Trends of cannabis use and related harms before and after legalization for recreational purpose in a developing country in Asia.

BACKGROUND: Thailand was the first country in Asia to legalize the use and purchase of cannabis leaves in February 2021 and the whole plant in June 2022 after the 2019 allowance for medical purposes. The study explored trends in cannabis use in Thailand before and after the recreational cannabis allowance was imposed. METHODS: Cannabis and other variables of substance use, cannabis use disorder, and attitude towards cannabis of the Thai population aged 18 to 65 years in 2019 (n = 5,002), 2020 (n = 5,389) and 2021 (n = 5,669) were obtained from annual surveys conducted in the last two months of each year by the Centre for Addiction Studies. The surveys were repeat cross-sectional surveys of the general population of Thailand. Repeated variables from at least two annual surveys were included for analysis using the Chi-square test and the t-test. RESULTS: The prevalence of cannabis use in the past year had increased from 2.2% in 2019 to 2.5% and 4.2% in 2020 and 2021 respectively, while those of methamphetamine, alcohol, and tobacco use had decreased. Trends in past-year drinking/eating cannabis products had increased, especially among the middle age group (40-49 years) from 2.1% (95% confidence interval (CI): 1.3, 3.1) in 2019 and 1.1% (95% CI: 0.6, 1.9) in 2020 to 3.8% (95% CI: 2.8, 5.0) in 2021. The younger population aged 18-19 had an increase in cannabis smoking from 0.9% (95% CI: 0.1, 3.3) in 2019 to 2.0% (95% CI: 0.5, 5.1) and 2.2% (95% CI: 0.7, 5.1) in 2020 and 2021 respectively. Symptoms of cannabis use disorder among cannabis users increased from 2019 to 2020 and then reversed afterwards in 2021. Thais had greater health knowledge about the benefits and harms of cannabis and had attitudes toward more harm of cannabis in 2021; however, 35.6% or a third of the sample in 2021 truly believed that cannabis was a cure for cancer, and 23.2% or one-fourth were uncertain or did not believe that cannabis was addictive. CONCLUSIONS: Although most of the substances had a lower prevalence of use during the COVID-19 pandemic in Thailand, cannabis had a higher use after legalization. Thai youth had a growing trend to smoke cannabis.

Alcohol and cannabis use in traffic-related injuries in Mexico City.

BACTERKGROUND: There is debate on whether cannabis affects road traffic injuries (RTIs) separately from the effects of alcohol. Our goals are to report the possible increase in risk of an RTI among alcohol and cannabis users by type of exposure (biological, self-reported and combined) and the possible interaction of alcohol and cannabis in patients with an RTI in an emergency department in Mexico City. METHODS: A case-crossover study with 433 cases of RTI (as a pedestrian, driver or passenger) during the period January-April 2022. A breath sample, an oral sample for cannabis detection and self-reported alcohol and cannabis use 6 hours prior to the RTI and in two control periods were used. We report ORs and 95% CIs from conditional logistic regressions for the case-crossover estimates. RESULTS: Alcohol alone increased the risk of an RTI (OR=6.02, 95% CI 3.29 to 10.99) for most RTIs, regardless of whether we used information from self-reports or a breath sample in the hazard period. Conversely, cannabis only increased the RTI when we added information in the hazard period from self-reports or oral samples. Nevertheless, this increase in risk disappeared (OR=2.06, 95% CI 0.90 to 4.70) among those who only used cannabis. We also found no evidence of interaction between alcohol and cannabis in the risk of an RTI. CONCLUSIONS: Alcohol is the most commonly used substance in Mexico and a high-risk factor for RTI in Mexico City. Although cannabis alone was not associated with an RTI, continuous monitoring of its effects is required.

Alcohol, cannabis, and nicotine use have distinct associations with COVID-19 pandemic-related experiences: An exploratory Bayesian network analysis across two timepoints.

BACKGROUND: Substance use trends during the COVID-19 pandemic have been extensively documented. However, relatively less is known about the associations between pandemic-related experiences and substance use. METHOD: In July 2020 and January 2021, a broad U.S. community sample (N = 1123) completed online assessments of past month alcohol, cannabis, and nicotine use and the 92-item Epidemic-Pandemic Impacts Inventory, a multidimensional measure of pandemic-related experiences. We examined links between substance use frequency, and pandemic impact on emotional, physical, economic, and other key domains, using Bayesian Gaussian graphical networks in which edges represent significant associations between variables (referred to as nodes). Bayesian network comparison approaches were used to assess the evidence of stability (or change) in associations between the two timepoints. RESULTS: After controlling for all other nodes in the network, multiple significant edges connecting substance use nodes and pandemic-experience nodes were observed across both time points, including positive- (r range 0.07-0.23) and negative-associations (r range -0.25 to -0.11). Alcohol was positively associated with social and emotional pandemic impacts and negatively associated with economic impacts. Nicotine was positively associated with economic impact and negatively associated with social impact. Cannabis was positively associated with emotional impact. Network comparison suggested these associations were stable across the two timepoints. CONCLUSION: Alcohol, nicotine, and cannabis use had unique associations to a few specific domains among a broad range of pandemic-related experiences. Given the cross-sectional nature of these analyses with observational data, further investigation is needed to identify potential causal links.

CANreduce-SP-adding psychological support to web-based adherence-focused guided self-help for cannabis users: study protocol for a three-arm randomized control trial.

BACKGROUND: Cannabis is the most-frequently used illicit drug in Europe. Over the last few years in Spain, treatment demand has increased, yet most cannabis users do not seek treatment despite the related problems. A web-based self-help tool, like CANreduce 2.0, could help these users to control their consumption. METHODS: This study protocol describes a three-arm randomized controlled trial (RCT) comparing the effectiveness of three approaches, in terms of reducing cannabis use among problematic cannabis users, the first two treatment arms including the Spanish version of CANreduce 2.0 (an adherence-focused, guidance-enhanced, web-based self-help tool) (1) with and (2) without psychological support; and the third group (3) treatment as usual (TAU). Study hypotheses will be tested concerning the primary outcome: change in the number of days of cannabis use over the previous week, comparing assessments at 6 weeks and 3 and 6 months follow-up between groups and against baseline. Secondary outcomes related to cannabis use will be tested similarly. Mental disorders will be explored as predictors of adherence and outcomes. Analyses will be performed on an intention-to-treat basis, then verified by complete case analyses. DISCUSSION: This study will test how effective the Spanish version of CANreduce 2.0 (CANreduce-SP) is at reducing both the frequency and quantity of cannabis use in problematic users and whether adding psychological support increases its effectiveness. TRIAL REGISTRATION: This trial is registered with the Clinical Trials Protocol Registration and Results System (PRS) number: NCT04517474 . Registered 18 August 2020, (Archived by archive.is https://archive.is/N1Y64 ). The project commenced in November 2020 and recruitment is anticipated to end by November 2022.

The association between preconception cannabis use and depression and anxiety during pregnancy.

OBJECTIVE: Cannabis use among individuals of reproductive age has increased with cannabis legalization and heightened stress during the COVID-19 pandemic. Our study provides data on preconception cannabis use and cannabis use disorder (CUD) during the pandemic and models the association between preconception cannabis use and depression and anxiety during pregnancy. METHODS: Data on substance use and depression and anxiety symptoms were collected from questionnaires and the Structured Clinical Interview for DSM-5 (SCID-5) from pregnant individuals in Oregon in 2019-2022. Linear regression was used to model the association between the frequency of preconception cannabis use and scores on the Center for Epidemiological Studies of Depression-Revised (CESD-R) and Beck Anxiety Inventory (BAI). RESULTS: The prevalence of preconception cannabis use was 27.8% among 227 study participants. CUD was diagnosed in 19% of cannabis users, or 5.3% of the overall sample. Daily cannabis use, compared to rare/never use, was associated with increases in CESD-R (ß = 6.22, p 0.029) and BAI (ß = 4.71, p 0.045) scores. CONCLUSIONS: Cannabis use and CUD are common among individuals of reproductive age. Given the association between preconception cannabis use and depression and anxiety during pregnancy, more attention is needed on screening and counseling of cannabis use among people of reproductive age.

The effects of the 4/20 cannabis holiday and adult-use cannabis legalization on medical cannabis sales and medical cannabis patient registration in Arizona.

BACKGROUND: This study examined whether the 4/20 cannabis holiday was associated with increases in medical cannabis sales from licensed dispensaries in Arizona from 2018-2021, and whether adult-use cannabis legalization (the vote in November 2020 and retail sales in January 2021) was associated with declines in medical cannabis sales and in the number of registered medical patients. METHODS: Data came from the Arizona Medical Marijuana Program monthly reports from January 2018-December 2021. The reports show daily sales from licensed medical cannabis dispensaries (i.e., the number of medical cannabis dispensary transactions and the amount of cannabis sold in pounds), which we averaged by week, and show the number of registered medical cannabis patients each month. Autoregressive integrated moving average models were used to test changes in these outcomes associated with the 4/20 cannabis holiday and with legalization of adult-use cannabis. RESULTS: During the week of the 4/20 cannabis holiday, medical cannabis dispensary transactions abruptly increased by an average of 2,319.4 transactions each day (95% CI: 1636.1, 3002.7), and the amount of medical cannabis sold increased by an average of 120.3 pounds each day (95% CI: 99.3-141.3). During the first week of adult-use cannabis sales in late January 2021, medical cannabis dispensary transactions abruptly decreased by an average of 5,073 transactions each day (95% CI: -5,929.5, -4216.7), and the amount of medical cannabis sold decreased by an average of 119.1 pounds each day (95% CI: -144.2, -94.0). Moreover, medical cannabis sales continued to gradually decline each week after the start of adult-use retail sales, with declines in sales preceding declines in registered patients. By December 2021, slightly over a year after the vote to legalize adult-use cannabis, the actual number of registered medical cannabis patients fell short of the forecasted number, had adult-use not been legalized, by 36.5%. Moreover, the number of medical dispensary transactions and the amount of medical cannabis sold fell short of expectations, had adult-use cannabis not been legalized, by 58% and 53%, respectively. CONCLUSIONS: Findings document the blurred boundary between medical and non-medical cannabis use and are consistent with the possibility that medical cannabis legalization contributes to increases in adult cannabis use and dependence.

Antiviral activities of hemp cannabinoids.

Hemp is an understudied source of pharmacologically active compounds and many unique plant secondary metabolites including more than 100 cannabinoids. After years of legal restriction, research on hemp has recently demonstrated antiviral activities in silico, in vitro, and in vivo for cannabidiol (CBD), Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), and several other cannabinoids against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), human immunodeficiency virus (HIV), and γ-herpes viruses. Mechanisms of action include inhibition of viral cell entry, inhibition of viral proteases, and stimulation of cellular innate immune responses. The anti-inflammatory properties of cannabinoids are also under investigation for mitigating the cytokine storm of COVID-19 and controlling chronic inflammation in people living with HIV. Retrospective clinical studies support antiviral activities of CBD, Δ9-THC, and cannabinoid mixtures as do some prospective clinical trials, but appropriately designed clinical trials of safety and efficacy of antiviral cannabinoids are urgently needed.

Cannabis use among cancer survivors before and during the COVID-19 pandemic, 2019-2021.

We estimated the prevalence of past 30-day cannabis use, evaluated reasons for use, and identified individual-level factors associated with cannabis use among cancer survivors before (2019) and during (2020 and 2021) the COVID-19 pandemic. Cancer survivors, aged 18 years and older, were identified from the 2019 (n = 8185), 2020 (n = 11 084), and 2021 (n = 12 248) Behavioral Risk Factor Surveillance System. Prevalence of past 30-day cannabis use among survivors held steady through the pandemic (8.7%, 7.4%, and 8.4% in 2019, 2020 and 2021, respectively). Of those who used cannabis, 48.7% used it for medical reasons in 2019, 54.5% in 2020, and 43.5% in 2021. Survivors were more likely to report past 30-day cannabis use if they were younger, male, current or former tobacco smokers, and binge alcohol consumers and if they experienced poor mental health in the past 30-days. Our study identified subpopulations of cancer survivors that need to be targeted for evidence-informed discussions about cannabis use.

Ingestion of Illicit Substances by Young Children Before and During the COVID-19 Pandemic.

Importance: Information about the trend in illicit substance ingestions among young children during the pandemic is limited. Objectives: To assess immediate and sustained changes in overall illicit substance ingestion rates among children younger than 6 years before and during the COVID-19 pandemic and to examine changes by substance type (amphetamines, benzodiazepines, cannabis, cocaine, ethanol, and opioids) while controlling for differing statewide medicinal and recreational cannabis legalization policies. Design, Setting, and Participants: Retrospective cross-sectional study using an interrupted time series at 46 tertiary care children's hospitals within the Pediatric Health Information System (PHIS). Participants were children younger than 6 years who presented to a PHIS hospital for an illicit substance(s) ingestion between January 1, 2017, and December 31, 2021. Data were analyzed in February 2023. Exposure: Absence or presence of the COVID-19 pandemic. Main Outcome(s) and Measure(s): The primary outcome was the monthly rate of encounters for illicit substance ingestions among children younger than 6 years defined by International Statistical Classification of Diseases, Tenth Revision, Clinical Modification diagnosis code(s) for poisoning by amphetamines, benzodiazepines, cannabis, cocaine, ethanol, and opioids. The secondary outcomes were the monthly rate of encounters for individual substances. Results: Among 7659 children presenting with ingestions, the mean (SD) age was 2.2 (1.3) years and 5825 (76.0%) were Medicaid insured/self-pay. There was a 25.6% (95% CI, 13.2%-39.4%) immediate increase in overall ingestions at the onset of the pandemic compared with the prepandemic period, which was attributed to cannabis, opioid, and ethanol ingestions. There was a 1.8% (95% CI, 1.1%-2.4%) sustained monthly relative increase compared with prepandemic trends in overall ingestions which was due to opioids. There was no association between medicinal or recreational cannabis legalization and the rate of cannabis ingestion encounters. Conclusions and Relevance: In this study of illicit substance ingestions in young children before and during the COVID-19 pandemic, there was an immediate and sustained increase in illicit substance ingestions during the pandemic. Additional studies are needed to contextualize these findings in the setting of pandemic-related stress and to identify interventions to prevent ingestions in face of such stress, such as improved parental mental health and substance treatment services, accessible childcare, and increased substance storage education.

Pandemic-related life changes and adolescent initiation of cannabis and tobacco/nicotine use.

BACKGROUND: The COVID-19 pandemic required the public to alter their daily lives drastically. For adolescents, school closures and social isolation added further challenges to a stressful stage of life, potentially increasing the likelihood of substance use initiation. This study explored the relationship between adolescent substance use initiation and negative life changes due to COVID-19. METHODS: Students from 9 high schools (N = 2478) in Los Angeles County were surveyed as 9th graders in the 2019-2020 school year and re-surveyed in 10th and 11th grades as part of an ongoing longitudinal study. Two logistic regression models were conducted to test hypotheses that negative life changes due to the COVID-19 pandemic increases the odds of initiation of both tobacco/nicotine products and cannabis products, controlling for sex, age, and race/ethnicity. RESULTS: The final analytic sample included adolescents in 10th grade who were never-users of tobacco/nicotine (N = 809) and cannabis (N = 837). The odds of initiating cannabis use increased by 6.42% for every 1 standard deviation increase in the COVID-19 negative daily life changes index [AOR: 1.063; 95% CI: 1.010, 1.121]. The association between the COVID-19 negative daily life changes index and tobacco/nicotine use initiation was not significant. DISCUSSION: Adolescents who experienced life changes due to COVID-19 were more likely to initiate cannabis use, but not tobacco/nicotine use. Results identify a need for early intervention efforts to promote effective coping skills and prevent cannabis initiation among adolescents during a wide-scale stressor, such as COVID-19.

Cannabis companies and the sponsorship of scientific research: A cross-sectional Canadian case study.

Corporations across sectors engage in the conduct, sponsorship, and dissemination of scientific research. Industry sponsorship of research, however, is associated with research agendas, outcomes, and conclusions that are favourable to the sponsor. The legalization of cannabis in Canada provides a useful case study to understand the nature and extent of the nascent cannabis industry's involvement in the production of scientific evidence as well as broader impacts on equity-oriented research agendas. We conducted a cross-sectional, descriptive, meta-research study to describe the characteristics of research that reports funding from, or author conflicts of interest with, Canadian cannabis companies. From May to August 2021, we sampled licensed, prominent Canadian cannabis companies, identified their subsidiaries, and searched each company name in the PubMed conflict of interest statement search interface. Authors of included articles disclosed research support from, or conflicts of interest with, Canadian cannabis companies. We included 156 articles: 82% included at least one author with a conflict of interest and 1/3 reported study support from a Canadian cannabis company. More than half of the sampled articles were not cannabis focused, however, a cannabis company was listed amongst other biomedical companies in the author disclosure statement. For articles with a cannabis focus, prevalent topics included cannabis as a treatment for a range of conditions (15/72, 21%), particularly chronic pain (6/72, 8%); as a tool in harm reduction related to other substance use (10/72, 14%); product safety (10/72, 14%); and preclinical animal studies (6/72, 8%). Demographics were underreported in empirical studies with human participants, but most included adults (76/84, 90%) and, where reported, predominantly white (32/39, 82%) and male (49/83, 59%) participants. The cannabis company-funded studies included people who used drugs (37%) and people prescribed medical cannabis (22%). Canadian cannabis companies may be analogous to peer industries such as pharmaceuticals, alcohol, tobacco, and food in the following three ways: sponsoring research related to product development, expanding indications of use, and supporting key opinion leaders. Given the recent legalization of cannabis in Canada, there is ample opportunity to create a policy climate that can mitigate the harms of criminalization as well as impacts of the "funding effect" on research integrity, research agendas, and the evidence base available for decision-making, while promoting high-priority and equity-oriented independent research.

Shifts in medical cannabis use in Canada during the COVID-19 pandemic. / Changements observés au Canada dans la consommation de cannabis à des fins médicales pendant la pandémie de COVID-19.

INTRODUCTION: The COVID-19 pandemic has had widespread secondary negative health impacts including loss of material security and exacerbation of mental illness in at-risk populations. While increases in the nonmedical use of certain substances, including cannabis, have been observed in samples of the Canadian population, no research has documented COVID-concurrent shifts in medical cannabis use in Canada. METHODS: Data were derived from the 2021 Canadian Cannabis Patient Survey, an online survey administered in May 2021 to people authorized to use medical cannabis recruited from one of two Canadian licensed medical cannabis producers. McNemar tests assessed for changes in past 3-month medical cannabis frequency from before to during the pandemic. We explored correlates of increasing frequency of cannabis use since before the pandemic in bivariable and multivariable logistic models. RESULTS: In total, 2697 respondents (49.1% women) completed the survey. Daily medical cannabis use increased slightly but significantly from before the pandemic (83.2%) to during the pandemic (90.3% at time of survey; p < 0.001). Factors significantly associated with increasing frequency of medical cannabis use included female gender, younger age, pandemic-related job loss, primary cannabis use to manage mental health, prescription drug use and nonmedical cannabis use (p < 0.05). CONCLUSION: There were slight shifts towards higher frequency of medical cannabis use after the onset of the COVID-19 pandemic. While short- and long-term impacts of cannabis use on pandemic-related mental distress are unknown, clinicians working with patients who use medical cannabis should be aware of possible changes in use patterns during the pandemic.

Digital interventions for substance use disorders in young people: rapid review.

BACKGROUND: Young people are disproportionately more likely than other age groups to use substances. The rise in substance use and related harms, including overdose, during the Covid-19 pandemic has created a critical need for more innovative and accessible substance use interventions. Digital interventions have shown effectiveness and can provide more engaging, less stigmatizing, and accessible interventions that meet the needs of young people. This review provides an overview of recent literature on the nature of recently published digital interventions for young people in terms of technologies used, substances targeted, intended outcomes and theoretical or therapeutic models employed. METHODS: Rapid review methodology was used to identify and assess the literature on digital interventions for young people. An initial keyword search was conducted using MEDLINE the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database (HTA) and PROSPERO for the years 2015-2020, and later updated to December 2021. Following a title/abstract and full-text screening of articles, and consensus decision on study inclusion, the data extraction process proceeded using an extraction grid developed for the study. Data synthesis relied on an adapted conceptual framework by Stockings, et al. that involved a three-level treatment spectrum for youth substance use (prevention, early intervention, and treatment) for any type of substance. RESULTS: In total, the review identified 43 articles describing 39 different digital interventions. Most were early interventions (n = 28), followed by prevention interventions (n = 6) and treatment interventions (n = 5). The identified digital technologies included web-based (n = 14), game-based (n = 10), mobile-based (n = 7), and computer-based (n = 5) technologies, and virtual reality (n = 3). Most interventions targeted alcohol use (n = 20) followed by tobacco/nicotine (n = 5), cannabis (n = 2), opioids (n = 2), ketamine (1) and multiple, or any substances (n = 9). Most interventions used a personalized or normative feedback approach and aimed to effect behaviour change as the intended outcome. Interestingly, a harm reduction approach guided only one of the 39 interventions. CONCLUSIONS: While web-based interventions represented the most common type of technology, more recently developed immersive and interactive technologies such as virtual reality and game-based interventions call for further exploration. Digital interventions focused mainly on alcohol use, reflecting less concern for tobacco, cannabis, co-occurring substance use, and illicit drug use. Specifically, the recent exacerbation in the opioid crisis throughout North American underlines the urgent need for more prevention-oriented digital interventions for opioid use. The uptake of digital interventions among youth also depends on the incorporation of harm reduction approaches.

Mental Health Conditions- and Substance Use-Associated Emergency Department Visits during the COVID-19 Pandemic in Nevada, USA.

Background-Mental health conditions and substance use are linked. During the COVID-19 pandemic, mental health conditions and substance use increased, while emergency department (ED) visits decreased in the U.S. There is limited information regarding how the pandemic has affected ED visits for patients with mental health conditions and substance use. Objectives-This study examined the changes in ED visits associated with more common and serious mental health conditions (suicidal ideation, suicide attempts, and schizophrenia) and more commonly used substances (opioids, cannabis, alcohol, and cigarettes) in Nevada during the COVID-19 pandemic in 2020 and 2021 compared with the pre-pandemic period. Methods-The Nevada State ED database from 2018 to 2021 was used (n = 4,185,416 ED visits). The 10th Revision of the International Classification of Diseases identified suicidal ideation, suicide attempts, schizophrenia, and the use of opioids, cannabis, alcohol, and cigarette smoking. Seven multivariable logistic regression models were developed for each of the conditions after adjusting for age, gender, race/ethnicity, and payer source. The reference year was set as 2018. Results-During both of the pandemic years (2020 and 2021), particularly in 2020, the odds of ED visits associated with suicidal ideation, suicide attempts, schizophrenia, cigarette smoking, and alcohol use were all significantly higher than those in 2018. Conclusions-Our findings indicate the impact of the pandemic on mental health- and substance use-associated ED visits and provide empirical evidence for policymakers to direct and develop decisive public health initiatives aimed at addressing mental health and substance use-associated health service utilization, especially during the early stages of large-scale public health emergencies, such as the COVID-19 pandemic.

Effects of Cannabidiol on Innate Immunity: Experimental Evidence and Clinical Relevance.

Cannabidiol (CBD) is the main non-psychotropic cannabinoid derived from cannabis (Cannabis sativa L., fam. Cannabaceae). CBD has received approval by the Food and Drug Administration (FDA) and European Medicines Agency (EMA) for the treatment of seizures associated with Lennox-Gastaut syndrome or Dravet syndrome. However, CBD also has prominent anti-inflammatory and immunomodulatory effects; evidence exists that it could be beneficial in chronic inflammation, and even in acute inflammatory conditions, such as those due to SARS-CoV-2 infection. In this work, we review available evidence concerning CBD's effects on the modulation of innate immunity. Despite the lack so far of clinical studies, extensive preclinical evidence in different models, including mice, rats, guinea pigs, and even ex vivo experiments on cells from human healthy subjects, shows that CBD exerts a wide range of inhibitory effects by decreasing cytokine production and tissue infiltration, and acting on a variety of other inflammation-related functions in several innate immune cells. Clinical studies are now warranted to establish the therapeutic role of CBD in diseases with a strong inflammatory component, such as multiple sclerosis and other autoimmune diseases, cancer, asthma, and cardiovascular diseases.

Puff, Puff, Don't Pass: harm reduction for cannabis use during a viral respiratory pandemic.

BACKGROUND: Prior to the COVID-19 pandemic, cannabis use social practices often involved sharing prepared cannabis (joints/blunts/cigarettes) and cannabis-related paraphernalia. Previous studies have demonstrated that sharing paraphernalia for cannabis, tobacco, and crack cocaine is a risk factor for respiratory viral and bacterial infections. Although COVID-19 is a respiratory viral infection that spreads through droplets and airborne transmission, it is unclear if many individuals adopted harm reduction practices around sharing cannabis. This study: quantifies the prevalence of sharing prepared non-medical cannabis and cannabis-related paraphernalia reported before and during the pandemic; assesses changes in sharing of non-medical cannabis from before to during the pandemic; assess the association between frequency of non-medical cannabis use and sharing of cannabis during the pandemic; and describes how respondents obtained their cannabis and the reasons for changing their cannabis use during the pandemic to explain differences in sharing patterns. METHODS: This cross-sectional study used data collected from an anonymous, US-based web survey on cannabis-related behaviors from August to September 2020 (n = 1833). Participants were included if they reported using a mode of inhalation for non-medical cannabis consumption. We calculated proportional changes in sharing cannabis before/during the COVID-19 pandemic. Associations between frequency of cannabis use and cannabis sharing during the COVID-19 pandemic were assessed using logistic regression analysis. RESULTS: Overall, 1,112 participants reported non-medical cannabis use; 925 (83.2%) reported a mode of cannabis inhalation. More respondents reported no sharing during (24.9%) than before the pandemic (12.4%; p < 0.01); less respondents shared most of the time (19.5% before; 11.2% during; p < 0.01) and always during the pandemic (5.2% before; 3.1% during; p < 0.01). After adjusting for covariates, the odds of any sharing during the pandemic for those who reported ≥ weekly cannabis use was 0.53 (95% CI 0.38, 0.75) compared to those who reported ≤ monthly. CONCLUSIONS: Sharing of prepared cannabis and cannabis-related paraphernalia decreased during the COVID-19 pandemic compared to before the pandemic. This finding suggests potential risk mitigation strategies taken by participants for COVID-19 prevention either directly through behavior change or indirectly through adherence to COVID-19 prevention recommendations. Harm reduction messaging around sharing of cannabis during surges of COVID-19 or other respiratory infections may provide benefit in reducing infection among those who use cannabis, especially as cannabis use in the USA continues to increase.

Trends in cannabis use among U.S. adults amid the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic has had an impact on mental health and alcohol use in the US, however there is little research on its impacts on cannabis use. Considering the role of cannabis as a coping strategy or self-medicating behavior, there is a need to understand how individuals who use cannabis have adapted their use amid the pandemic. Therefore, this study examined changes in self-reported cannabis use among US adults in the context of COVID-19 pandemic by (1) describing trends of use during the first 8 months of the pandemic among adults who used cannabis in this period; and (2) characterizing trends of use within sociodemographic subgroups and by state cannabis policy status. METHODS: The sample consisted of 1,761 US adults who used cannabis at least once during the 8-month study period from the nationally representative Understanding America Study. Linear mixed-effect models were used to model changes in the number of days of past-week cannabis use across 16 waves from March 10, 2020, to November 11, 2020. RESULTS: Compared to early March, the number of days cannabis was used per week was significantly higher at the start of April (ß=0.11, 95% CI=0.03, 0.18) and May (ß=0.21,95% CI=0.05, 0.36). In subsequent months (June - November), the number of days of cannabis use attenuated to levels comparable to March. Trends of cannabis use across the study period generally did not differ across sociodemographic characteristics and state cannabis policy status. CONCLUSION: Though increases in use were marginal among many groups, the evolving pandemic and the growing concern for the mental health of segments of the U.S. population warrant close monitoring of coping behaviors, including substance use.

Perceptions of and adherence to early COVID-19-related restrictions and associations with substance use among youth in Canada. / Perceptions et respect des premières restrictions liées à la COVID-19 et associations avec la consommation de substances chez les jeunes au Canada.

INTRODUCTION: As a largely social behaviour, substance use may have decreased for some youth overall in Canada during the COVID-19 pandemic; however, continued use may indicate nonadherence to pandemic-related restrictions and social distancing measures. In a sample of Canadian adolescents (aged 12-19 years), our objective was to examine how substance use (cannabis, binge drinking, cigarettes, vaping) is associated with perceptions of, and adherence to, early COVID-19-related public health measures, taking into consideration sociodemographic factors. METHODS: Cross-sectional data were retrieved from online data collected during Year 8 of the COMPASS school-based study, during the early months of the COVID-19 pandemic (May-July 2020) in British Columbia, Ontario and Quebec. We fitted two models using generalized estimating equations to examine how substance use was associated with separate measures of (1) perceptions of, and (2) adherence to early COVID-19 restrictions. RESULTS: In our sample, 10% of adolescents perceived COVID-19 restrictions as too weak and 14% perceived them as too strict. Nearly half (46%) reported taking restrictions very seriously, and 5% did not take them seriously at all. Binge drinking, cigarette use and vaping were associated with perceptions that restrictions were too strict and with nonadherence. However, adolescents who used cannabis were less likely to perceive COVID-19-related restrictions as too strict. CONCLUSION: This study highlights the association of adolescent substance use with perceptions of, and adherence to, COVID-19-related public health restrictions in Canada. Our findings emphasize a need for continual monitoring of substance use behaviours during the COVID-19 pandemic to better characterize adolescent risk and further inform targeted public health strategies accordingly.

The effect of recreational cannabis legalization on rates of traffic injury in Canada.

AIMS: To measure the impact of Canada's recreational cannabis legalization (RCL) in October 2018 and the subsequent impact of the coronavirus disease 2019 (COVID-19) lockdowns from March 2020 on rates of emergency department (ED) visits and hospitalizations for traffic injury. DESIGN: An interrupted time series analysis of rates of ED visits and hospitalizations in Canada recorded in population-based databases from January/April 2010 to March 2021. SETTING: ED visits in Ontario and Alberta and hospitalizations in Ontario, Alberta, British Columbia, the Prairies (Manitoba and Saskatchewan) and the Maritimes (Nova Scotia, New Brunswick, Newfoundland and Prince Edward Island). PARTICIPANTS: Monthly counts of presentations to the ED or hospital for motor vehicle injury or pedestrian/cyclist injury, used to calculate monthly rates per 100 000 population. MEASUREMENTS: An occurrence of one or more International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Canada (ICD-10-CA) code for motor vehicle injury (V20-V29, V40-V79, V30-V39 and V86) and pedestrian/cyclist injury (V01-V09 and V10-V19) within the National Ambulatory Care Reporting System and Discharge Abstract Database. FINDINGS: There were no statistically significant changes in rates of ED visits and hospitalizations for motor vehicle or pedestrian/cyclist injury after RCL after accounting for multiple testing. After COVID-19, there was an immediate decrease in the rate of ED visits for motor vehicle injury that was statistically significant only in Ontario (level change ß = -16.07 in Ontario, 95% CI = -20.55 to -11.60, P = 0.000; ß = -10.34 in Alberta, 95% CI = -17.80 to -2.89, P = 0.008; α of 0.004) and no changes in rates of hospitalizations. CONCLUSIONS: Canada's recreational cannabis legalization did not notably impact motor vehicle and pedestrian/cyclist injury. The rate of emergency department visits for motor vehicle injury decreased immediately after COVID-19 lockdowns, resulting in rates below post-recreational cannabis legalization levels in the year after COVID-19.