment among people classified as needing CUD treatment, but not among people with past-year CUD.

CONCLUSIONS

Policy-related reductions in specialty CUD treatment were concentrated in states with cannabis dispensary provisions in 2004-2014, but not 2015-2019, and partly driven by reductions among people without past-year CUD. Other mechanisms (e.g., CUD symptom identification, criminal-legal referrals) could contribute to decreasing treatment trends.

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.

Experiencing violence and other predictors of within-person same-day use of multiple substances in youth: a longitudinal study in emergency settings

Background: Although experiencing violence is a risk factor for substance use among youth, its association with same-day use of multiple substances (a form of polysubstance use) and mitigating factors is less well understood.Objectives: To identify whether prosocial factors modified the effect of experiencing violence on the frequency of same-day use, and examine gender-specific risk/protective factors for same-day use.Methods: We analyzed longitudinal data from a cohort of youth who use drugs aged 14-24 (n = 599; 58% male) presenting to an urban emergency department between 2009-2011 and assessed biannually for two years. Using Poisson-generalized linear models with person-level fixed effects, we estimated within-person associations between self-reported experiencing violence and same-day use and analyzed gender and peer/parent support as effect modifiers. We adjusted for negative peer influence, parental drug and alcohol use, family conflict, anxiety and depression, and age.Results: Overall, positive parental support corresponded to lower rates of same-day use (rate ratio [RR]:0.93, 95% CI:0.87-0.99) and experiencing violence was associated with higher rates of same-day use (RR:1.25, 95% CI:1.10-1.41). Violence exposure was a risk factor among males (RR:1.42, 95% CI:1.21-1.66), while negative peer influences and parental substance use were risk factors among females (RR:1.63, 95% CI:1.36-1.97 and RR:1.58, 95% CI:1.35-1.83, respectively). Positive peer support reduced the association between violence exposure and same-day use among males (RR:0.69, 95% CI:0.57-0.84, p < .05).Conclusions: Tailored interventions may address gender differences in coping with experiencing violence - including interventions that promote parental support among males and reduce influence from parental substance use among females.

Positive psychological interventions on alcohol use and consequences: Pilot randomized trial in a young adult cannabis-using sample

INTRODUCTION

Young adults exhibit high rates of concurrent alcohol and cannabis use, which is associated with more negative alcohol-related consequences. Positive psychological interventions have successfully been leveraged to target alcohol, cannabis, and nicotine use, as well as substance use disorders, and may be a useful harm reduction approach to reduce alcohol-related consequences. This pilot study sought to generate effect sizes for two positive psychological interventions, Savoring and Three Good Things, on frequency of alcohol use, quantity of alcohol use, and alcohol-related consequences.

METHODS

The current study used data from a pilot study testing positive psychological interventions to reduce cannabis use and cannabis-related consequences in young adults (ages 18 to 25) who used cannabis at least once per week within the prior month (N = 50, Mage = 22.72, 72 % men, 40 % White). Participants reported baseline alcohol and cannabis use and alcohol-related consequences, then the study randomized them to complete a daily Savoring intervention, Three Good Things, or a control exercise, and completed daily text message surveys for two weeks (i.e., the intervention period) and a follow-up survey.

RESULTS

Analyses revealed no significant differences across experimental conditions on alcohol use frequency, alcohol use quantity, or alcohol-related consequences at baseline or follow-up. Paired samples t-tests demonstrated that participants in the Savoring group showed large, significant decreases in alcohol-related consequences (t[16] = 2.28, p = .04, gav = 0.54); no decreases occurred in frequency or quantity of alcohol use. The Three Good Things group showed no significant decreases in alcohol-related consequences, frequency of alcohol use, or quantity of alcohol use.

CONCLUSIONS

Results suggest that a larger scale clinical trial is warranted to determine whether Savoring and Three Good Things might function as harm reduction interventions to reduce alcohol-related consequences in young adults who concurrently use alcohol and cannabis. Future research should use a larger sample, a longer intervention administration period, and a longer follow-up period to examine these positive psychological interventions more rigorously.

Unhealthy behaviors associated with mental health disorders: a systematic comparative review of diet quality, sedentary behavior, and cannabis and tobacco use

Background

There are well-established literatures documenting the associations between mental disorders and unhealthy behaviors such as poor diet quality, sedentary behavior, and cannabis and tobacco use. Few studies have attempted to understand the respective findings in light of each other, however.

Objective

The purpose of this review was to assemble comparable data for each behavior-disorder association and assess the associations in terms of their overall strength. The review aimed to include a representative, but not exhaustive, range of studies that would allow for explorative comparisons.

Methods

Eligible studies were identified via Pubmed searches and citation searching, restricted to publications no older than 2015 written in English. To obtain comparable data, only studies that reported findings as odds ratios were included, and risk of bias related to study samples, behavioral measurement disparities, and control variables was assessed via sensitivity analyses. Findings for each disorder were compared on the basis of different measures of central tendency.

Results

From 3,682 records, 294 studies were included. The review found evidence of associations between each of the four unhealthy behaviors and psychosis, depression, anxiety, bipolar disorder, attention-deficit/hyperactivity disorder (ADHD), and post-traumatic stress disorder (PTSD), while personality disorder was only investigated in relation to cannabis and tobacco use. In overall comparison, the associations were generally of similar strength, and only the association between cannabis use and personality disorder was exceptional in terms of being significantly stronger than its counterparts across disorders and across behaviors. Analyses of bias risk identified some influence from behavioral measurement disparities and lack of adequate statistical control, but findings were generally robust across a range of sensitivity analyses.

Conclusion

This explorative and comparative review found that poor diet quality, sedentary behavior, and cannabis and tobacco use are about equally strongly associated with a range of different mental disorders. Given the general nature of these associations, we should probably understand them to reflect a general and shared etiology. However, the findings in this review should be regarded as tentative until confirmed by more comprehensive investigations.

The effect of marijuana use in adolescence on college and graduate degree attainment

We estimate the long-term effect of using marijuana in adolescence on college and graduate degree attainment measured approximately 20 years later. We rely on the first two waves (1994-1996) and the fifth wave (2016-2018) of the National Longitudinal Study of Adolescent to Adult Health and estimate instrumental variables models that exploit the network structure at the second degree by using marijuana use status of friends of friends who are not themselves friends of the respondent in order to instrument for the respondent's marijuana use. Our models also include school and grade fixed effects. Marijuana use in adolescence leads to a large reduction in the likelihood of college and graduate degree attainment by the time respondents are aged 33-43 years old.

Association of Cannabis Legalization with Cannabis Positive Drug Screening in US Veterans

Background

Although cannabis legalization is associated with increases in self-report cannabis use, biological measures of cannabis use are needed to address potential bias introduced by improved self-reporting of cannabis use in states enacting medical cannabis laws (MCL) and recreational cannabis laws (RCL).

Objective

Quantify the role of MCL and RCL enactment in cannabis positive urine drug screen (UDS) prevalence among Veterans Health Administration (VHA) emergency department (ED) patients from 2008 to 2019.

Design

Staggered-adoption difference-in-difference analysis were used to estimate the role of MCL and RCL in cannabis positive UDS data, fitting adjusted linear binomial regression models to estimate the association between MCL and RCL enactment and prevalence of cannabis positive UDS.

Participants

VHA enrolled veterans aged 18-75 years with ≥1 ED visit in a given year from 2008 to 2019.

Main Measures

Receipt of ≥1 cannabis positive UDS during an ED visit were analyzed.

Key Results

From 2008 to 2019, adjusted cannabis positive UDS prevalences increased from 16.4% to 25.6% in states with no cannabis law, 16.6% to 27.6% in MCL-only enacting states, and 18.2% to 33.8% in RCL-enacting states. MCL-only and MCL/RCL enactment was associated with a 0.8% (95% CI, 0.4-1.0) and 2.9% (95% CI, 2.5-3.3) absolute increase in cannabis positive UDS, respectively. Significant effect sizes were found for MCL and RCL, such that 7.0% and 18.5% of the total increase in cannabis positive UDS prevalence in MCL-only and RCL states could be attributed to MCLs and RCLs.

Conclusions

In this study of VHA ED patients, MCL and RCL enactment played a significant role in the overall increases in cannabis positive UDS. The increase in a biological measure of cannabis use reduces concerns that previously documented increases in self-reported cannabis use from surveys are due to changes in patient willingness to report use as it becomes more legal.

Cannabis Policy and Consumption: Taking into account Substitution Effects

Background: Previous studies examining the cannabis-alcohol substitution effect have found that medical cannabis policies may result in substituting the use of cannabis in place of alcohol use. Objectives: This study adds to the literature on cannabis-alcohol substitution by analyzing the effect of decriminalization, medicinal cannabis, and adult-use legalization cannabis policies (2002-2019) on cannabis and alcohol use and substance substitution for all 50 states and the District of Columbia (N=867). Results: Results support the notion that liberalized cannabis policies can increase the prevalence of cannabis use. An adult-use legalization specific analysis yielded findings suggesting a complex and heterogenous effect of such laws on cannabis-alcohol complementation. Conclusion: Given the lack of clarity and heterogenous effects of cannabis laws, policy makers should carefully take into consideration the benefits of medical cannabis laws, along with the risks of decriminalization and adult-use legalization.

A Review of the Effects of Adolescent Cannabis Use on Physical Health

The current review highlights the available research related to cannabis and indicators of physical health in a variety of domains. Various studies have found associations between cannabis use with pulmonary, cardiovascular, gastrointestinal, and endocrine function as well as body mass index and sleep. At this time, more research is needed to understand the influence of cannabis use on physical health, particularly among adolescent samples.

The relationship between medical marijuana use and prescription pain reliever use among U.S. adults: A retrospective analysis utilizing the 2015-2019 National Survey on Drug Use and Health (NSDUH)

Background

Despite a number of states in the U.S. enacting medical marijuana policies, there is currently a lack of research outlining the role that individual-level factors play in predicting medical marijuana use, especially regarding use and misuse of prescription pain relievers. The overall aim of this study was to assess the prevalence of medical marijuana use in the U.S. and to identify clinical, social, and demographic predictors.

Methods

A retrospective secondary database analysis was conducted utilizing five years of the National Survey on Drug Use and Health (NSUDH). A multivariable logistic regression model assessed the association between prescription pain reliever use and medical marijuana in the adult U.S. population while adjusting for substance use factors, psychiatric factors, and demographic characteristics.

Results

Within the U.S. adult population from 2015 to 2019, medical marijuana use increased from 1.6% to 2.4%, while appropriate prescription pain reliever use decreased from 33.4% to 27.5%, and prescription pain reliever misuse decreased from 4.7% to 3.7%. Of all marijuana users, 15.1% resided within non-medical marijuana states. Medical marijuana users are more likely to have a serious mental illness (14.0% vs. 4.4%) and a non-marijuana related substance dependence (5.3% vs. 1.2%). Past-year medical marijuana use was significantly more likely to be reported among appropriate users of prescription pain relievers (OR = 1.99, p < .001) and misusers (OR = 1.94, p < .001) (relative to nonusers).

Conclusions

Prescription pain reliever appropriate use and misuse were associated with higher odds of medical marijuana use. This study identified a potential treatment gap among individuals residing in states with no medical marijuana availability. These study findings highlight the potential benefits of medical marijuana legalization that future research can build on to guide policy making decisions.

Effects of Oral Delta-9-Tetrahydrocannabinol in Women During the Follicular Phase of the Menstrual Cycle

Background: This study examined effects of oral delta-9-tetrahydrocannabinol (THC) in women at two phases of the menstrual cycle differing in circulating levels of estrogen (E). Pre-clinical findings indicate that E increases sensitivity to THC and other cannabinoids, raising the possibility that higher E may be a risk factor for adverse responses to THC in women. Methods: We examined subjective and behavioral responses to THC (7.5 and 15 mg oral) and placebo in women during the early follicular (EF) phase when E levels are low and the late follicular (LF) phase when E levels are higher. Outcome measures included self-report ratings of drug effects, cardiovascular measures, and biochemical verification of ovarian hormone levels. We hypothesized that women would exhibit greater responses to THC during the LF phase compared to the EF phase. Results: On most measures, responses to THC were similar during the two phases. However, on two self-report measures, "Wanting More" drug and anxiety, the effects occurred slightly earlier after drug administration in women who were tested during the EF phase. Conclusions: We conclude that the differences in levels of E occurring during the early and LF phase of the menstrual cycle do not strongly influence responses to THC. It remains to be determined whether responses are similarly stable across other cycle phases, or in women receiving exogenous hormone treatments.

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.

Evaluation of the Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Questionnaire and its Relations to Cannabis-Related Problems

Cannabis use and the prevalence of cannabis use disorder (CUD) among emerging adults are on the rise. Several indicators of cannabis use (e.g., quantity, frequency) as they relate to negative outcomes have been posited in the extant literature. Despite research examining links between indicators and cannabis outcomes, few assessments of cannabis use indicators exist. The Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Inventory (DFAQ-CU) was developed to assess cannabis use across a range of factors. However, the factor structure of the DFAQ-CU has not been replicated. Further, the DFAQ-CU was modeled using reflective strategies despite formative strategies being conceptually appropriate. The present study utilized principal components analyses (PCA) and principal axis factoring (PAF) to evaluate the structure of the DFAQ-CU. PCA yielded a four-component solution; PAF resulted in a five-factor solution. Linear regression found significant relations between PCA components and PAF factors with CUD symptoms and cannabis-related problems; however, effect sizes were larger for the PAF suggesting possible misdisattenuation. The PCA components demonstrated evidence of discriminant and convergent validity with measures of cannabis and alcohol behavior. The study informs research and clinical work through the refinement of cannabis use assessment and enhancing our understanding of the importance of model selection.

Chronic pain, cannabis legalisation, and cannabis use disorder among patients in the US Veterans Health Administration system, 2005 to 2019: a repeated, cross-sectional study

BACKGROUND

Cannabis use disorder is associated with considerable comorbidity and impairment in functioning, and prevalence is increasing among adults with chronic pain. We aimed to assess the effect of introduction of medical cannabis laws (MCL) and recreational cannabis laws (RCL) on the increase in cannabis use disorder among patients in the US Veterans Health Administration (VHA).

METHODS

Data from patients with one or more primary care, emergency, or mental health visit to the VHA in 2005-19 were analysed using 15 repeated cross-sectional VHA electronic health record datasets (ie, one dataset per year). Patients in hospice or palliative care were excluded. Patients were stratified as having chronic pain or not using an American Pain Society taxonomy of painful medical conditions. We used staggered-adoption difference-in-difference analyses to estimate the role of MCL and RCL enactment in the increases in prevalence of diagnosed cannabis use disorder and associations with presence of chronic pain, accounting for the year that state laws were enacted. We did this by fitting a linear binomial regression model stratified by pain, with time-varying cannabis law status, fixed effects for state, categorical year, time-varying state-level sociodemographic covariates, and patient covariates (age group [18-34 years, 35-64 years, and 65-75 years], sex, and race and ethnicity).

FINDINGS

Between 2005 and 2019, 3 234 382-4 579 994 patients were included per year. Among patients without pain in 2005, 5·1% were female, mean age was 58·3 (SD 12·6) years, and 75·7%, 15·6%, and 3·6% were White, Black, and Hispanic or Latino, respectively. In 2019, 9·3% were female, mean age was 56·7 (SD 15·2) years, and 68·1%, 18·2%, and 6·5% were White, Black, and Hispanic or Latino, respectively. Among patients with pain in 2005, 7·1% were female, mean age was 57·2 (SD 11·4) years, and 74·0%, 17·8%, and 3·9% were White, Black, and Hispanic or Latino, respectively. In 2019, 12·4% were female, mean age was 57·2 (SD 13·8) years, and 65·3%, 21·9%, and 7·0% were White, Black, and Hispanic or Latino, respectively. Among patients with chronic pain, enacting MCL led to a 0·135% (95% CI 0·118-0·153) absolute increase in cannabis use disorder prevalence, with 8·4% of the total increase in MCL-enacting states attributable to MCL. Enacting RCL led to a 0·188% (0·160-0·217) absolute increase in cannabis use disorder prevalence, with 11·5% of the total increase in RCL-enacting states attributable to RCL. In patients without chronic pain, enacting MCL and RCL led to smaller absolute increases in cannabis use disorder prevalence (MCL: 0·037% [0·027-0·048], 5·7% attributable to MCL; RCL: 0·042% [0·023-0·060], 6·0% attributable to RCL). Overall, associations of MCL and RCL with cannabis use disorder were greater in patients with chronic pain than in patients without chronic pain.

INTERPRETATION

Increasing cannabis use disorder prevalence among patients with chronic pain following state legalisation is a public health concern, especially among older age groups. Given cannabis commercialisation and widespread public beliefs about its efficacy, clinical monitoring of cannabis use and discussion of the risk of cannabis use disorder among patients with chronic pain is warranted.

FUNDING

NIDA grant R01DA048860, New York State Psychiatric Institute, and the VA Centers of Excellence in Substance Addiction Treatment and Education.

Socioeconomic and psychosocial determinants of substance misuse - a national perspective

Accurate estimates of population drug use and an understanding of the factors that influence substance choice are essential for the development of appropriate and targeted prevention strategies and campaigns. This review aims to provide an overview of the socioeconomic and psychosocial factors that influence substance use patterns within the Australian population through exploration of current and historical examples of substance misuse. Australia's comparatively large online drug market is reflective of the country's relative geographic isolation and high local drug prices. Legislation, particularly relating to cannabis cultivation and personal use, has evolved significantly in response to increased scientific and commercial applications and changing attitudes towards medical and personal use. Methylamphetamine use is disproportionately high, attributed to Australia's geographic location, high rates of local manufacture, steady cost, and increased purity. Despite the increased cost of cocaine over time, the profile of users appears to dictate rates of use. The prevalence of injecting drug use is driven by a lack of education, perceived risk, stigma, and other social factors. Additionally, psychosocial factors also contribute to substance misuse among specific population subgroups such as petrol sniffing among Indigenous Australians. Understanding the reasons for geographical variability in illicit drug use assists in the interpretation of substance-associated behavior in specific groups/populations and in guiding future intervention efforts and predictions of emerging trends. In addition, an understanding of factors influencing local drug usage may assist forensic practitioners in evaluating the occurrence and effects of particular substances that may emerge as significant factors in drug-related deaths.

Medical cannabis laws lower individual market health insurance premiums

BACKGROUND

To evaluate the impact of medical cannabis laws (MCLs) on health insurance premiums. We study whether cannabis legalization significantly impacts aggregate health insurer premiums in the individual market. Increases in utilization could have spillover effects to patients in the form of higher health insurance premiums.

METHODS

We use 2010-2021 state-level U.S. private health insurer financial data from the National Association of Insurance Commissioners. We examined changes to individual market health insurance premiums after the implementation of medical cannabis laws. We employed a robust difference-in-differences estimator that accounted for variation in policy timing to exploit temporal and geographic variation in state-level medical cannabis legalization.

RESULTS

Seven years after the implementation of Medical Cannabis laws, we observe lower health insurer premiums in the individual market. Starting seven years post-MCL implementation, we find a reduction of $-1662.7 (95% confidence interval [CI -2650.1, -605.7]) for states which implemented MCLs compared to the control group, a reduction of -$1541.8 (95% confidence interval [CI 2602.1, -481.4]) in year 8, and a reduction of $-1625.8, (95% confidence interval [CI -2694.2, -557.5]) in year 9. Due to the nature of insurance pooling and community rating, these savings are appreciated by cannabis users and non-users alike in states that have implemented MCLs.

CONCLUSIONS

The implementation of MCLs lowers individual-market health insurance premiums. Health insurance spending, including premiums, comprises between 16% and 34% of household budgets in the United States. As healthcare costs continue to rise, our findings suggest that households that obtain their health insurance on the individual (i.e., not employer sponsored) market in states with MCLs appreciate significantly lower premiums.

Recreational cannabis legislation and binge drinking in U.S. adolescents and adults

BACKGROUND

Recreational cannabis laws (RCLs) may have spillover effects on binge drinking. Our aims were to investigate binge drinking time trends and the association between RCLs and changes in binge drinking in the United States (U.S.).

METHODS

We used restricted National Survey on Drug Use and Health data (2008-2019). We examined trends in the prevalence of past-month binge drinking by age groups (12-20, 21-30, 31-40, 41-50, 51+). Then, we compared model-based prevalences of past-month binge drinking before and after RCL by age group, using multi-level logistic regression with state random intercepts, an RCL by age group interaction term, and controlling for state alcohol policies.

RESULTS

Binge drinking declined overall from 2008 to 2019 among people aged 12-20 (17.54% to 11.08%), and those aged 21-30 (43.66% to 40.22%). However, binge drinking increased among people aged 31+ (ages 31-40: 28.11% to 33.34%, ages 41-50: 25.48% to 28.32%, ages 51+: 13.28% to 16.75%). When investigating model-based prevalences after versus before RCL, binge drinking decreased among people aged 12-20 (prevalence difference=-4.8%; adjusted odds ratio (aOR)=0.77, [95% confidence interval (CI) 0.70-0.85]), and increased among participants aged 31-40 (+1.7%; 1.09[1.01-1.26]), 41-50 (+2.5; 1.15[1.05-1.26]) and 51+ (+1.8%; 1.17[1.06-1.30]). No RCL-related changes were noted in respondents ages 21-30.

CONCLUSIONS

Implementation of RCLs was associated with increased past-month binge drinking in adults aged 31+ and decreased past-month binge drinking in those aged < 21. As the cannabis legislative landscape continues to change in the U.S., efforts to minimize harms related to binge drinking are critical.

Chronic Pain, Cannabis Legalization and Cannabis Use Disorder in Veterans Health Administration Patients, 2005 to 2019

Background

The risk for cannabis use disorder (CUD) is elevated among U.S. adults with chronic pain, and CUD rates are disproportionately increasing in this group. Little is known about the role of medical cannabis laws (MCL) and recreational cannabis laws (RCL) in these increases. Among U.S. Veterans Health Administration (VHA) patients, we examined whether MCL and RCL effects on CUD prevalence differed between patients with and without chronic pain.

Methods

Patients with ≥1 primary care, emergency, or mental health visit to the VHA and no hospice/palliative care within a given calendar year, 2005-2019 (yearly n=3,234,382 to 4,579,994) were analyzed using VHA electronic health record (EHR) data. To estimate the role of MCL and RCL enactment in the increases in prevalence of diagnosed CUD and whether this differed between patients with and without chronic pain, staggered-adoption difference-in-difference analyses were used, fitting a linear binomial regression model with fixed effects for state, categorical year, time-varying cannabis law status, state-level sociodemographic covariates, a chronic pain indicator, and patient covariates (age group [18-34, 35-64; 65-75], sex, and race and ethnicity). Pain was categorized using an American Pain Society taxonomy of painful medical conditions.

Outcomes

In patients with chronic pain, enacting MCL led to a 0·14% (95% CI=0·12%-0·15%) absolute increase in CUD prevalence, with 8·4% of the total increase in CUD prevalence in MCL-enacting states attributable to MCL. Enacting RCL led to a 0·19% (95%CI: 0·16%, 0·22%) absolute increase in CUD prevalence, with 11·5% of the total increase in CUD prevalence in RCL-enacting states attributable to RCL. In patients without chronic pain, enacting MCL and RCL led to smaller absolute increases in CUD prevalence (MCL: 0·037% [95%CI: 0·03, 0·05]; RCL: 0·042% [95%CI: 0·02, 0·06]), with 5·7% and 6·0% of the increases in CUD prevalence attributable to MCL and RCL. Overall, MCL and RCL effects were significantly greater in patients with than without chronic pain. By age, MCL and RCL effects were negligible in patients age 18-34 with and without pain. In patients age 35-64 with and without pain, MCL and RCL effects were significant (p<0.001) but small. In patients age 65-75 with pain, absolute increases were 0·10% in MCL-only states and 0·22% in MCL/RCL states, with 9·3% of the increase in CUD prevalence in MCL-only states attributable to MCL, and 19.4% of the increase in RCL states attributable to RCL. In patients age 35-64 and 65-75, MCL and RCL effects were significantly greater in patients with pain.

Interpretation

In patients age 35-75, the role of MCL and RCL in the increasing prevalence of CUD was greater in patients with chronic pain than in those without chronic pain, with particularly pronounced effects in patients with chronic pain age 65-75. Although the VHA offers extensive behavioral and non-opioid pharmaceutical treatments for pain, cannabis may seem a more appealing option given media enthusiasm about cannabis, cannabis commercialization activities, and widespread public beliefs about cannabis efficacy. Cannabis does not have the risk/mortality profile of opioids, but CUD is a clinical condition with considerable impairment and comorbidity. Because cannabis legalization in the U.S. is likely to further increase, increasing CUD prevalence among patients with chronic pain following state legalization is a public health concern. The risk of chronic pain increases as individuals age, and the average age of VHA patients and the U.S. general population is increasing. Therefore, clinical monitoring of cannabis use and discussion of the risk of CUD among patients with chronic pain is warranted, especially among older patients.

Research in Context

Evidence before this study: Only three studies have examined the role of state medical cannabis laws (MCL) and/or recreational cannabis laws (RCL) in the increasing prevalence of cannabis use disorder (CUD) in U.S. adults, finding significant MCL and RCL effects but with modest effect sizes. Effects of MCL and RCL may vary across important subgroups of the population, including individuals with chronic pain. PubMed was searched by DH for publications on U.S. time trends in cannabis legalization, cannabis use disorders (CUD) and pain from database inception until March 15, 2023, without language restrictions. The following search terms were used: (medical cannabis laws) AND (pain) AND (cannabis use disorder); (recreational cannabis laws) AND (pain) AND (cannabis use disorder); (cannabis laws) AND (pain) AND (cannabis use disorder). Only one study was found that had CUD as an outcome, and this study used cross-sectional data from a single year, which cannot be used to determine trends over time. Therefore, evidence has been lacking on whether the role of state medical and recreational cannabis legalization in the increasing US adult prevalence of CUD differed by chronic pain status.Added value of this study: To our knowledge, this is the first study to examine whether the effects of state MCL and RCL on the nationally increasing U.S. rates of adult cannabis use disorder differ by whether individuals experience chronic pain or not. Using electronic medical record data from patients in the Veterans Health Administration (VHA) that included extensive information on medical conditions associated with chronic pain, the study showed that the effects of MCL and RCL on the prevalence of CUD were stronger among individuals with chronic pain age 35-64 and 65-75, an effect that was particularly pronounced in older patients ages 65-75.Implications of all the available evidence: MCL and RCL are likely to influence the prevalence of CUD through commercialization that increases availability and portrays cannabis use as 'normal' and safe, thereby decreasing perception of cannabis risk. In patients with pain, the overall U.S. decline in prescribed opioids may also have contributed to MCL and RCL effects, leading to substitution of cannabis use that expanded the pool of individuals vulnerable to CUD. The VHA offers extensive non-opioid pain programs. However, positive media reports on cannabis, positive online "information" that can sometimes be misleading, and increasing popular beliefs that cannabis is a useful prevention and treatment agent may make cannabis seem preferable to the evidence-based treatments that the VHA offers, and also as an easily accessible option among those not connected to a healthcare system, who may face more barriers than VHA patients in accessing non-opioid pain management. When developing cannabis legislation, unintended consequences should be considered, including increased risk of CUD in large vulnerable subgroups of the population.

The Impact of Cannabis Use on Adolescent Neurodevelopment and Clinical Outcomes Amidst Changing State Policies

Cannabis is the most common illicit substance used by adolescents and the third most common psychoactive substance after alcohol and nicotine. Cannabis use during adolescence interrupts a critical period of brain development and leads to inappropriate activation of the reward pathway. Because the prefrontal cortex, which is responsible for impulse control and other executive functions, is not fully mature until the mid-twenties, the adolescent brain is especially vulnerable to damage from substance use. Although cannabis remains illegal at the federal level, recent changes in state policies have been associated with increased availability of a wide variety of cannabis products. As new products, formulations, and delivery devices that can deliver higher and faster peak doses of tetrahydrocannabinol enter the market, there is an even greater potential for cannabis to have negative clinical impacts on adolescent health. This article reviews the current literature on the impact of cannabis on adolescent health, including the neurobiology of the adolescent brain, potential clinical outcomes in adolescents who use cannabis, and the effects of changing state policies regarding cannabis on the increased availability of unregulated products.

Cannabis Recreational Legalization and Prevalence of Simultaneous Cannabis and Alcohol Use in the United States

BACKGROUND

Simultaneous cannabis/alcohol use, using both substances within a short time interval so that their effects overlap, has a greater risk of potential negative consequences than single-substance use and is more common in younger age. Relationships between recreational cannabis laws (RCLs) and changes in simultaneous cannabis/alcohol use prevalence remain untested.

OBJECTIVE

To examine trends in simultaneous cannabis/alcohol use from 2008 to 2019, and investigate associations between implementation of RCLs (i.e., presence of active legal dispensaries or legal home cultivation) and simultaneous cannabis/alcohol use in the United States (U.S.).

DESIGN

Repeated cross-sectional samples from the 2008-2019 U.S. National Survey on Drug Use and Health (NSDUH).

PARTICIPANTS

Respondents (51% female) aged 12 and older.

INTERVENTIONS

Changes in simultaneous cannabis/alcohol use before and after RCL implementation (controlling for medical cannabis law implementation) were compared in different age groups (12-20, 21-30, 31-40, 41-50, 51+), using adjusted multi-level logistic regression with state random intercepts and an RCL/age group interaction.

MEASUREMENTS

Self-reported simultaneous cannabis/alcohol use.

RESULTS

From 2008 to 2019, the overall prevalence of simultaneous cannabis/alcohol use declined among those aged 12-20 but increased in adults aged 21+. Model-based simultaneous cannabis/alcohol use prevalence increased after RCL implementation among respondents aged 21-30 years (+1.2%; aOR= 1.15 [95%CI = 1.04-1.27]), 31-40 years (+1.0; 1.15 [1.04-1.27]), and 41-50 years (+1.75; 1.63 [1.34-1.98]), but not in individuals aged <21 or 51+ years.

CONCLUSIONS

Implementation of recreational cannabis policies resulted in increased simultaneous use of cannabis and alcohol, supporting the complementarity hypothesis, but only among adults aged 21+. Efforts to minimize harms related to simultaneous cannabis/alcohol use are critical, especially in states with RCLs. Future studies should investigate cultural norms, perceived harm, and motives related to simultaneous use.

Adult use of highly-potent Δ9-THC cannabis concentrate products by U.S. state cannabis legalization status, 2021

BACKGROUND

Compared to plant/flower cannabis products, cannabis concentrates have higher average potency of delta-9-tetrahydrocannabinol (Δ9-THC), which may be associated with greater likelihood of cannabis-related harms. Information on factors associated with use of cannabis concentrates is needed.

METHODS

Respondents were 4,328 adult past-7-day cannabis users from all 50 U.S. states and Washington DC (DC) who participated in an online 2021 survey. Using logistic regression to generate adjusted odds ratios (aOR), we investigated whether participants in states that enacted recreational cannabis laws (RCL, 12 states plus DC [treated as a state], n = 1,236) or medical cannabis laws (MCL-only, 23 states, n = 2,030) by December 31, 2020 were more likely than those in states without cannabis laws (no-CL, 15 states, n = 1,062) to use cannabis concentrate products in the prior 7 days.

RESULTS

Most participants (92.4%) used plant material in the prior 7 days; 57.0% used cannabis concentrates. In RCL, MCL and no-CL states, concentrate use was reported by 61.5%, 56.6%, and 52.5%, respectively. Compared to participants in no-CL states, odds of using cannabis concentrate products were greater among those in RCL states (aOR = 1.47; CI = 1.17-1.84) and MCL-only states (aOR = 1.29; CI = 1.08-1.55). Whether states had legally-authorized dispensaries had little effect on results.

CONCLUSION

Results suggest that individuals in MCL-only and RCL states are more likely to use cannabis concentrate products. Determining mechanisms underlying these results, e.g., commercialization, could provide important information for prevention. Clinicians should be alert to patient use of concentrates, especially in MCL-only and RCL states. Continued monitoring is warranted as additional states legalize cannabis use.

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.

Medicaid reimbursement rates for primary care services and behavioral health outcomes

We study the effects of changing Medicaid reimbursement rates for primary care services on behavioral health outcomes-defined here as mental illness and substance use disorders. Medicaid enrollees are at elevated risk for these, and other, chronic conditions and are likely to have unmet treatment needs. We apply two-way fixed-effects regressions to survey data specifically designed to measure behavioral health outcomes over the period 2010-2016. We find that higher primary care reimbursement rates reduce mental illness and substance use disorders among non-elderly adult Medicaid enrollees, although we interpret findings for substance use disorders with some caution as they may be vulnerable to differential pre-trends. Overall, our findings suggest positive spillovers from a policy designed to target primary care services to behavioral health outcomes.

A comparison of synthetic control approaches for the evaluation of policy interventions using observational data: Evaluating the impact of redesigning urgent and emergency care in Northumberland

OBJECTIVE

To compare the original synthetic control (OSC) method with alternative approaches (Generalized [GSC], Micro [MSC], and Bayesian [BSC] synthetic control methods) and re-evaluate the impact of a significant restructuring of urgent and emergency care in Northeast England, which included the opening of the UK's first purpose-built specialist emergency care hospital.

DATA SOURCES

Simulations and data from Secondary Uses Service data, a single comprehensive repository for patient-level health care data in England.

STUDY DESIGN

Hospital use of individuals exposed and unexposed to the restructuring is compared. We estimate the impact using OSC, MSC, BSC, and GSC applied at the general practice level. We contrast the estimation methods' performance in a Monte Carlo simulation study.

DATA COLLECTION/EXTRACTION METHODS

Hospital activity data from Secondary Uses Service for patients aged over 18 years registered at a general practice in England from April 2011 to March 2019.

PRINCIPAL FINDINGS

None of the methods dominated all simulation scenarios. GSC was generally preferred. In contrast to an earlier evaluation that used OSC, GSC reported a smaller impact of the opening of the hospital on Accident and Emergency (A&E) department (also known as emergency department or casualty) visits and no evidence for any impact on the proportion of A&E patients seen within 4 h.

CONCLUSIONS

The simulation study highlights cases where the considered methods may lead to biased estimates in health policy evaluations. GSC was found to be the most reliable method of those considered. Considering more disaggregated data over a longer time span and applying GSC indicates that the specialist emergency care hospitals in Northumbria had less impact on A&E visits and waiting times than suggested by the original evaluation which applied OSC to more aggregated data.

Development of cannabis use disorder in medical cannabis users: A 9-month follow-up of a randomized clinical trial testing effects of medical cannabis card ownership

Background

Evidence for long-term effectiveness of commercial cannabis products used to treat medical symptoms is inconsistent, despite increasingly widespread use.

Objective

To prospectively evaluate the effects of using cannabis on self-reported symptoms of pain, insomnia, anxiety, depression, and cannabis use disorder (CUD) after 12 months of use.

Methods

This observational cohort study describes outcomes over 9 months following a 12-week randomized, waitlist-controlled trial (RCT: NCT03224468) in which adults (N = 163) who wished to use cannabis to alleviate insomnia, pain, depression, or anxiety symptoms were randomly assigned to obtain a medical marijuana card immediately (immediate card acquisition group) or to delay obtaining a card for 12 weeks delay (delayed card acquisition group). During the 9-month post-randomization period, all participants could use cannabis as they wished and choose their cannabis products, doses, and frequency of use. Insomnia, pain, depression, anxiety, and CUD symptoms were assessed over the 9-month post-randomization period.

Results

After 12 months of using cannabis for medical symptoms, 11.7% of all participants (n = 19), and 17.1% of those using cannabis daily or near-daily (n = 6) developed CUD. Frequency of cannabis use was positively correlated with pain severity and number of CUD symptoms, but not significantly associated with severity of self-reported insomnia, depression, or anxiety symptoms. Depression scores improved throughout the 9 months in all participants, regardless of cannabis use frequency.

Conclusions

Frequency of cannabis use was not associated with improved pain, anxiety, or depression symptoms but was associated with new-onset cannabis use disorder in a significant minority of participants. Daily or near-daily cannabis use appears to have little benefit for these symptoms after 12 months of use.

Marijuana legalization and opioid deaths

Many states have legalized marijuana over the last two decades, initially for medical purposes and more recently for recreational consumption. Despite prior research, it remains unclear how these policies are related to rates of opioid-involved overdose deaths, which have trended rapidly upwards over time. We examine this question in two ways. First, we replicate and extend previous investigations to show that the prior empirical results are frequently fragile to the choice of specifications and time periods, and probably provide an overly optimistic assessment of the effects of marijuana legalization on opioid deaths. Second, we present new estimates suggesting that legal medical marijuana, particularly when available through retail dispensaries, is associated with higher opioid mortality. The results for recreational marijuana, while less reliable, also indicate that retail sales may be correlated with greater death rates relative to the counterfactual of no legal cannabis. A likely mechanism for these effects is the emergence of illicit fentanyl, which has increased the riskiness of even small positive effects of cannabis legalization on the consumption of opioids.

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.

Relationships between sales of legal medical cannabis and alcohol in Canada. Health Policy 2023;128:28-33. [PMID: 36443110 DOI: 10.1016/j.healthpol.2022.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

The extent to which legalizing cannabis use might lead to increased or decreased alcohol use has important implications for public health, economic growth, and government policy. This study analyzed Canada's monthly per capita sales of alcohol and legal medical cannabis using fixed effect panel data linear regressions. The data covered seven Canadian regions from January 2011 to September 2018, and controlled for changing levels of retail activity, alcohol prices, tertiary education, unemployment, and impaired driving penalties. The analysis estimated that each dollar of legal medical cannabis sold was associated with an average alcohol sales decrease of roughly $0.74 to $0.84. This suggests that medical cannabis was an economic substitute for alcohol in Canada, and that the country's 2017-2018 alcohol sales were roughly 1.8% lower than they would have been without legal medical cannabis. The results therefore indirectly imply that reduced alcohol consumption might have partly offset cannabis legalization's health and economic impacts.

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.

The kids aren't alright: The effects of medical marijuana market size on adolescents

We exploit shocks to US federal enforcement policy to assess how legal medical marijuana market size affects youth marijuana use and consequences for youth traffic-related fatalities. Using hand-collected data on state medical marijuana patient rates to develop a novel measure of market size, we find that legal market growth increases youth marijuana use. Likely mechanisms are lower prices and easier access. Youth die more frequently from alcohol-involved car accidents, suggesting complementarities for youths. The consequences of marijuana legalization for youth are not immediate, but depend on how supply-side regulations affect production and prices.

A Review of the Effects of Adolescent Cannabis Use on Physical Health

The current review highlights the available research related to cannabis and indicators of physical health in a variety of domains. Various studies have found associations between cannabis use with pulmonary, cardiovascular, gastrointestinal, and endocrine function as well as body mass index and sleep. At this time, more research is needed to understand the influence of cannabis use on physical health, particularly among adolescent samples.

Comparison of Health Care Providers Attitudes and Beliefs Regarding Medical Marijuana and Cannabidiol in the Management of Pain and Other Symptoms in Cancer Patients

Background: Medical marijuana (MM) and cannabidiol (CBD) have received increasing attention to manage pain and other symptoms even with limited scientific evidence. Objectives: We examined the attitudes and beliefs of health care providers toward MM and CBD compared to standard treatments for cancer-associated pain and various symptoms. Design: Two sets of anonymous surveys (MM and CBD) containing similar items were completed by clinicians of four symptom-focused specialties. Results: A minority of respondents preferred recommending MM (9%) and CBD (13%), respectively, over opioids for cancer pain, while 11% and 22% felt that MM and CBD, respectively, would be useful to combine with opioids to treat cancer pain. Respondents did not favor MM or CBD over common treatment options for nonpain symptoms. Conclusion: MM and CBD were not preferred over current standard treatments for pain and other symptoms. Responses from the four specialties aligned with unique aspects of their clinical practice.

Association of Recreational Cannabis Legalization With Alcohol Use Among Adults in the US, 2010 to 2019

Importance

In the US, cannabis use has nearly doubled during the past decade, in part because states have implemented recreational cannabis laws (RCLs). However, it is unclear how legalization of adult-use cannabis may affect alcohol consumption.

Objective

To estimate the association between implementation of state RCLs and alcohol use among adults in the US.

Design, Settings, and Participants

This was a cross-sectional study of 4.2 million individuals who responded to the Behavioral Risk Factor Surveillance System in 2010 to 2019. A difference-in-differences approach with demographic and policy controls was used to estimate the association between RCLs and alcohol use, overall and by age, sex, race and ethnicity, and educational level. Data analyses were performed from June 2021 to March 2022.

Exposures

States with RCLs, as reported by the RAND-University of Southern California Schaeffer Opioid Policy Tools and Information Center.

Main Outcomes and Measures

Past-month alcohol use, binge drinking, and heavy drinking.

Results

Of 4.2 million respondents (median age group, 50-64 years; 2 476 984 [51.7%] women; 2 978 467 [58.3%] non-Hispanic White individuals) in 2010 through 2019, 321 921 individuals lived in state-years with recreational cannabis laws. Recreational cannabis laws were associated with a 0.9 percentage point (95% CI, 0.1-1.7; P = .02) increase in any alcohol drinking but were not significantly associated with binge or heavy drinking. Increases in any alcohol use were primarily among younger adults (18-24 years) and men, as well as among non-Hispanic White respondents and those without any college education. A 1.4 percentage point increase (95% CI, 0.4-2.3; P = .006) in binge drinking was also observed among men, although this association diminished over time.

Conclusions and Relevance

This cross-sectional study and difference-in-differences analysis found that recreational cannabis laws in the US may be associated with increased alcohol use, primarily among younger adults and men.

Maintained anxiolytic effects of cannabidiol after treatment discontinuation in healthcare workers during the COVID-19 pandemic

Objective: To assess whether the effects of oral administration of 300 mg of Cannabidiol (CBD) for 28 days on mental health are maintained for a period after the medication discontinuation.

Methods: This is a 3-month follow-up observational and clinical trial study. The data were obtained from two studies performed simultaneously by the same team in the same period and region with Brazilian frontline healthcare workers during the COVID-19 pandemic. Scales to assess emotional symptoms were applied weekly, in the first month, and at weeks eight and 12.

Results: The primary outcome was that, compared to the control group, a significant reduction in General Anxiety Disorder-7 Questionnaire (GAD-7) from baseline values was observed in the CBD group on weeks two, four, and eight (Within-Subjects Contrasts, time-group interactions: F_1-125 = 7.67; p = 0.006; η_p² = 0.06; F_1-125 = 6.58; p = 0.01; η_p² = 0.05; F_1-125 = 4.28; p = 0.04; η_p² = 0.03, respectively) after the end of the treatment.

Conclusions: The anxiolytic effects of CBD in frontline health care professionals during the COVID-19 pandemic were maintained up to 1 month after the treatment discontinuation, suggesting a persistent decrease in anxiety in this group in the real world. Future double-blind placebo-controlled clinical trials are needed to confirm the present findings and weigh the benefits of CBD therapy against potential undesired or adverse effects.

Does expanding access to cannabis affect traffic crashes? County-level evidence from recreational marijuana dispensary sales in Colorado

This article examines the effect of recreational cannabis dispensary sales on traffic crashes by employing difference-in-differences model that exploits the variation in the timing of recreational marijuana dispensary entry across counties within Colorado. Using marijuana-related hospital discharge as a measure of marijuana abuse/misuse, the results indicate a sizable rise in marijuana-related hospital discharges after the entry of retail cannabis stores. However, there is a lack of evidence that traffic crash incidents are affected by the entry. The preferred estimate suggests that, at 90% confidence level, a large increase in traffic crashes by more than 5% can be ruled out.

Substance-Specific Risk Factors among Young Adults: Potential Prevention Targets across Cannabis-Permissive Environments

PURPOSE

This study examined levels of substance-specific risk factors such as perception of harm from substance use among young adults in a range of cannabis-permissive environments. The main objective was to inform future preventive interventions aimed at reducing cannabis use in the context of increasingly permissive environments.

METHODS

Data came from the Community Youth Development Study (CYDS) collected in 2016 when participants were about 23 years old (n = 1,722 participants residing in 46 U.S. states). Young adults self-reported their perceptions about the harms related to cannabis, alcohol, and cigarette use; attitudes about and ease of access to cannabis and other substances; and perceived wrongfulness and social acceptability of cannabis, alcohol, and cigarette use and of selling of cannabis and other illegal drugs.

RESULTS

Young adults in more permissive cannabis contexts reported higher levels of all cannabis-specific risk factors (e.g., greater access to and more favorable attitudes about cannabis use), except for perception of harm from regular cannabis use. However, permissiveness of the cannabis environment was not associated with heightened levels of risk factors for other substance use (such as alcohol, cigarettes, and opioids).

CONCLUSIONS

Future preventive interventions for young adults living in more permissive cannabis contexts may need to focus on cannabis-specific risk factors in particular and go beyond considerations of harm from regular use. Future studies should replicate these findings with other samples.

Medical cannabis and automobile accidents: Evidence from auto insurance

While many states have legalized medical cannabis, many unintended consequences remain under-studied. We focus on one potential detriment-the effect of cannabis legalization on automobile safety. We examine this relationship through auto insurance premiums. Employing a modern difference-in-differences framework and zip code-level premium data from 2014 to 2019, we find that premiums declined, on average, by $22 per year following medical cannabis legalization. The effect is more substantial in areas near a dispensary and in areas with a higher prevalence of drunk driving before legalization. We estimate that existing legalization has reduced health expenditures related to auto accidents by almost $820 million per year with the potential for a further $350 million reduction if legalized nationally.

U.S. cannabis laws projected to cost generic and brand pharmaceutical firms billions

Legalization of cannabis by U.S. states is likely increasing the use of cannabis as an alternative to conventional pharmaceutical drugs. We examined how cannabis legalization between 1996 and 2019 affected stock market returns for listed generic and brand pharmaceutical companies and found that returns were 1.5-2% lower at 10 days after legalization. Returns decreased in response to both medical and recreational legalization, for both generic and brand drugmakers. Investors anticipate a single legalization event to reduce drugmaker annual sales by $3B on average.

Do opioid prescriptions lead to fatal car crashes?

Widespread opioid misuse suggests a potential for increased fatal car crashes. However, opioid use may not necessarily lead to additional crashes if drivers respond to opioid prevalence by substituting away from more inebriating intoxicants like alcohol. Combining data on local opioid prescription rates and car crashes from the Fatality Analysis and Reporting System, we use two-way fixed effects models to test the direction of the association between prescribing intensity and crash fatalities between 2007 and 2016. We estimate that a 10 percent increase in the local prescription rate is associated with a 1 percent increase in the number of driver deaths in motor vehicle accidents. The association is robust to several model specifications, and isolated to drivers most affected by the opioid crisis: males and 25 to 34 year-olds.

Case Report: Cannabidiol-Induced Skin Rash: A Case Series and Key Recommendations

Cannabidiol (CBD) is a non-psychotomimetic constituent of the Cannabis plant, with potential therapeutic properties for many physical and neuropsychiatric conditions. Isolated CBD has been suggested to have favorable safety and tolerability. Although CBD-related rash is described, few case reports are well documented in the literature, and usually, CBD was used concomitantly with other medications. Thus, we report four women who presented a skin rash after ongoing CBD use. Other causes of these skin rashes were ruled out after conducting an extensive viral and serological detection panel, and three patients had their lesions biopsied. Two patients were re-exposed to the vehicle (MCT) without developing a new skin rash. Therefore, clinicians must be aware of this potential adverse effect of CBD use.

Cannabis legalization and driving under the influence of cannabis in a national U.S. Sample

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A national survey sampled current cannabis users.

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Users in medical cannabis states were less likely to report driving high.

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Users in recreational states were less likely to report driving high.

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Likelihood of driving high varied by frequency of cannabis use.

The relationship between cannabis legalization and traffic safety remains unclear. Physiological measures of cannabis impairment remain imperfect. This analysis used self-report data to examine the relationship between cannabis legalization and driving under the influence of cannabis (DUIC)1.

Using a cross-sectional national sample (2016–2017) of 1,249 past–30-day cannabis users, we regressed self-reported DUIC (driving within three hours of “getting high”) on cannabis legalization (recreational and medical (recreational), medical only (medical), or no legal cannabis), adjusting for demographics, days of use (past 30 days), days of use*legal status, calibration weights, and geographic clustering.

The risk of DUIC in recreational (risk ratio [RR] = 0.41, 95% confidence interval (CI):0.23–0.72) and medical (RR = 0.39, 95% CI:0.20–0.79) states was lower than in states without legal cannabis, with one exception. Among frequent cannabis users (≥20 days per month), there was a significantly lower risk of DUIC for those living in recreational states (RR = 0.70, 95% CI: 0.49–0.99), but not for those living in medical states (RR = 0.87, 95% CI: 0.60–1.24), compared to users living in states without legal cannabis.

The risk of self-reported DUIC was lower in recreational and medical cannabis states compared to states without legal cannabis. The only exception was for frequent users in medical states, for whom there was no difference in risk compared to frequent users living in states without legal cannabis.

The long-run effects of diagnosis related group payment on hospital lengths of stay in a publicly funded health care system: Evidence from 15 years of micro data

Diagnosis Related Group (DRG) payment systems are a common means of paying for hospital services. They reward greater activity and therefore potentially encourage more rapid treatment. This paper uses 15 years of administrative data to examine the impact of a DRG system introduced in England on hospital lengths of stay. We utilize different econometric models, exploiting within and cross jurisdiction variation, to identify policy effects, finding that the reduction of lengths of stay was greater than previously estimated and grew over time. This constitutes new and important evidence of the ability of financing reform to generate substantial and persistent change in healthcare delivery.

Simultaneous Alcohol/Cannabis Use and Driving Under the Influence in the U.S

INTRODUCTION

Alcohol and cannabis are commonly involved in motor vehicle crashes and fatalities. This study examines whether simultaneous use of alcohol/cannabis is associated with higher odds of reporting driving under the influence of alcohol and cannabis in the U.S.

METHODS

Drivers aged ≥16 years with any past-year alcohol and cannabis use in the 2016-2019 National Survey on Drug Use and Health (N=34,514) reported any past-year driving under the influence of alcohol-only, cannabis-only, both alcohol/cannabis, or not driving under the influence. Survey-weighted associations between simultaneous alcohol/cannabis use and each of the driving under the influence outcomes were computed adjusting for sociodemographics and daily alcohol/cannabis use. Analyses were conducted from November 2020 to September 2021.

RESULTS

In 2016-2019, 42% of drivers with past-year alcohol and cannabis use reported driving under the influence (8% alcohol-only, 20% cannabis-only, 14% alcohol/cannabis). Simultaneous alcohol/cannabis use was associated with 2.88-times higher adjusted odds of driving under the influence of cannabis-only (95% CI=2.59, 3.19) and 3.51-times higher adjusted odds of driving under the influence of both alcohol/cannabis (95% CI=3.05, 4.05), compared to not driving under the influence. Associations with driving under the influence of alcohol-only were unexpectedly in the opposite direction (adjusted conditional odds ratio=0.59, 95% CI=0.45, 0.79).

CONCLUSIONS

Overall, 2 in 5 drivers who used alcohol and cannabis reported driving under the influence of alcohol and/or cannabis. People reporting simultaneous alcohol/cannabis use were more likely to report cannabis-related driving under the influence. Prevention strategies should target individuals reporting simultaneous alcohol/cannabis use to reduce the occurrence of driving under the influence.

Relationships of Cannabis Policy Liberalization With Alcohol Use and Co-Use With Cannabis: A Narrative Review

PURPOSE

The liberalization of cannabis policies has the potential to affect the use of other substances and the harms from using them, particularly alcohol. Although a previous review of this literature found conflicting results regarding the relationship between cannabis policy and alcohol-related outcomes, cannabis policies have continued to evolve rapidly in the years since that review.

SEARCH METHODS

The authors conducted a narrative review of studies published between January 1, 2015, and December 31, 2020, that assessed the effects of cannabis policies on the use of alcohol in the United States or Canada.

SEARCH RESULTS

The initial search identified 3,446 unique monographs. Of these, 23 met all inclusion criteria and were included in the review, and five captured simultaneous or concurrent use of alcohol and cannabis.

DISCUSSION AND CONCLUSIONS

Associations between cannabis policy liberalization and alcohol use, alcohol-related outcomes, and the co-use of alcohol and cannabis were inconclusive, with studies finding positive associations, no associations, and negative associations. Although several studies found that cannabis policy liberalization was associated with decreases in alcohol use measures, these same studies showed no impact of the cannabis policy on cannabis use itself. The lack of a consistent association was robust to subject age, outcome measure (e.g., use, medical utilization, driving), and type of cannabis policy; however, this may be due to the small number of studies for each type of outcome. This paper discusses several notable limitations of the evidence base and offers suggestions for improving consistency and comparability of research going forward, including a stronger classification of cannabis policy, inclusion of measures of the alcohol policy environment, verification of the impact of cannabis policy on cannabis use, and consideration of mediation effects.

Marijuana Policy Bundles in the American States Over Time and Their Impact on the Use of Marijuana and Other Drugs

American states have used different approaches in adoption of cannabis policies and continue to modify those policies after approval. States also differ in how long it takes to implement such policies, and this influences the availability of legal marijuana. Such policy differences and implementation timelines could influence usage of marijuana and other illicit drugs by adolescents, young adults, and older adults. We develop an original coding scheme for marijuana legalization policies by classifying policy bundles characterized by three views of marijuana: as a pharmaceutical; as a permissive drug, or as a state fiscal revenue source. We test the impact of state legal marijuana policy characteristics on age group rates of marijuana use with panel regression models including control variables and fixed effects for 2000-2019. This design moves beyond a dichotomous construct of marijuana legalization and accounts for the dynamic adaptation of policies beyond their initial adoption. States with a higher pharmaceutical score experienced lower marijuana usage rates for adolescents and young adults while states with a permissive approach or fiscal approach experienced higher rates of marijuana use for all age groups. We find no consistent spillover effect of the pharmaceutical or permissive marijuana policy bundles on other illicit drug use for any age group, but fiscal bundles show some association with greater illicit drug use for adults. These more nuanced measures better reflect state policies as implemented and provide more clarity of the policy impact on target populations' marijuana usage.