Association of cannabis potency with mental ill health and addiction: a systematic review

Disproportionate increase in cannabis use among people with serious psychological distress and associations with psychiatric service use in the United States, 2009-2019

BACKGROUND

Cannabis use is on the rise, but it is unclear how use is changing among individuals with serious psychological distress (SPD) compared to the general population as well as what associations this may have with mental health service use.

METHODS

Retrospective cohort study using the National Survey on Drug Use and Health (NSDUH) 2009-19 public use files of 447,228 adults aged ≥ 18 years. Multivariable logistic regression and predictive margin methods were used to estimate linear time trends in any and greater-than-weekly levels of cannabis use by year and SPD status and rates of psychiatric hospitalization and outpatient mental health care.

FINDINGS

Rates of any and weekly-plus cannabis use increased similarly among individuals with SPD compared to those without from 200 to 2014 but more rapidly in SPD every year from 2015 to 2019 (p < 0.001). Among individuals with SPD, no use was associated with a 4.2 % probability of psychiatric hospitalization, significantly less than less-than-weekly (5.0 %, p = 0.037) and weekly-plus cannabis use (5.1 %, p = 0.028). For outpatient mental health care, no use was associated with a 27.4 % probability (95 % CI 26.7-28.1 %) of any outpatient care, significantly less than less than weekly use (32.6 % probability, p < 0.001) and weekly-plus use (29.9 % probability, p = 0.01).

CONCLUSIONS

Cannabis use is increasing more rapidly among individuals with SPD than the general population, and is associated with increased rates of psychiatric hospitalization and outpatient service use. These findings can inform policy makers looking to tailor regulations on advertising for cannabis and develop public health messaging on cannabis use by people with mental illness.

Incident psychotic experiences following self-reported use of high-potency cannabis: Results from a longitudinal cohort study

BACKGROUND AND AIMS

High-potency cannabis has been associated with increased risk of psychosis, but a lack of prospective data hinders understanding of causality in this relationship. This study aimed to combine prospective report of cannabis use with retrospective report of potency to infer the potency of cannabis used in adolescence and explore whether use of cannabis, and the use of high-potency cannabis, in adolescence is associated with incident psychotic experiences.

DESIGN

Population-based birth cohort study.

SETTING

United Kingdom.

PARTICIPANTS

n = 5570 participants who reported on any cannabis use (yes/no) age 16 and 18 years, and n = 1560 participants from this group who also retrospectively reported on cannabis potency.

MEASUREMENTS

In questionnaires at ages 16 and 18, individuals self-reported lifetime cannabis use, and at age 24, participants reported the type of cannabis they most commonly used in the whole time since first using cannabis. Psychotic experiences were assessed at age 24 years using the semi-structured Psychosis-Like Symptom Interview, with incident defined as new-onset occurring between ages 19 and 24 years.

FINDINGS

Use of high-potency cannabis at age 16 or 18 was associated with twice the likelihood of experiencing incident psychotic experiences from age 19-24 (Odds Ratio 2.15, 95% Confidence Intervals 1.13-4.06). There was less evidence for an effect of any cannabis use on incident psychotic experiences (Odds Ratio 1.45, 95% Confidence Intervals 0.94-2.12).

CONCLUSIONS

Use of high-potency cannabis appears to be associated with increased likelihood of psychotic experiences.

Cannabis use disorder and substance use treatment among U.S. adults

INTRODUCTION

Recent expansion of cannabis legalization in multiple states calls for reexamination of the prevalence of cannabis use, cannabis use disorder (CUD), and the associations between CUD severity and substance use treatment. We used Andersen's behavioral model of healthcare use as the conceptual/analytic framework for examining treatment use.

METHODS

We used data from the 2022 National Survey on Drug Use and Health (NSDUH; N = 47,100, age 18+) to describe the prevalence of past-year cannabis use, CUD and CUD severity, other substance use disorders, and substance use treatment. We compared sociodemographic, mental health, healthcare use, and cannabis and other substance use characteristics by CUD severity. Finally, we used logistic regression models to examine the associations between CUD severity and substance use treatment.

RESULTS

Of the U.S. adult population, 23.0 % used cannabis in the past year; 7.0 % had a CUD (3.9 % mild, 1.9 % moderate, and 1.2 % severe CUD); and 4.7 % received substance use treatment. Of past-year cannabis users, 30.3 % had CUD (16.9 % mild, 8.4 % moderate, and 5.0 % severe CUD), and 9.6 % received substance use treatment. Cannabis users had 3-4 times higher rates of other substance use disorders than nonusers. Of those with CUD, 38.4 % had moderate/severe mental illness, 52.4 % had other substance use disorders, and 16.5 % received substance use treatment. Among all cannabis users, moderate (aOR [adjusted odds ratios] = 1.48, 95 % CI = 1.03-2.13) and severe (aOR = 2.57, 95 % CI = 1.60-4.11) CUDs were associated with greater odds of substance use treatment. Among cannabis users without nicotine dependence and alcohol, opioid, tranquilizer/sedative, and stimulant use disorders, only severe CUD (aOR = 6.03, 95 % CI = 3.37-10.78) was associated with greater odds of substance use treatment.

CONCLUSIONS

This study shows increased prevalence of cannabis use and CUD among U.S. adults, and with or without other substance use disorders, CUD was associated with greater odds of substance use treatment. However, the overall low rate of treatment use among those with CUD is concerning. Healthcare providers need to provide education for both medical and recreational users on the development of tolerance and dependence. Harm reduction strategies to minimize the negative consequences of CUD are also needed.

[School-based cannabis prevention: Results of a cluster-randomised trial]

Acluster-randomised trial was conducted in five German federal states to evaluate the results of a school-based cannabis prevention unit. A total of 55 schools were randomly assigned to the intervention group, i.e. participation in a two-hour cannabis prevention workshop conducted by drug prevention specialists in grades 8 and 9, or to a control group with a waiting list. The knowledge, attitudes, intentions and behaviour of the young people in relation to cannabis were measured at the start of the study and six months later. 2,669 pupils(50.8% girls, average age=14.12 years) made up the sample. Effects of the intervention on the students' knowledge (adjusted regression coefficient=0.26 [0.15-0.38], p<0.001) and on the expected negative consequences of cannabis use in adolescents (adjusted regression coefficient=0.15 [0.04-0.25], p=0.006) were found. Both increased significantly more in the intervention group compared to the control group. There were no effects on other attitude-related variables, intentions or behaviour. A very short school-based workshop for grade 8 and 9 students improved their knowledge of and critical attitudes towards cannabis use, but had no effect on their future intentions and cannabis use.

Daily Cannabidiol Administration for 10 Weeks Modulates Hippocampal and Amygdalar Resting-State Functional Connectivity in Cannabis Users: A Functional Magnetic Resonance Imaging Open-Label Clinical Trial

Introduction: Cannabis use is associated with brain functional changes in regions implicated in prominent neuroscientific theories of addiction. Emerging evidence suggests that cannabidiol (CBD) is neuroprotective and may reverse structural brain changes associated with prolonged heavy cannabis use. In this study, we examine how an ∼10-week exposure of CBD in cannabis users affected resting-state functional connectivity in brain regions functionally altered by cannabis use. Materials and Methods: Eighteen people who use cannabis took part in a ∼10 weeks open-label pragmatic trial of self-administered daily 200 mg CBD in capsules. They were not required to change their cannabis exposure patterns. Participants were assessed at baseline and post-CBD exposure with structural magnetic resonance imaging (MRI) and a functional MRI resting-state task (eyes closed). Seed-based connectivity analyses were run to examine changes in the functional connectivity of a priori regions-the hippocampus and the amygdala. We explored if connectivity changes were associated with cannabinoid exposure (i.e., cumulative cannabis dosage over trial, and plasma CBD concentrations and Δ9-tetrahydrocannabinol (THC) plasma metabolites postexposure), and mental health (i.e., severity of anxiety, depression, and positive psychotic symptom scores), accounting for cigarette exposure in the past month, alcohol standard drinks in the past month and cumulative CBD dose during the trial. Results: Functional connectivity significantly decreased pre-to-post the CBD trial between the anterior hippocampus and precentral gyrus, with a strong effect size (d=1.73). Functional connectivity increased between the amygdala and the lingual gyrus pre-to-post the CBD trial, with a strong effect size (d=1.19). There were no correlations with cannabinoids or mental health symptom scores. Discussion: Prolonged CBD exposure may restore/reduce functional connectivity differences reported in cannabis users. These new findings warrant replication in a larger sample, using robust methodologies-double-blind and placebo-controlled-and in the most vulnerable people who use cannabis, including those with more severe forms of Cannabis Use Disorder and experiencing worse mental health outcomes (e.g., psychosis, depression).

Changes in cannabis involvement in emergency department visits for anxiety disorders after cannabis legalization: a repeated cross-sectional study

Background

An increasing number of countries have or are considering legalizing cannabis. One concern is that legalization of cannabis will result in increased cannabis use and in turn a higher prevalence of anxiety disorders. We examined changes in emergency department (ED) visits for anxiety disorders with cannabis involvement in Ontario, over a period that involved medical and non-medical cannabis legalization.

Methods

This repeated cross-sectional population-based study identified all ED visits for anxiety disorders from residents of Ontario, Canada aged 10-105 between 2008 and 2022 (n = 15.7 million individuals). We used interrupted time series analyses to examine immediate and gradual changes in cannabis-involvement and alcohol-involvement (control condition) over four policy periods: medical cannabis legalization (January 2008-November 2015), expanded medical access (December 2015-September 2018), non-medical cannabis legalization with restrictions (October 2018-February 2020), and commercialization which overlapped with the COVID-19 pandemic (March 2020-December 2022). Poisson models were used to generate incidence rate ratios with 95% confidence intervals.

Findings

Over the 14-year study, there were 438,700 individuals with one or more ED visits for anxiety disorders of which 3880 (0.89%) individuals had cannabis involvement and 6329 (1.45%) individuals had alcohol involvement. During the commercialization/COVID-19 period monthly rates of anxiety disorders with cannabis-involvement were 156% higher (0.11 vs 0.29 per 100,000 individuals) relative to the pre-legalization period, compared to a 27% increase for alcohol-involvement (0.27 vs 0.35 per 1100,000 individuals). Rates of anxiety ED visits with cannabis involvement per 100,000 individuals increased gradually over the study period with no immediate or gradual changes after expanded medical access, legalization with restrictions or commercialization/COVID-19. However, during the commercialization/COVID-19 period there were large declines in total anxiety disorder ED visits and anxiety disorder ED visits with alcohol-involvement. Consequently, during this period there was an immediate 31.4% relative increase in the proportion of anxiety visits with cannabis-involvement (incidence rate ratio [IRR], 1.31; 95% CI 1.05-1.65).

Interpretation

We found large relative increases in anxiety disorder ED visits with cannabis involvement over a 14-year period involving medical and non-medical cannabis legalization. These findings may reflect increasing anxiety disorder problems from cannabis use, increasing self-medication of anxiety disorders with cannabis use, or both. The proportion of anxiety ED visits with cannabis involvement increased during the final period of the study but could have been the results of the market commercialization, COVID-19 or both and ongoing monitoring is indicated.

Funding

Canadian Institutes of Health Research (grant #452360).

Association between cannabis potency and mental health in adolescence

INTRODUCTION

In legal and illegal markets, high-potency cannabis (>10 % delta-9-tetrahydrocannabinol (THC)) is increasingly available. In adult samples higher-potency cannabis has been associated with mental health disorder but no studies have considered associations in adolescence.

METHODS

A population-wide study compared no, low and high potency cannabis using adolescents (aged 13-14 years) self-reported symptoms of probable depression, anxiety, and auditory hallucinations.

RESULTS

Of the 6672 participants, high-potency cannabis was used by 2.6 % (n=171) and low-potency by 0.6 % (n=38). After adjustment for sociodemographic factors, tobacco and alcohol use, in comparison to participants who had never used cannabis, people who had used high-potency but not low-potency cannabis were more likely to report symptoms of depression (odds ratio 1.59 [95 % confidence interval 1.06, 2.39), anxiety (OR 1.45, 95 % CI 0.96, 2.20), and auditory hallucinations (OR 1.56, 95 % CI 0.98, 2.47).

CONCLUSIONS

High-potency cannabis use is associated with an increased risk of probable mental health disorders. Services and programming to minimise drug harms may need to be adapted to pay more attention to cannabis potency.

Disentangling the effects of self-control and the use of tobacco and cannabis on violence perpetration from childhood to early adulthood

Associations among self-control, substance use (e.g., tobacco and cannabis use), and violence perpetration have been documented during the adolescent years, but the direction of these associations is not well understood. Using five assessments (covering 9 years) from a prospective-longitudinal study, we examined self-control as a precursor and subsequent mechanism of associations between adolescent substance use and physical violence perpetration. Data came from a large, ethnically diverse sample (n = 1,056). Youth reported their self-control at ages 11, 13, 15, 17, and 20; and their tobacco and cannabis use, and physical violence perpetration at ages 13, 15, 17, and 20. Cross-lagged panel analyses examined associations between these constructs over time. More self-control in late childhood and early adolescence was associated with less future tobacco and cannabis use and physical violence perpetration. Tobacco use was partially associated with more physical violence over time; these associations were not mediated by self-control. Tobacco use in early adolescence was associated with future cannabis use; during late adolescence, tobacco and cannabis use were reciprocally associated over time. Cannabis use was not associated with future physical violence perpetration. Early adolescent self-control plays an important role in later substance use and violence perpetration, and tobacco use has unique links with both later cannabis use and violence perpetration. Supporting the capacities for self-control in late childhood and early adolescence and preventing the initiation and use of entry-level substances could play an important role in preventing both substance use and violence perpetration and their many costs to society.

Harm reduction isn't enough: Introducing the concept of Mindful Consumption and Benefit Maximization (MCBM)

The concept of harm reduction was a radical departure from a century of stigmatizing demand reduction initiatives targeted at people who use drugs. In fact, since the early 1980's Harm Reduction has been used with great success to protect the lives and wellbeing of these individuals. When employed with people who use opioids, the relevancy and importance of harm reduction are easy to grasp because the potential dangers are both quite visible and profound. However, promoting harm reduction practices to people consuming cannabis is a more difficult challenge. Cannabis cannot cause death due to overconsumption, is not associated with the spread of communicable diseases, and is overall a relatively harmless drug both to the individual and society when compared with other legal substances such as tobacco and alcohol. Harm reduction campaigns targeted at cannabis consumers run the risk of sounding overly fearful and stigmatizing, ultimately being ignored like many of the old demand reduction initiatives. Cannabis does have potential harms, and teaching people to mitigate those harms is an important public health goal. This commentary argues that cannabis education targeted at young people should employ mindful consumption and benefit maximization (MCBM) language that promotes harm reduction practices but does not focus on harm as the primary issue related to cannabis use. We define what we mean by mindful consumption and benefit maximization, identify their convergence with harm reduction principles, and argue for their use to both promote knowledge and normalize cannabis consumption that incorporates harm reduction practices.

Young adult retail purchases of cannabis, product category preferences and sales trends in California 2018-21: Differences compared with older adults

AIMS

The aim of this study is to identify cannabis products according to their appeal among young adults and measure product sales trends.

DESIGN, SETTING AND PARTICIPANTS

This was a retrospective comparative study using point-of-sale data from licensed recreational cannabis retailers that include buyer age with birth year entered by retailers, set in California, USA. Cannabis purchases by young adults (aged 21-24, GenZ) were compared with older adults (age 25+) over 4 years (2018-21).

MEASUREMENTS

Sales for six cannabis product categories were analyzed using a commercial data set with imputations and a raw data set. Age-appeal metrics were dollar and unit sales to young adults, and dollar and unit share ratios (young adults/older adults), where a share ratio of 100 denotes age-appeal comparability. A product category was considered more young-adult appealing than others if its mean on a metric was at least one standard deviation above the grand mean across all product categories.

FINDINGS

Flower (cannabis plant material) and vapor pen appealed to young adults based on absolute dollar sales, dominating young-adult spending compared with other cannabis products (37.24 and 31.83%, respectively). Vapor pen and concentrate appealed to young adults based on dollar share ratios of 152, meaning these products comprised a 52% greater share of young-adult cannabis spending relative to older-adult spending (31.83/20.97% and 10.47/6.88%, respectively). Less appealing to young adults were pre-roll, edible/beverage and absorbable products (tincture/sublingual, capsule and topical). Flower showed the largest dollar sales growth (B = +$3.50 million/month), next to vapor pen (B = +$1.55 million/month). Vapor pen tied for highest growth in the percent of product dollars from the largest package size (B = +0.85%/month) and showed the steepest price decline (B = -0.53 price per gram/month).

CONCLUSIONS

In California, USA, from 2018 to 2021, relative to older adults, young adults spent a greater share of their cannabis dollars on vapor pen and concentrate (products with high potency of delta-9-tetrahydrocannabinol).

Exploring causal mechanisms of psychosis risk

Robust epidemiological evidence of risk and protective factors for psychosis is essential to inform preventive interventions. Previous evidence syntheses have classified these risk and protective factors according to their strength of association with psychosis. In this critical review we appraise the distinct and overlapping mechanisms of 25 key environmental risk factors for psychosis, and link these to mechanistic pathways that may contribute to neurochemical alterations hypothesised to underlie psychotic symptoms. We then discuss the implications of our findings for future research, specifically considering interactions between factors, exploring universal and subgroup-specific factors, improving understanding of temporality and risk dynamics, standardising operationalisation and measurement of risk and protective factors, and developing preventive interventions targeting risk and protective factors.

Germany's cannabis act: a catalyst for European drug policy reform?

With the enforcement of the Cannabis Act on 1 April 2024, Germany has adopted one of the most liberal legal approaches to cannabis on the continent. The German model prioritises a non-profit approach and precludes legal market mechanisms. We believe these are the main drivers for increasing cannabis use and related health problems, based on observations following cannabis legalisation in Canada and many states in the U.S. Although legalising cannabis possession and cultivation may not immediately eliminate the illegal market, it is expected to serve public health goals. Despite the overall positive evaluation of the Cannabis Act in Germany, there are three potential areas of concern: the potential for misuse of the medical system, the normalization of cannabis use, and the influence of the cannabis industry. The German model may herald the beginning of a new generation of European cannabis policies, but concerted efforts will be required to ensure that these policy reforms serve rather than undermine public health goals.

Exploring the Significance of Pharmaceutical Care in Mental Health: A Spotlight on Cannabis

Although preliminary evidence suggests Cannabis's efficacy in symptom control for anxiety and depression-psychiatric disorders that significantly impact mental health-much remains to be understood about its effects on the central nervous system (CNS) and how to optimize treatment for these disorders. This study aims to conduct a narrative review to evaluate pharmaceutical care in treating symptoms of anxiety and depression alongside Cannabis use, focusing on safety and therapeutic efficacy optimization. We seek to conceptualize anxiety and depression disorders, review evidence on Cannabis use, evaluate the evidence quality, and identify knowledge gaps. Twelve articles were identified, revealing a significant gap in the literature regarding the integration of pharmaceutical care with Cannabis-based therapies, specifically for anxiety and depression. Despite a growing interest in the relationship between Cannabis and mental health, current research is insufficient for a comprehensive understanding. The relationship between Cannabis use and anxiety and depression disorders requires further, more targeted investigations. This study underscores the importance of future research to fill existing gaps, providing informed insights and robust guidelines for the safe and effective use of Cannabis as part of the treatment for anxiety and depression. It is crucial that pharmaceutical care integrates these therapies responsibly to improve the overall well-being of patients.

Associations of cannabis use, use frequency, and cannabis use disorder with violent behavior among young adults in the United States

BACKGROUND

Most violent crimes (52 %) are committed by adults aged 18-34, who account for 23 % of the US population and have the highest prevalence of cannabis use and cannabis use disorder (CUD). We examined whether and how associations of cannabis use, use frequency, and CUD with violent behavior (i.e., attacking someone with the intent to harm seriously) vary by sex in U.S. young adults.

METHODS

Data were from 113,454 participants aged 18-34 in the 2015-2019 US National Surveys on Drug Use and Health, providing nationally representative data on cannabis use, CUD (using DSM-IV criteria), and violent behavior. Descriptive analyses and bivariate and multivariable logistic regression analyses were conducted.

RESULTS

Among U.S. adults aged 18-34, 28.9 % (95 % CI = 28.5-29.2 %) reported past-year cannabis use (with/without CUD), including 20.5 % (95 % CI = 20.2-20.8 %) with non-daily cannabis without CUD, 4.7 % (95 % CI = 4.5-4.8 %) with daily cannabis use without CUD, 2.1 % (95 % CI = 1.9-2.2 %) with non-daily cannabis use and CUD, and 1.7 % (95 % CI = 1.5-1.8 %) with daily cannabis use and CUD. Past-year adjusted prevalence of violent behavior was higher among males with daily cannabis use but without CUD (2.9 %, 95 % CI = 2.4-2.7 %; adjusted prevalence ratio (PR) = 1.7, 95 % CI = 1.3-2.2) and males with daily cannabis use and CUD (3.1 %, 95 % CI = 2.3-4.0 %; adjusted PR = 1.8, 95 % CI = 1.3-2.4) than males without past-year cannabis use (1.7 %, 95 % CI = 1.6-1.9 %). Adjusted prevalence of violent behavior was higher among females with cannabis use regardless of daily cannabis use/CUD status (adjusted prevalence = 1.6-2.4 %, 95 % CIs = 0.9-3.2 %; adjusted PRs = 1.6-2.4, 95 % CI = 1.3-3.2) than females without past-year cannabis use (1.0 %, 95 % CI = 0.9-1.1 %).

CONCLUSIONS

Research is needed to ascertain the directionality of the associations between cannabis use and violent behavior and underlying sex-specific mechanism(s). Our results point to complex sex-specific relationships between cannabis use frequency, CUD, and violent behavior and highlight the importance of early screening for and treatment of CUD and of preventive interventions addressing cannabis misuse.

The acute effects of cannabis, with and without cannabidiol, on attentional bias to cannabis related cues: a randomised, double-blind, placebo-controlled, cross-over study

RATIONALE

Attentional bias to drug-related stimuli is hypothesised to contribute towards addiction. However, the acute effects of Δ9-tetrahydrocannabinol (THC) on attentional bias to cannabis cues, the differential response in adults and adolescents, and the moderating effect of cannabidiol (CBD) are unknown.

OBJECTIVES

Our study investigated (1) the acute effects of vaporised cannabis on attentional bias to cannabis-related images in adults and adolescents and (2) the moderating influences of age and CBD.

METHODS

We conducted a randomised, double-blind, placebo-controlled, cross-over study where three weight-adjusted vaporised cannabis preparations: 'THC' (8 mg THC for a 75-kg person), 'THC + CBD' (8 mg THC and 24 mg CBD for a 75-kg person) and PLA (matched placebo). Cannabis was administered on 3 separate days to 48 participants, who used cannabis 0.5-3 days/week: 24 adolescents (12 females, aged 16-17) and 24 adults (12 females, aged 26-29). Participants completed a visual probe task with cannabis cues. Our primary outcome was attentional bias to cannabis stimuli, measured using the differential reaction time to a cannabis vs. neutral probe, on 200-ms trials.

RESULTS

In contrast to hypotheses, attention was directed away from cannabis cues on placebo, and there was a main effect of the drug (F(2,92) = 3.865, p = 0.024, η2p = 0.077), indicating THC administration eliminated this bias. There was no significant impact of CBD nor an age-by-drug interaction.

CONCLUSIONS

Acute THC intoxication eliminated attentional bias away from cannabis cues. There was no evidence of differential response in adolescents compared to adults and no evidence that a moderate vaporised dose of CBD altered the impact of cannabis on attentional bias.

TRIAL REGISTRATION

This study was listed with the US National Library of Medicine and registered on ClinicalTrials.gov, URL: Do Adolescents and Adults Differ in Their Acute Response to Cannabis?-Full Text View-ClinicalTrials.gov, registration number: NCT04851392.

Editorial: Adolescent Substance Use Prevention and Treatment Is Our Wheelhouse

In this issue of the Journal, Welsh et al.5 revise and update the National Institute on Drug Abuse (NIDA) "Principles of Adolescent Substance Use Disorder Treatment,"6 and the practice recommendations based on these principles, published by Winters et al. in 2018.7 These principles and recommendations are solidly grounded in current research and reemphasize individualized, voluntary, readily available, comprehensive, and integrated long-term treatment that is not solely focused on detoxification; that addresses biopsychosocial issues and comorbid psychiatric diagnoses; and that is tailored to specific populations. They also recommend addressing misuse without disorder, using annual routine medical visits as opportunities for screening, and engaging families and legal systems to promote treatment adherence. However, the problem of adolescent substance use has been presented with new challenges.

Cannabis use and its association with psychopathological symptoms in a Swiss adult population: a cross-sectional analysis

Background

As the most commonly used illicit substance, cannabis is gaining global acceptance through increasing legalization efforts. This shift intensifies the need for research to guide policymakers and healthcare providers in harm reduction and treatment strategies. Nonetheless, the relationship between psychopathological symptoms and cannabis use remains inadequately understood.

Methods

A sample of regular cannabis consumers completed self-reported assessments for depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), Attention-Deficit/Hyperactivity Disorder (ADHD; Adult ADHD Self-Report Scale V1.1), and psychosis (Early Recognition Inventory based on IRAOS) as well as previous black-market cannabis use patterns. Cannabis Use Disorder Identification Test Revised (CUDIT-R) was used to identify cannabis use disorder (CUD). To understand psychopathological symptom load related to cannabis consumption as well as cannabis use motives, multiple regression models were performed to identify psychopathological variables predicting cannabis use frequency and quantity. Linear regression and correlation analyses were conducted, adjusting for relevant covariates (age, gender, education, alcohol, other substance use).

Results

Three-hundred-sixty regular cannabis users interested in a study on regulated cannabis access in Basel, Switzerland were examined. In bivariate analysis, cannabis use frequency correlated with depressive (r(358) = 0.16, p = 0.003) and anxiety symptom load (r(358) = 0.11, p = 0.034). Cannabis quantity correlated with depressive (r(358) = 0.15, p = 0.005), ADHD (r(358) = 0.14, p = 0.008), and psychosis symptom load (r(358) = 0.16, p = 0.002). However, in the adjusted regression models only depressive and ADHD symptom loads were significantly associated with cannabis use frequency (p = 0.006 and p = 0.034, respectively) and quantity (p = 0.037 and p = 0.019, respectively). No significant correlations between cannabis consumption and anxiety or psychosis remained after adjustment.

Conclusion

ADHD and depressive symptoms correlate with increased cannabis use in a cohort of regular users, suggesting potential self-medication in nonclinical populations. With the rising availability of cannabis worldwide, these results highlight the necessity for longitudinal studies to disentangle the complex dynamics between cannabis consumption and mental health symptoms.

Applying machine learning to international drug monitoring: classifying cannabis resin collected in Europe using cannabinoid concentrations

In Europe, concentrations of ∆9-tetrahydrocannabinol (THC) in cannabis resin (also known as hash) have risen markedly in the past decade, potentially increasing risks of mental health disorders. Current approaches to international drug monitoring cannot distinguish between different types of cannabis resin which may have contrasting health effects due to THC and cannabidiol (CBD) content. Here, we compared concentrations of THC and CBD in different types of cannabis resin collected in Europe (either Moroccan-type, or Dutch-type). We then tested the ability of machine learning algorithms to classify the type of cannabis resin (either Moroccan-type, or Dutch-type) using routinely collected monitoring data on THC and CBD. Finally, we applied the optimal algorithm to new samples collected in countries where the type of cannabis resin was unknown, the UK and Denmark. Results showed that overall, Dutch-type samples had higher THC (Hedges' g = 2.39) and lower CBD (Hedges' g = 0.81) than Moroccan-type samples. A Support Vector Machine algorithm achieved classification accuracy exceeding 95%, with little variation in this estimate, good interpretability, and plausibility. It made contrasting predictions about the type of cannabis resin collected in the UK (94% Moroccan-type; 6% Dutch-type) and Denmark (36% Moroccan-type; 64% Dutch-type). In conclusion, we provide proof-of-concept evidence for the potential of machine learning to inform international drug monitoring. Our findings should not be interpreted as objective confirmatory evidence but suggest that Dutch-type cannabis resin has higher THC concentrations than Moroccan-type cannabis resin, which may contribute to variation in drug markets and health outcomes for people who use cannabis in Europe.

A simple aptamer-dye fluorescence sensor for detecting Δ9-tetrahydrocannabinol and its metabolite in urban sewage

This work developed an aptamer-dye complex as a label-free ratiometric fluorescence sensor for rapid analysis of THC and its metabolite in sewage samples. Integrated with a portable fluorescence capture device, this sensor exhibited excellent sensitivity with visualization of as low as 0.6 μM THC via naked-eye observation, and THC analysis can be accomplished within 4 min, which would be a complementary tool for quantifying THC in sewage samples to estimate cannabis consumption.

Persistent increased severity of cannabis use disorder symptoms in adolescents compared to adults: a one-year longitudinal study

Adolescence is a developmental period characterised by increased vulnerability to cannabis use disorder (CUD). However, previous investigations of this vulnerability have relied on cross-sectional comparisons and lack a detailed assessment of cannabis quantity, a potentially important confounding factor. Here, we aimed to investigate the one-year course of CUD in adolescents compared to adults who currently use cannabis, adjusting for a comprehensive measure of cannabis quantity. Data are from a one-year observational longitudinal study (CannTeen) of adolescents and adults who currently used cannabis regularly with five waves of assessment at 3-monthly intervals, based in London, UK. Participants were n = 70 adults (26-29, 45.7% female), who did not regularly use cannabis when they were under age 18, and n = 76 adolescents (16-17, 50.0% female). The exposure was adolescent (compared to adult) frequent cannabis use. The primary outcome was CUD symptoms measured using the cannabis use disorder identification test revised (CUDIT-R) at five time points. Models were adjusted for cannabis quantity using mean weekly standard THC units (one unit = 5 mg THC). Other covariates included gender, and whether each session occurred before or during the COVID-19 pandemic. In models adjusted for pre-registered covariates, adolescents scored 3.7 points higher on the CUDIT-R compared to the adult group across the 5 assessment waves (3.66 95% CIs 1.99, 5.34). There was also evidence of a linear reduction in symptoms over time in both groups (-0.47, 95%CIs -0.67, -0.27). Adolescents had persistently increased CUD symptoms compared to adults across the 12-month period. This association was robust after adjusting for the quantity of cannabis consumed and other covariates.

The Developmental Trajectory to Cannabis Use Disorder

The increase of cannabis use, particularly with the evolution of high potency products, and of cannabis use disorder (CUD) are a growing healthcare concern. While the harms of adult use and potential medicinal properties of cannabis continue to be debated, it is becoming evident that adolescent cannabis use is a critical window for CUD risk with potential lifelong mental health implications. Herein, we discuss mental health consequences of adolescent cannabis use, factors that contribute to the risk of developing CUD, and what remains unclear in the changing legal landscape of cannabis use. We also discuss the importance of preclinical models to provide translational insight about the causal relationship of cannabis to CUD-related phenotypes and conclude with highlighting opportunities for clinicians and allied professionals to engage in addressing adolescent cannabis use.

AGA Clinical Practice Update on Diagnosis and Management of Cannabinoid Hyperemesis Syndrome: Commentary

DESCRIPTION

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) is to review the available evidence and provide expert advice regarding diagnosis and management of cannabinoid hyperemesis syndrome.

METHODS

This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors.

Effects of Recreational Cannabis Legalization on Mental Health: Scoping Review

OBJECTIVE

Recreational cannabis legalization (RCL) is expanding rapidly. RCL's effects on mental health issues are of particular concern because cannabis use is more frequent among people receiving psychiatric care and is associated with several psychiatric disorders. The authors conducted a scoping review to examine the evidence and discern gaps in the literature concerning the effects of RCL on mental health and to assess the factors responsible for an observed heterogeneity in research results.

METHODS

This scoping literature review followed PRISMA guidelines. Five databases-MEDLINE, CINAHL, Embase, APA PsycInfo, and Web of Science-were searched for English- or French-language reports published between January 1, 2012, and April 30, 2023.

RESULTS

Twenty-eight studies from the United States and Canada were found. The studies were classified by category of the study's data (patients receiving psychiatric care [k=1], death records [k=4], emergency department or hospital records [k=10], and the general population [k=13]) and by the diagnosis (schizophrenia or psychoses, mood disorders, anxiety disorders and symptoms, suicide or suicidal ideation, or other mental health issues) examined. The review findings revealed a paucity of research and indicated mixed and largely inconclusive results of the studies examined. Research gaps were found in the examination of potential changes in cannabis use patterns among people receiving psychiatric care and in the availability of longitudinal studies.

CONCLUSIONS

Clinicians, researchers, and policy makers need to collaborate to address the research gaps and to develop evidence-based policies that reflect a thorough understanding of the effects associated with RCL.

[Effectiveness of a cannabis prevention program in school: results of a randomized prospective study]

BACKGROUND

In the current debate about legalized access to cannabis for adults in Germany, there is widespread agreement about the need for increased prevention among children and young people. The aim of this work is to examine the effectiveness of a school-based cannabis prevention program on knowledge, attitudes, and behavior.

METHOD

Cluster-randomized waiting list control group study with two study arms: "participation in the 'Der grüne Koffer' prevention program", a collection of methods for cannabis prevention, vs. "no participation" and two measurement time points before and four months after the intervention in four German states.

RESULTS

The mean age of the sample of 3976 adolescents from 280 school classes in grades 8 and 9 was 14.02 years (standard deviation = 0.89). The sex ratio was balanced (49.5% female). Cannabis-related knowledge increased significantly more in the intervention group compared to the control group from the first to the second measurement time point (adjusted beta = 0.25 [95% confidence interval: 0.14-0.37]). Attitudes toward cannabis use did not change significantly in either group. In the 8th grades of the intervention group, significantly fewer adolescents (2.9%) started experimenting with cannabis use for the first time during the observation period than in the control group (5.3%), whereas no group difference was detectable in the 9th grades (interaction grade level x group: odds ratio = 2.17 [1.13-4.15], p = 0.019).

DISCUSSION

The evidence of an effect of participation in the "Der grüne Koffer" prevention program on knowledge and first-time use of cannabis in the 8th grade can be considered promising against the background of previous national and international studies, which could not provide evidence of effects of school-based cannabis prevention in middle and late adolescence.

Enhanced cannabis timeline followback (EC-TLFB): Comprehensive assessment of cannabis use including standard THC units and validation through biological measures

AIMS

The aims of this study were to present an enhanced cannabis timeline followback (EC-TLFB) enabling comprehensive assessment of cannabis use measures, including standard tetrahydrocannabinol (THC) units, and to validate these against objectively indexed urinary 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH) concentrations.

DESIGN

We used cross-sectional baseline data from the 'CannTeen' observational longitudinal study.

SETTING

The study was conducted in London, UK.

PARTICIPANTS

A total of 147 participants who used cannabis regularly took part in the study (n = 71 female, n = 76 male; mean age = 21.90, standard deviation = 5.32).

MEASUREMENTS

The EC-TLFB was used to calculate frequency of cannabis use, method of administration, including co-administration with tobacco, amount of cannabis used (measured with unaided self-report and also using pictorial aided self-report) and type of cannabis product (flower, hash) which was used to estimate THC concentration (both from published data on THC concentration of products and analysis of cannabis samples donated by participants in this study). We calculated total weekly standard THC units (i.e. 5 mg THC for all cannabis products and methods of administration) using the EC-TLFB. The outcome variable for validation of past week EC-TLFB assessments was creatinine-normalized carboxy-tetrahydrocannabinol (THC-COOH) in urine.

FINDINGS

All measures of cannabis exposure included in this analysis were positively correlated with levels of THC-COOH in urine (r = 0.41-0.52). Standard THC units, calculated with average concentrations of THC in cannabis in the UK and unaided self-report measures of amount of cannabis used in grams showed the strongest correlation with THC-COOH in urine (r = 0.52, 95% bias-corrected and accelerated = 0.26-0.70).

CONCLUSIONS

The enhanced cannabis timeline followback (EC-TLFB) can provide a valid assessment of a comprehensive set of cannabis use measures including standard tetrahydrocannabinol units as well as and traditional TLFB assessments (e.g. frequency of use and grams of cannabis use).

CBD and THC in Special Populations: Pharmacokinetics and Drug-Drug Interactions

Cannabinoid use has surged in the past decade, with a growing interest in expanding cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) applications into special populations. Consequently, the increased use of CBD and THC raises the risk of drug-drug interactions (DDIs). Nevertheless, DDIs for cannabinoids, especially in special populations, remain inadequately investigated. While some clinical trials have explored DDIs between therapeutic drugs like antiepileptic drugs and CBD/THC, more potential interactions remain to be examined. This review summarizes the published studies on CBD and THC-drug interactions, outlines the mechanisms involved, discusses the physiological considerations in pharmacokinetics (PK) and DDI studies in special populations (including pregnant and lactating women, pediatrics, older adults, patients with hepatic or renal impairments, and others), and presents modeling approaches that can describe the DDIs associated with CBD and THC in special populations. The PK of CBD and THC in special populations remain poorly characterized, with limited studies investigating DDIs involving CBD/THC in these populations. Therefore, it is critical to evaluate potential DDIs between CBD/THC and medications that are commonly used in special populations. Modeling approaches can aid in understanding these interactions.

Cannabis use, health problems, and criminal offences in Germany: national and state-level trends between 2009 and 2021

The German federal government plans to decriminalise cannabis. The impact of this policy on use prevalence, cannabis-related health and legal problems cannot be fully anticipated and should be viewed in context with current trends. We used routine data on (a) cannabis use (population-based surveys), (b) cannabis-related diagnoses (ICD-10 code F12) in outpatient medical settings and (c) minor law offences (registered violations against the narcotics law for possessing small amounts) to analyse age and sex-specific trends by federal state between 2009 and 2021. To enable comparisons across time and federal state besides crude prevalence rates, age-standardised rates were calculated. Between 2009 and 2021, the age-standardised prevalence of cannabis use (5.7-10.6%), rate of diagnoses (1.1-3.7 per 1,000), and legal offences (1.8-3.1 per 1,000) increased, with the largest increase noted for cannabis-related diagnoses. Relatively, increases were most pronounced for older users (40-to-59-year-olds: use and offences; 35-to-44-year-olds: cannabis-related diagnoses) and rather stagnant for minors. Cannabis use and health problems appear to be more pronounced in Northern and city states, while no clear geographic trend was observed for law offences. Cannabis-related outpatient treatment demand has risen more steeply than use prevalence suggesting an increasing challenge for the health care system. Despite rising rates for documented offences, the long-term implications of law violations on social and occupational life are poorly understood but may be considered for evaluations of the proposed law changes.

Cannabis Dependence is Associated with Reduced Hippocampal Subregion Volumes Independently of Sex: Findings from an ENIGMA Addiction Working Group Multi-Country Study

Background: Males and females who consume cannabis can experience different mental health and cognitive problems. Neuroscientific theories of addiction postulate that dependence is underscored by neuroadaptations, but do not account for the contribution of distinct sexes. Further, there is little evidence for sex differences in the neurobiology of cannabis dependence as most neuroimaging studies have been conducted in largely male samples in which cannabis dependence, as opposed to use, is often not ascertained. Methods: We examined subregional hippocampus and amygdala volumetry in a sample of 206 people recruited from the ENIGMA Addiction Working Group. They included 59 people with cannabis dependence (17 females), 49 cannabis users without cannabis dependence (20 females), and 98 controls (33 females). Results: We found no group-by-sex effect on subregional volumetry. The left hippocampal cornu ammonis subfield 1 (CA1) volumes were lower in dependent cannabis users compared with non-dependent cannabis users (p<0.001, d=0.32) and with controls (p=0.022, d=0.18). Further, the left cornu ammonis subfield 3 (CA3) and left dentate gyrus volumes were lower in dependent versus non-dependent cannabis users but not versus controls (p=0.002, d=0.37, and p=0.002, d=0.31, respectively). All models controlled for age, intelligence quotient (IQ), alcohol and tobacco use, and intracranial volume. Amygdala volumetry was not affected by group or group-by-sex, but was smaller in females than males. Conclusions: Our findings suggest that the relationship between cannabis dependence and subregional volumetry was not moderated by sex. Specifically, dependent (rather than non-dependent) cannabis use may be associated with alterations in selected hippocampus subfields high in cannabinoid type 1 (CB1) receptors and implicated in addictive behavior. As these data are cross-sectional, it is plausible that differences predate cannabis dependence onset and contribute to the initiation of cannabis dependence. Longitudinal neuroimaging work is required to examine the time-course of the onset of subregional hippocampal alterations in cannabis dependence, and their progression as cannabis dependence exacerbates or recovers over time.

Cannabis use and cannabis use disorders and their treatment in the Europe

This paper introduces the special issue on cannabis use in Europe. It describes data on the prevalence of cannabis use in Europe and the more limited data on the prevalence of cannabis use disorders, one of the most common forms of drug problem treated in many countries in Europe. It summarises what research has indicated about the adverse effects of acute and chronic cannabis use and discusses potential health system responses that may reduce some of these harms. These include public education about the risks of cannabis use; screening and brief interventions in primary medical settings; and specialist treatment for cannabis use disorders. It briefly indicates the special issues that may need to be addressed in dealing with the high rates of comorbidity between cannabis use disorders, other types of drug use disorders, and common mental disorders.

Age differences in patterns of cannabis use among an online US sample of adults who consume cannabis frequently

Background: Cannabis use is increasing among middle-aged and older US adults, populations that are particularly vulnerable to the adverse effects of cannabis. Risks for adverse effects differ by cannabis use patterns, which have become increasingly heterogeneous. Nevertheless, little is known about age differences in such patterns.Objective: To investigate age differences in cannabis use patterns, comparing younger (age 18-49), middle-aged (age 50-64), and older adults (age ≥65).Methods: A total of 4,151 US adults with past 7-day cannabis consumption completed an online survey (35.1% male; 60.1% female; 4.8% identified as "other"). Regression models examined age differences in cannabis use patterns.Results: Compared to younger adults, middle-aged and older adults were more likely to consume cannabis during evening hours (50-64: adjusted odds ratio [aOR] = 2.98, 95% CI 2.24-3.96; ≥65: aOR = 4.23, 95 CI 2.82-6.35); by only one method (50-64: aOR = 1.67, 95% CI 1.34-2.09; ≥65: aOR = 3.38, 95 CI 2.24-5.09); primarily by smoking as the only method (50-64: aOR = 1.52, 95% CI 1.29-1.78; ≥65: aOR = 2.12, 95 CI 1.64-2.74); but less likely to consume concentrated cannabis products (concentrates) with extremely high %THC (50-64: aOR = 0.71, 95% CI 0.54-0.93; ≥65: aOR = 0.30, 95 CI 0.16-0.55). Age differences in cannabis use patterns were also observed between middle-aged and older adults.Conclusion: Findings suggest that middle-aged and older adults may engage in less risky cannabis use patterns compared to younger groups (e.g. lower likelihood of consuming highly potent concentrates). However, findings also underscore the importance of recognizing risks unique to these older demographics, such as smoking-related health events. Consequently, prevention strategies targeting such use patterns are needed.

Medicinal cannabis use among young adults during California's transition from legalized medical use to adult-use: a longitudinal analysis

Background: In 2016, California transitioned from legalized medical cannabis use to adult-use. Little is known about how this policy change affected medicinal cannabis use among young adults.Objectives: To identify longitudinal groups of medicinal cannabis users and concurrent changes in health- and cannabis use-related characteristics among young adults in Los Angeles between 2014 and 2021.Methods: Cannabis users (210 patients and 156 non-patients; 34% female; ages 18-26 at baseline) were surveyed annually across six waves. Longitudinal latent class analysis derived groups from two factors - cannabis patient status and self-reported medicinal use. Trajectories of health symptoms, cannabis use motives, and cannabis use (daily/near daily use, concentrate use, and problematic use) were estimated across groups.Results: Three longitudinal latent classes emerged: Recreational Users (39.3%) - low self-reported medicinal use and low-to-decreasing patient status; Recreational Patients (40.4%) - low self-reported medicinal use and high-to-decreasing patient status; Medicinal Patients (20.3%) - high self-reported medicinal use and high-to-decreasing patient status. At baseline, Medicinal Patients had higher levels of physical health symptoms and motives than recreational groups (p < .05); both patient groups reported higher level of daily/near daily and concentrate use (p < .01). Over time, mental health symptoms increased in recreational groups (p < .05) and problematic cannabis use increased among Recreational Patients (p < .01).Conclusions: During the transition to legalized adult-use, patterns of medicinal cannabis use varied among young adults. Clinicians should monitor increases in mental health symptoms and cannabis-related problems among young adults who report recreational - but not medicinal - cannabis use.

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

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

Countering online marketing and user endorsements with enhanced cannabis warning labels: An online experiment among at-risk youth and young adults

As cannabis legalization expands and online marketing intensifies, this study examines whether online social cues can amplify youth-targeted cannabis advertising and whether cannabis warning labels (CWLs) can counteract these influences. A U.S. online sample of 970 adolescents and 1776 young adults susceptible to cannabis use were recruited from Qualtrics in summer 2022. Each participant was randomly assigned to one of the 3 (CWLs: none vs. textual vs. pictorial) by 3 (comments: none vs. anti-cannabis vs. pro-cannabis) conditions in an online experiment. Participants were exposed to three online marketing posts promoting marijuana edibles (randomly selected from a large pool, N = 1260), each with either no warning label, a textual warning, or a pictorial warning (text and picture), and with either five comments (pro- or anti-cannabis in valence) or none. Results showed that among adolescents, pro-cannabis comments increased product appeal (vs. anti-cannabis comments: b = 0.18, p = .025; vs. no comments: b = 0.21, p = .021), and did so more than young adults. For adolescents, only pictorial warnings reduced product appeal (b = -0.20, p = .028). For young adults, both pictorial (b = -0.18, p = .002) and textual warnings (b = -0.12, p = .029) reduced product appeal. Furthermore, both textual (adolescents: b = -0.20, p = .004; young adults: b = -0.15, p = .005) and pictorial (adolescents: b = -0.30, p < .001; young adults: b = -0.18, p = .001) warnings reduced cannabis use intentions. Findings support requiring enhanced CWLs accompany online marketing ads.

[Cannabis use in teenage years: Results of the prevention radar from 2016 to 2023]

Trends des Cannabiskonsums in der Adoleszenz sollen von 2016 bis 2023 abgebildet werden. Basierend auf sieben Wellen des Präventionsradars, einer schulbasierten epidemiologischen Studie in der Sekundarstufe I, wurden die Lebenszeit- und Monatsprävalenzen des Cannabiskonsums von 12-bis 17-Jährigen für den Zeitraum von 2016 bis 2023 ermittelt. Der Auswertung lagen 54.242 Fragebögen mit Angaben zum Konsum von Cannabis zugrunde. Das Geschlechterverhältnis war ausgeglichen (50% weiblich). Das durchschnittliche Alter betrug 13,9 Jahre (SD=1,3). Von 2016 bis zum Ausbruch der COVID-19-Pandemie stieg die Lebenszeitprävalenz des Cannabiskonsums statistisch bedeutsam an, im ersten Jahr der Pandemie sank sie signifikant. Post-pandemisch hatten 12,3% (95 % KI: 11,6-13,1) der Heranwachsenden mindestens einmal in ihrem Leben Cannabis konsumiert. Dieser Wert liegt auf dem Niveau von 2016. Die Monatsprävalenz des Cannabiskonsums lag 2022/2023 bei 3,8% (95% KI: 3,4-4,3). Sowohl die Lebenszeit- als auch die Monatsprävalenz des Cannabiskonsums von Jungen liegen signifikant über den Werten der Mädchen. Angesichts der bekannten Risiken, die mit dem Cannabiskonsum im Jugendalter einhergehen können, ist es besorgniserregend, dass 2022/2023 etwa jeder achte Jugendliche bereits mit Cannabis experimentiert hatte. Konsequente verhältnis- und verhaltenspräventive Maßnahmen sind erforderlich, um den Cannabiskonsums im Teenageralter einzudämmen.

Unmet Healthcare Needs and Medical Cannabis Use Among Sexual and Gender Minoritized Adults in a High-Stigma Environment

Sexual and gender minoritized (SGM) individuals in high-stigma areas may use cannabis to cope with unmet healthcare needs and elevated stress. Adults in Oklahoma (Mage = 43.9[SD = 16.8], 54.5% female, 71.4% non-Hispanic White) completed a cross-sectional survey (August-September 2022). Logistic regression examined the association of SGM identity (SGM or non-SGM) with past-year unmet healthcare need (yes/no). Logistic and linear regressions also examined main and interactive effects of SGM identity and unmet healthcare needs on past-month medical cannabis use and number of relaxation/tension-reduction reasons for cannabis use endorsed. Analyses were unadjusted and adjusted for sociodemographic and healthcare characteristics. In adjusted analyses, SGM (vs. non-SGM) adults were more likely to report unmet healthcare needs (aOR = 2.24, 95% CI[1.47, 3.42], p < .001) and past-month medical cannabis use (aOR = 2.15 [1.07, 4.34], p = .033). In unadjusted analyses, SGM (versus non-SGM) adults and those with unmet healthcare needs (versus without) endorsed more relaxation/tension reduction reasons for cannabis use in separate main effects (ps < .029), and adults with unmet healthcare needs (vs. without) were more likely to report past-month medical cannabis use (OR = 2.31 [1.86, 2.88]). SGM identity X unmet healthcare need interactions did not emerge (ps > .05). SGM individuals in high-stigma environments may use cannabis to compensate for insufficient healthcare.

Examining the effect of cannabis cues on cannabis demand in sleep, driving, and typical drug-use contexts

PURPOSE

Given the expanding legal cannabis market in the U.S., it is vital to understand how context impacts cannabis use. Therefore, we explored the effect of cannabis cues and cannabis-use context on cannabis demand in 79 adults who reported smoking cannabis at least weekly.

METHODS

Participants completed a single laboratory session consisting of four hypothetical marijuana purchase tasks (MPTs) involving either a typical use situation or a driving or sleep context. The MPTs were alternated with exposure to cannabis or neutral picture cues based on block randomization by gender.

RESULTS

Cannabis cues increased self-reported craving for cannabis (p =.044) but did not significantly alter demand (ps =0.093-0.845). In the driving context, participants demonstrated a significant reduction in cannabis demand, indicated by lower intensity (p <0.001), Omax (p <0.001), and Pmax (p <0.001), breakpoint (p =.003), and higher α (p <0.001). The sleep context was associated with significantly greater α (p <0.006) but nonsignificant effects for other indices (ps =0.123-0.707). Finally, cannabis cues increased Omax (p =.013) and breakpoint (p =.035) in the sleep context but not in the typical-use context.

CONCLUSIONS

These findings suggest that cannabis-use behavior is sensitive to contingencies surrounding driving after cannabis use and may also be sensitive to sleep contexts in the presence of cannabis cues. Since this is the first study to examine driving and sleep contexts, we caution against drawing broad conclusions until future research is conducted to replicate these findings.

A preliminary randomized controlled trial of repetitive transcranial magnetic stimulation applied to the left dorsolateral prefrontal cortex in treatment seeking participants with cannabis use disorder

BACKGROUND

Cannabis use disorder (CUD) is a common and consequential disorder. When applied to the dorsolateral prefrontal cortex (DLPFC), repetitive transcranial magnetic stimulation (rTMS) reduces craving across substance use disorders and may have therapeutic clinical effects when applied in serial-sessions. The present study sought to preliminarily determine whether serial-sessions of rTMS applied to the DLPFC had a therapeutic effect in CUD.

METHODS

This study was a two-site, phase-2, double-blind, randomized-controlled-trial. Seventy-two treatment-seeking participants (37.5% Women, mean age 30.2±9.9SD) with ≥moderate-CUD were randomized to active or sham rTMS (Beam-F3, 10Hz, 20-total-sessions, two-sessions-per-visit, two-visits-per-week, with cannabis cues) while undergoing a three-session motivational enhancement therapy intervention. The primary outcome was the change in craving between pre- and post- treatment (Marijuana Craving Questionnaire Short-Form-MCQ-SF). Secondary outcomes included the number of weeks of abstinence and the number of days-per-week of cannabis use during 4-weeks of follow-up.

RESULTS

There were no significant differences in craving between conditions. Participants who received active-rTMS reported numerically, but not significantly, more weeks of abstinence in the follow-up period than those who received sham-rTMS (15.5%-Active; 9.3%-Sham; rate ratio = 1.66 [95% CI: 0.84, 3.28]; p=0.14). Participants who received active-rTMS reported fewer days-per-week of cannabis use over the final two-weeks of the follow-up period than those receiving sham-rTMS (Active vs. Sham: -0.72; Z=-2.33, p=0.02).

CONCLUSIONS

This trial suggests rTMS is safe and feasible in individuals with CUD and may have a therapeutic effect on frequency of cannabis use, though further study is needed with additional rTMS-sessions and a longer follow-up period.

Factors associated with drug use in prison: A systematic review of quantitative and qualitative evidence

BACKGROUND

About a third of people use drugs during their incarceration, which is associated with multiple adverse health and criminal justice outcomes. Many studies have examined factors associated with in-prison drug use, but this evidence has not yet been systematically reviewed. We aimed to systematically review and synthesise the evidence on factors related to drug use in prison.

METHODS

Three databases (PubMed, PsycINFO and Embase) were systematically searched as well as grey literature, for quantitative, qualitative and mixed-methods studies examining factors related to drug use inside prison. We excluded studies that did not explicitly measure in prison drug use or only measured alcohol and/or tobacco use. Study quality was assessed using the Newcastle Ottawa Scale (NOS) for quantitative studies and Critical Appraisal Skills Programme (CASP) for qualitative studies. The review was prospectively registered on PROSPERO (CRD42021295898).

RESULTS

Fifty-four studies met the inclusion criteria, reporting data on 26,399 people in prison. Most studies were of low or moderate-quality, and all used self-report to assess drug use. In quantitative studies, studies found that previous criminal justice involvement, poor prison conditions, pre-prison drug use and psychiatric diagnosis were positively associated with drug use in prison. In qualitative studies, reasons for drug use were closely linked to the prison environment lacking purposeful activity and the social context of the prison whereby drug use was seen as acceptable, necessary for cohesion and pressurised.

CONCLUSION

In the first systematic review of factors associated with drug use in prison, key modifiable risk factors identified from quantitative and qualitative studies were psychiatric morbidity and poor prison conditions. Non-modifiable factors included previous drug use and criminal history linked to substance use. Our findings indicate an opportunity to intervene and improve the prison environment to reduce drug use and associated adverse outcomes.

Association between cannabis use disorder and schizophrenia stronger in young males than in females

BACKGROUND

Previous research suggests an increase in schizophrenia population attributable risk fraction (PARF) for cannabis use disorder (CUD). However, sex and age variations in CUD and schizophrenia suggest the importance of examining differences in PARFs in sex and age subgroups.

METHODS

We conducted a nationwide Danish register-based cohort study including all individuals aged 16-49 at some point during 1972-2021. CUD and schizophrenia status was obtained from the registers. Hazard ratios (HR), incidence risk ratios (IRR), and PARFs were estimated. Joinpoint analyses were applied to sex-specific PARFs.

RESULTS

We examined 6 907 859 individuals with 45 327 cases of incident schizophrenia during follow-up across 129 521 260 person-years. The overall adjusted HR (aHR) for CUD on schizophrenia was slightly higher among males (aHR = 2.42, 95% CI 2.33-2.52) than females (aHR = 2.02, 95% CI 1.89-2.17); however, among 16-20-year-olds, the adjusted IRR (aIRR) for males was more than twice that for females (males: aIRR = 3.84, 95% CI 3.43-4.29; females: aIRR = 1.81, 95% CI 1.53-2.15). During 1972-2021, the annual average percentage change in PARFs for CUD in schizophrenia incidence was 4.8 among males (95% CI 4.3-5.3; p < 0.0001) and 3.2 among females (95% CI 2.5-3.8; p < 0.0001). In 2021, among males, PARF was 15%; among females, it was around 4%.

CONCLUSIONS

Young males might be particularly susceptible to the effects of cannabis on schizophrenia. At a population level, assuming causality, one-fifth of cases of schizophrenia among young males might be prevented by averting CUD. Results highlight the importance of early detection and treatment of CUD and policy decisions regarding cannabis use and access, particularly for 16-25-year-olds.

Legalization of marijuana or not? Opinions from over 38,000 residents in Taiwan

BACKGROUND

Marijuana is legal in many Western countries and Thailand. In Taiwan, Marijuana remains a category-2 narcotic; however, some legislative candidates recently advocated legalization of medical marijuana. This study surveyed a large sample of Taiwanese to gain a better understanding of the public's knowledge and attitudes towards legalizing marijuana.

METHODS

This cross-sectional mixed-methods study included demographic data and responses to a survey questionnaire, "Knowledge and Attitudes of Legalizing Marijuana" (KALM). The survey included 15 statements about four categories: public health, social impact, medical applications of THC (Δ9-tetrahydrocannabinol), and legal and tax consequences; and two yes/no questions about medical use and legalization of marijuana. Knowledge was scored as disagree = 0, no knowledge = 2, or agree = 4; attitude was scored from 0 = very unimportant to 4 = very important. Responses to an open-ended question asking for additional comments/concerns were analysed with content analysis. The survey was conducted from February 15 to March 1, 2023.

RESULTS

Data were analysed from 38,502 respondents, aged 15 to > 56 years. Most were female (67.1%) and parents (76.4%). Scores were higher for respondents who were parents, religious, ≥ 36 years of age, had a high-income status, no history of substance abuse, knowledge of medical marijuana, and did not support legalization of marijuana. Medical personnel had greater knowledge of marijuana, but their attitude indicated they viewed legalization as less important. In the open-ended question, many respondents requested more information about marijuana be provided to the public before considering legalization.

CONCLUSIONS

Taiwanese respondents considered legalization of marijuana a significant concern, especially as it relates to impacts on public health.

Association between non-medical cannabis legalization and emergency department visits for cannabis-induced psychosis

A major public health concern of cannabis legalization is that it may result in an increase in psychotic disorders. We examined changes in emergency department (ED) visits for cannabis-induced psychosis following the legalization and subsequent commercialization (removal of restrictions on retail stores and product types) of non-medical cannabis in Ontario, Canada (population of 14.3 million). We used health administrative data containing the cause of all ED visits to examine changes over three periods; 1) pre-legalization (January 2014-September 2018); 2) legalization with restrictions (October 2018 - February 2020); and 3) commercialization (March 2020 - September 2021). We considered subgroups stratified by age and sex and examined cocaine- and methamphetamine-induced psychosis ED visits as controls. During our study, there were 6300 ED visits for cannabis-induced psychosis. The restricted legalization period was not associated with changes in rates of ED visits for cannabis-induced psychosis relative to pre-legalization. The commercialization period was associated with an immediate increase in rates of ED visits for cannabis-induced psychosis (IRR 1.30, 95% CI 1.02-1.66) and no gradual monthly change; immediate increases were seen only for youth above (IRR 1.63, 1.27-2.08, ages 19-24) but not below (IRR 0.73 95%CI 0.42-1.28 ages, 15-18) the legal age of purchase, and similar for men and women. Commercialization was not associated with changes in rates of ED visits for cocaine- or methamphetamine-induced psychosis. This suggests that legalization with store and product restrictions does not increase ED visits for cannabis-induced psychosis. In contrast, cannabis commercialization may increase cannabis-induced psychosis presentations highlighting the importance of preventive measures in regions considering legalization.

Parallel trajectories of vaping and smoking cannabis and their associations with mental and physical well-being among young adults

BACKGROUND

Vaping and smoking are common modes of using cannabis (THC) among young adults, but little is known about how patterns of cannabis vaping and smoking unfold over time or how using one or both types of products may differently affect mental and physical well-being. This study examines parallel processes of cannabis vaping and smoking over 5 years and mental and physical outcomes in a sample of young adults.

METHODS

Annual surveys were conducted between 2016 and 2022 with a mostly California-based cohort of 2428 young adults. Parallel process growth mixture models examined trajectories of past-month frequency of cannabis vaping and smoking from ages 20 - 25. Classes were extracted based on parallel trajectories of vaped and smoked product use. Models assessed differences in self-reported mental (anxiety, depression) and physical (ailments, subjective overall) well-being outcomes in young adulthood across classes, adjusting for demographic characteristics and mental and physical well-being at pre-baseline (average age 19).

RESULTS

Four cannabis vaping/smoking classes emerged: low use of cannabis (84.7%), decreasing smoking, low-moderate vaping (7.1%), stable moderate smoking, decreasing vaping (4.6%), and rapid increasing dual use (3.4%). Classes were similar on physical well-being indicators in young adulthood. The rapid increasing dual use class showed higher anxiety and depressive symptoms compared to other classes.

CONCLUSION

Progression to higher frequency of both vaping and smoking cannabis in young adulthood may contribute to poorer mental well-being compared to other use patterns. Targeted efforts to reduce dual vaping and smoking in young people who use cannabis may be needed.

Association of cannabis, cannabidiol and synthetic cannabinoid use with mental health in UK adolescents

BACKGROUND

Cannabis has been associated with poorer mental health, but little is known of the effect of synthetic cannabinoids or cannabidiol (often referred to as CBD).

AIMS

To investigate associations of cannabis, synthetic cannabinoids and cannabidiol with mental health in adolescence.

METHOD

We conducted a cross-sectional analysis with 13- to 14-year-old adolescents across England and Wales in 2019-2020. Multilevel logistic regression was used to examine the association of lifetime use of cannabis, synthetic cannabinoids and cannabidiol with self-reported symptoms of probable depression, anxiety, conduct disorder and auditory hallucinations.

RESULTS

Of the 6672 adolescents who participated, 5.2% reported using of cannabis, 1.9% reported using cannabidiol and 0.6% reported using synthetic cannabinoids. After correction for multiple testing, adolescents who had used these substances were significantly more likely to report a probable depressive, anxiety or conduct disorder, as well as auditory hallucinations, than those who had not. Adjustment for socioeconomic disadvantage had little effect on associations, but weekly tobacco use resulted in marked attenuation of associations. The association of cannabis use with probable anxiety and depressive disorders was weaker in those who reported using cannabidiol than those who did not. There was little evidence of an interaction between synthetic cannabinoids and cannabidiol.

CONCLUSIONS

To our knowledge, this study provides the first general population evidence that synthetic cannabinoids and cannabidiol are associated with probable mental health disorders in adolescence. These associations require replication, ideally with prospective cohorts and stronger study designs.

Perceptions of cannabis use risk to mental health among youth in Canada, England and the United States from 2017 to 2021

BACKGROUND

There is little research examining perceptions of cannabis use risk to mental health in countries with differing cannabis regulations. This study therefore examines such perceptions among youth between 2017 and 2021 in Canada (non-medical cannabis legalized in October 2018), England (highly-restricted medical cannabis legalized November 2018), and the US (non-medical cannabis legal in some states).

METHODS

Seven repeat cross-sectional online surveys were conducted between July 2017 to August 2021 among youth aged 16-19 in Canada (N=29,420), England (N=28,155), and the US (N=32,974). Logistic regression models, stratified by country, were used to examine perceptions of cannabis use risk to mental health over time, adjusting for age group, sex, race/ethnicity, cannabis use and, for the US only, state-level cannabis legalization.

RESULTS

Perceptions that cannabis use posed "no risk" to mental health decreased between July 2017 and August 2021 in Canada (6.1-4.4%; AOR=0.64, 95% CI=0.52-0.78) and the US (14.0-11.3%; AOR=0.74, 0.65-0.84) but not England (3.7-4.5%; AOR=1.21, 0.97-1.52). No significant changes were observed from immediately before (August 2018) to after (August 2019) legalization of non-medical cannabis in Canada (AOR=0.99, 0.83-1.20) or highly-restricted medical cannabis in England (AOR=0.90, 0.70-1.17). In the US, perceptions of "no risk" were more likely in states where cannabis use was illegal (15.0%) compared with legal non-medical (12.2%) (AOR=0.68, 0.63-0.74).

CONCLUSION

There were modest decreases in perceptions that cannabis use poses no risk to mental health in Canada and the US between 2017 and 2021 but no clear association with cannabis legalization status.

Targeting corticostriatal transmission for the treatment of cannabinoid use disorder

It is generally assumed that the rewarding effects of cannabinoids are mediated by cannabinoid CB1 receptors (CB1Rs) the activation of which disinhibits dopaminergic neurons in the ventral tegmental area (VTA). However, this mechanism cannot fully explain novel results indicating that dopaminergic neurons also mediate the aversive effects of cannabinoids in rodents, and previous results showing that preferentially presynaptic adenosine A2A receptor (A2AR) antagonists counteract self-administration of Δ-9-tetrahydrocannabinol (THC) in nonhuman primates (NHPs). Based on recent experiments in rodents and imaging studies in humans, we propose that the activation of frontal corticostriatal glutamatergic transmission constitutes an additional and necessary mechanism. Here, we review evidence supporting the involvement of cortical astrocytic CB1Rs in the activation of corticostriatal neurons and that A2AR receptor heteromers localized in striatal glutamatergic terminals mediate the counteracting effects of the presynaptic A2AR antagonists, constituting potential targets for the treatment of cannabinoid use disorder (CUD).

Cannabis Use Patterns and Whole-Blood Cannabinoid Profiles of Emergency Department Patients With Suspected Cannabinoid Hyperemesis Syndrome

STUDY OBJECTIVES

The objectives of this study were to characterize the detailed cannabis use patterns (eg, frequency, mode, and product) and determine the differences in the whole-blood cannabinoid profiles during symptomatic versus asymptomatic periods of participants with suspected cannabinoid hyperemesis syndrome recruited from the emergency department (ED) during a symptomatic episode.

METHODS

This is a prospective observational cohort study of participants with symptomatic cyclic vomiting onset after chronic cannabis use. Standardized assessments were conducted to evaluate for lifetime and recent cannabis use, cannabis use disorder, and cannabis withdrawal symptoms. Quantitative whole-blood cannabinoid testing was performed at 2 times, first when symptomatic (ie, baseline) and at least 2 weeks after the ED visit when asymptomatic. The differences in cannabinoid concentrations were compared between symptomatic and asymptomatic testing. The study was conducted from September 2021 to August 2022.

RESULTS

There was a difference observed between delta-9-tetrahydrocannabinol metabolites, but not the parent compound during symptomatic episodes and asymptomatic periods. Most participants (84%) reported using cannabis > once per day (median 3 times per day on weekdays, 4 times per day on weekends). Hazardous cannabis use was universal among participants; the mean cannabis withdrawal discomfort score was 13, indicating clinically significant rates of cannabis withdrawal symptoms with cessation of use. Most participants (79%) previously tried to stop cannabis use, but a few (13%) of them had sought treatment.

CONCLUSION

Patients presenting to the ED with cannabinoid hyperemesis syndrome have high cannabis use disorder scores. Further studies are needed to better understand the influence of THC metabolism and concentrations on symptomatic cyclic vomiting.