Cannabis Use and Health-Related "Harm to Others": Toward a Conceptual Framework and Evidence Base for Public Health.

Cannabis use has become increasingly common as more jurisdictions liberalize controls, including legalization and allowing nonmedical cannabis use among adults, to better protect public health and safety. Little attention has been given to possible health-related "harm to others," as are considered in other substance use domains. We propose a framework and review evidence on public health domains in which cannabis use may produce health-related harm to others, namely from (a) interpersonal violence, (b) motor vehicle crash-related injuries, (c) pregnancy-related outcomes, and (d) secondhand exposure. These domains are associated with moderate risks of adverse outcomes that, however, may involve substantial health harm to others, and therefore warrant consideration in guiding regulations and in evaluating the public health impacts of cannabis use and different policy options for its control.

Cannabis use, risk behaviours and harms in Brazil: A comprehensive review of available data indicators.

ISSUES: Cannabis use and related health/social outcome indicator data for Brazil-where non-medical cannabis is generally illegal-are limited. APPROACH: Towards a comprehensive overview of relevant indicators, we searched primary databases by combining MeSH-index terms related to cannabis, geographic location and subtopic terms (e.g., use, health, mortality) focusing on cannabis use and key outcome indicators in Brazil since 2010. In addition, relevant 'grey literature' (e.g., survey reports) was identified. Key indicator data were mainly narratively summarised. KEY FINDINGS: Overall, cannabis use has increased somewhat since pre-2010, with (past-year) use rates measured at 2-3% for general population adults, yet 5% or higher among youth and/or (e.g., post-secondary) student populations. For key risk behaviours, the presence of tetrahydrocannabinol-positivity among motor-vehicle drivers has been measured at <2%. While the prevalence of cannabis use disorder appears to have decreased, the relative proportion of treatment provided for cannabis-related problems increased. National- and local-based studies indicated an association of cannabis use with mental health harms, including depression and suicidality. Although some non-representative and/or local studies contain information, other monitoring data, including cannabis-related risks and harms (e.g., cannabis-related driving, mortality, hospitalisations), are limited in availability. IMPLICATIONS AND CONCLUSION: The prevalence of cannabis use in Brazil is comparably low (e.g., relative to elsewhere in the Americas). Data on numerous key cannabis-related indicators is absent, or limited in scope for Brazil. Considering ongoing evolutions in cannabis control and its status as the most common illicit drug, more comprehensive surveillance of cannabis use and related outcomes is advised.

Lower-Risk Cannabis Use Guidelines (LRCUG) for reducing health harms from non-medical cannabis use: A comprehensive evidence and recommendations update.

BACKGROUND: Cannabis use is common, especially among young people, and is associated with risks for various health harms. Some jurisdictions have recently moved to legalization/regulation pursuing public health goals. Evidence-based 'Lower Risk Cannabis Use Guidelines' (LRCUG) and recommendations were previously developed to reduce modifiable risk factors of cannabis-related adverse health outcomes; related evidence has evolved substantially since. We aimed to review new scientific evidence and to develop comprehensively up-to-date LRCUG, including their recommendations, on this evidence basis. METHODS: Targeted searches for literature (since 2016) on main risk factors for cannabis-related adverse health outcomes modifiable by the user-individual were conducted. Topical areas were informed by previous LRCUG content and expanded upon current evidence. Searches preferentially focused on systematic reviews, supplemented by key individual studies. The review results were evidence-graded, topically organized and narratively summarized; recommendations were developed through an iterative scientific expert consensus development process. RESULTS: A substantial body of modifiable risk factors for cannabis use-related health harms were identified with varying evidence quality. Twelve substantive recommendation clusters and three precautionary statements were developed. In general, current evidence suggests that individuals can substantially reduce their risk for adverse health outcomes if they delay the onset of cannabis use until after adolescence, avoid the use of high-potency (THC) cannabis products and high-frequency/-intensity of use, and refrain from smoking-routes for administration. While young people are particularly vulnerable to cannabis-related harms, other sub-groups (e.g., pregnant women, drivers, older adults, those with co-morbidities) are advised to exercise particular caution with use-related risks. Legal/regulated cannabis products should be used where possible. CONCLUSIONS: Cannabis use can result in adverse health outcomes, mostly among sub-groups with higher-risk use. Reducing the risk factors identified can help to reduce health harms from use. The LRCUG offer one targeted intervention component within a comprehensive public health approach for cannabis use. They require effective audience-tailoring and dissemination, regular updating as new evidence become available, and should be evaluated for their impact.

Developments and Changes in Primary Public Health Outcome Indicators Associated with the Legalization of Non-Medical Cannabis Use and Supply in Canada (2018): A Comprehensive Overview.

Canada legalized non-medical cannabis use and supply for adults in 2018. We examined developments and changes associated with the legalization policy reform on key indicators for public health, namely cannabis (including frequent/problematic) use prevalence, cannabis-related hospitalizations, cannabis-impaired driving, and cannabis sourcing. We identified peer-reviewed and "grey" study data that featured population-level or other quasi-representative samples and comparable outcome data for pre- and post-legalization periods, including possible trends of changes over time. Cannabis use has increased in select population groups, with use modes shifting away from smoking. Evidence on cannabis-related hospitalizations (e.g., for mental health) is mixed. The prevalence of cannabis-impaired driving appears to be generally steady but THC exposure among crash-involved drivers may have increased. Increasing proportions of users obtain cannabis products from legal sources but some-especially regular-users continue to use illicit sources. Overall, data suggest a mixed and inconclusive picture on cannabis legalization's impacts on essential public health indicators, including select extensions in trends from pre-legalization.

An overview of select cannabis use and supply indicators pre- and post-legalization in Canada.

BACKGROUND: Canada implemented the legalization and regulation of non-medical cannabis use, production and sale in 2018 aiming to improve public health and safety. While outcomes from legalization reforms in other jurisdictions mostly rely on US-based data have been assessed to be mixed, Canadian data are only emerging. We compiled select population-level data on key indicators to gauge initial developments from pre- to post-legalization of cannabis in Canada. METHODS: We examined indicators data focusing on the following topics: prevalence of cannabis use, frequency of use, methods/products of consumption, driving after cannabis use, and cannabis sourcing. Indicator data were obtained mostly from national and some provincial population surveys. Prevalence or percentages for the indicators pre- and post-legalization (e.g., 2017- 2020), including confidence intervals were reported, with changes noted, as available in and indicated by the data sources. RESULTS: Data suggested selected increases in cannabis use prevalence, mostly among mid- and older- but possibly also younger (e.g., under legal use age) users. Frequency of use and driving after cannabis use among active users do not appear to have changed. Methods of cannabis use show diversifying trends, with decreases in smoking and increases in alternatives use modes (e.g., edibles, vaping). There is a clearly increasing trend towards accessing cannabis from legal sources among adults, while under-legal-use-age youth do not appear to experience heightened barriers to obtaining cannabis in legalization contexts. CONCLUSIONS: Preliminary indicators on cannabis legalization in Canada show a mixed picture, some similar to US-based developments. While some use increases are observed, these do not necessarily represent indications of increases in cannabis-related harm, also since key (e.g., hospitalization or injury) data are lacking to date. There is a gradual embracing of legal supply sources of cannabis among users, which can be expected to serve public health and safety objectives. At the same time, cannabis use and access among under-age users as a principally vulnerable group do not appear to be hindered or reduced by legalization.

Factors associated with crack-cocaine early initiation: a Brazilian multicenter study.

BACKGROUND: Crack-cocaine dependence is a serious public health issue, related to several psychiatric and psychosocial problems. Crack-cocaine users are usually embedded in a context of great social vulnerability, often associated with violence, poverty, family conflict and easy and early access to alcohol, tobacco and other drugs. METHODS: This cross-sectional study enrolled a consecutive sample of 577 patients admitted to 20 therapeutic communities located in Southern Brazil, between September 2012 and September 2013. A structured interview assessed life-time exposure to risk and protective factors for drug use, such as parental monitoring in childhood, deviant behaviors and peer pressure. RESULTS: Presence of family conflict (p = 0.002), maltreatment (p = 0.016), and deviant behavior prior to age 15 in a bivariate analysis predicted an earlier age of crack-cocaine initiation, whereas adolescents experiencing parental monitoring during adolescence started use later (p < 0.001). In the multivariate model, perceptions related to ease of access of illicit drugs (marijuana: p = 0.028, 95% CI = - 3.81, - 0.22; crack-cocaine: p < 0.001, 95% CI = - 7.40, - 4.90), and deviant behavior (threatening someone with a gun: p = 0.028, 95% CI = - 2.57, - 0.14) remained independent predictors of early age of crack-cocaine initiation. CONCLUSIONS: Early onset of crack-cocaine use seems to be associated with exposure to family conflict, easy access to drugs and deviant behavior. Treatment and preventive programs should take these factors into account when designing and implementing community interventions.

Oral HPV among people who use crack-cocaine: prevalence, genotypes, risk factors, and key interventions in a remote Northern Brazilian region.

OBJECTIVES: This study estimated the prevalence, genotype distribution, and the factors associated with oral human papillomavirus (HPV) in people who use crack-cocaine (PWUCC) in a remote Brazilian region. MATERIALS AND METHODS: This cross-sectional study used community-based snowball sampling methods for participant recruitment. Socio-demographic, economic, drug use, and health-related information was collected from 278 PWUCC in the cities of Bragança and Capanema in northern Brazil. HPV diagnosis and genotyping were performed by a real-time polymerase chain reaction. Logistic regression identified the factors independently associated with oral HPV. RESULTS: In total, 111 (39.9%) PWUCC had HPV DNA. Several genotypes were identified, some of them with high oncogenic potential. Crack-cocaine use ≥40 months, unprotected sex, more than 10 sexual partners in the last 12 months, oral sex, exchange of sex for money or illicit drugs, oral mucosa lesions, not having access to public health services, and the absence of vaccination against HPV was all associated with HPV DNA. CONCLUSIONS: This study identified important epidemiological characteristics of oral HPV infection among PWUCC-a highly marginalized risk population-underlining the high prevalence of oral HPV with oncogenic potential and the urgent need for control and prevention measures, especially vaccination against this virus. CLINICAL RELEVANCE: It is necessary to understand the prevalence and risk factors of oral HPV in risk populations as people who use crack-cocaine.

Lower-Risk Cannabis Use Guidelines: Adherence in Canada and the U.S.

INTRODUCTION: This study examines the prevalence of risky cannabis use based on adherence to the Lower-Risk Cannabis Use Guidelines. METHODS: Respondents aged 16-65 years in Canada and the U.S. (N=27,024) completed the online 2018 International Cannabis Policy Study. Participants completed measures corresponding to the Lower-Risk Cannabis Use Guidelines and Alcohol, Smoking and Substance Involvement Screening Test. Analyses were conducted in 2019. RESULTS: More than half of the respondents (57.3%, n=15,489) had ever used cannabis, and 28.1% (n=7,584) had used it in the past 12 months (current use). The majority of current consumers (88.8%) reported nonadherence to ≥1 guideline other than ever use. These behaviors included smoking ≥50% of all cannabis consumed (69.8%), using high-tetrahydrocannabinol products (44.9%), initiating cannabis use before age 16 years (35.9%), daily/near-daily use (32.2%), driving after cannabis use (26.1%), cannabis use during pregnancy or with a history of psychosis or substance abuse (17.3%), and synthetic cannabis use (5.9%). More respondents in U.S. legal recreational cannabis states reported nonadherence than those in jurisdictions where recreational cannabis remained illegal. Specifically, consumers in U.S. legal states were significantly more likely to use high-tetrahydrocannabinol products than consumers in U.S. illegal states or Canada and more likely to drive after cannabis use than consumers in Canada (p<0.001 for all). Adherence to Lower-Risk Cannabis Use Guidelines was strongly associated with Alcohol, Smoking and Substance Involvement Screening Test scores. CONCLUSIONS: Lower-Risk Cannabis Use Guideline adherence differed by jurisdiction and sociodemographic profile. As more jurisdictions legalize nonmedical cannabis, targeted interventions for key risk behaviors (e.g., using high-potency cannabis, early initiation age, driving after cannabis use) are warranted.

Evaluating the intended and unintended consequences of opioid-prescribing interventions on primary care in British Columbia, Canada: protocol for a retrospective population-based cohort study.

INTRODUCTION: Between 2015 and 2018, there were over 40 000 opioid-related overdose events and 4551 deaths among residents in British Columbia (BC). During this time the province mobilised a variety of policy levers to encourage physicians to expand access to opioid agonist treatment and the College of Physicians and Surgeons of British Columbia (CPSBC) released a practice standard establishing legally enforceable minimum thresholds of professional behaviour in the hopes of curtailing overdose events. Our goal is to conduct a comprehensive investigation of the intended and unintended consequences of these policy changes. Specifically, we aim to understand the effects of these measures on physician prescribing behaviours, identify physician characteristics associated with uptake of the new measures, and measure the effects of the policy changes on patients' access to quality primary care. METHODS AND ANALYSIS: This is a population-level, retrospective cohort study of all BC primary care physicians who prescribed any opioid medication for opioid-use disorder or chronic non-cancer pain during the study period, and their patients. The study period is 1 January 2013-31 December 2018, with a 1-year wash-in period (1 January 2012-31 December 2012) to exclude patients who initiated long-term opioid treatment prior to our study period or whose pain type (ie, 'chronic non-cancer', 'acute', 'cancer or palliative', or 'other') cannot be confirmed. The project combines five administrative health datasets under the authority of the BC Ministry of Health, with the CPSBC's Physician Registry, BC Cancer Agency's Cancer Registry and Vital Statistics' Mortality data. We will create measures of prescribing concordance, access, continuity, and comprehensiveness to assess primary care delivery and quality at both the physician and patient level. We will use generalised estimating equations, interrupted time series, mixed effects models, and funnel plots to identify factors related to changes in prescribing and evaluate the impact of the changes to prescribing policies. Results will be reported using appropriate Enhancing the QUAlity and Transparency Of health Research guidelines (eg, STrengthening the Reporting of OBservational studies in Epidemiology). ETHICS AND DISSEMINATION: This study has been approved by McGill University's Institutional Review Board (#A11-M55-19A), and the University of British Columbia's Research Ethics Board (#H19-03537). We will disseminate results via a combination of open access peer-reviewed journal publications, conferences, lay summaries and OpEds.

The Lower-Risk Cannabis Use Guidelines' (LRCUG) recommendations: How are Canadian cannabis users complying?

Canada, alongside other jurisdictions, implemented non-medical cannabis legalization in 2018, partly towards improving public health. Evidence-based 'Lower-Risk Cannabis Use Guidelines' (LRCUG), including recommendations for cannabis users on how to decrease risk-behaviors for harms, have been developed and widely disseminated in Canada since 2017. However, knowledge on users' compliance with the LRCUG is limited. We identified four major Canadian (three national, one provincial) population surveys presenting key data on cannabis-related behaviors: the National Cannabis Survey, Canadian Cannabis Survey, Canadian Tobacco, Alcohol & Drugs Survey, and CAMH Monitor. We scanned each survey for indicator data mapping onto either of the LRCUG's recommendations for the years 2017 to 2019. Relevant indicator data, albeit with varying operationalizations, were found for six of the ten LRCUG's recommendation clusters in at least some of the surveys, and were extracted and summarized. For results, substantial -- but declining -- majorities of users consumed cannabis by smoking, yet with shifts towards other use modes. Between one- to two-in-five users engaged in the risk-behaviors of using high-potency cannabis products, frequent cannabis use and cannabis-impaired driving, respectively. A small proportion of pregnant or breastfeeding women continued cannabis use during the study period. The data identified found suggested a heterogeneous picture regarding cannabis users' compliance with the LRCUG's recommendations. Non-compliance is highest for recommendations regarding modes-of-use, and applies to minorities of users for other risks factors. These sub-groups are at elevated risk for acute (e.g., accidents) or long-term (e.g., dependence) cannabis-related harms contributing to the public health burden. Appropriate targeted interventions in these areas require improvement.

Emerging prospects for non-medical cannabis legalisation in New Zealand: An initial view and contextualization.

New Zealand may be the next national jurisdiction where non-medical cannabis use and supply will be legalized. While the current New Zealand government's plans for possible cannabis legalization were rather unclear for some time, initial details on proposed key parameters (for example, age limits, production and supply modes, use restrictions) of a possible cannabis legalization framework have recently emerged. We provide initial basic examination and contextualization of the proposal's select key details, both vis-a-vis select legalization frameworks as they exist in other jurisdictions as well as in reference to key parameters of policy and controls governing other legal psychoactive substances in New Zealand. Overall, the proposed framework for non-medical cannabis legalization in New Zealand resembles other (e.g., Canada's) legalization models in spirit and main proposed regulations. There are, however, several proposed regulation elements where questions regarding both feasibility and/or policy coherence concerning other psychoactive substance areas arise and likely to lead to challenges or problems in practice. Evidently, substantially more thinking, consideration and development need to be invested towards a more complete and workable public health-oriented framework and roadmap for cannabis legalization in New Zealand. Furthermore, possible cannabis legalization reforms hinge on the successful outcome of a public referendum (in late 2020), adding the acute need for substantive pre-referendum public education as well as overall extrinsic uncertainty regarding the prospects of actual and material policy change.

Introducing the evidence-based population health tool of the Lower-Risk Cannabis Use Guidelines to Brazil

Cannabis is the most commonly used illegal drug, and is associated with well-documented adverse health outcomes, both acute and chronic. Cannabis use prevalence in Brazil is lower than in high-use regions in the Americas (e.g., North America), but concentrated among young people. Frameworks for cannabis control are increasingly shifting towards public health-oriented principles, with some countries undertaking respective policy reforms. These frameworks require a continuum of population-level interventions (e.g., prevention and treatment) including targeted prevention of adverse health outcomes among users. In this context, and based on examples from other health fields, an international expert group developed the evidence-based Lower-Risk Cannabis Use Guidelines (LRCUG), originally for Canada, including a set of 10 recommendations based on systematic data reviews and expert consensus methods. The LRCUG form a scientific population-health prevention tool to reduce adverse public health impacts for broad application among cannabis users. In Canada, the LRCUG have been formally endorsed and are supported by leading national health organizations and government authorities within the continuum of cannabis interventions. As the LRCUG are being internationalized, this paper introduces the LRCUG's concept and content - including their original recommendations translated into Portuguese - to the Brazilian context as an evidence-based population-level intervention tool for uptake, dissemination, and discussion. Sociocultural adaptation may be required for meaningful implementation.

Human T-lymphotropic virus 1 and 2 among people who used illicit drugs in the state of Pará, northern Brazil.

People who used illicit drugs (PWUDs) represent an important population group for acquisition and viral dispersion. In Brazil, high rates of the human T lymphotropic virus 1 (HTLV-1) and 2 (HTLV-2) have been reported in epidemiological studies. However, the epidemiological scenario of HTLV-1/2 infections in PWUDs is still poorly understood. Thus, this cross-sectional study determined the prevalence, frequency of subtypes and factors associated with HTLV-1/2 infections among PWUDs in the Brazilian state of Pará, an area considered endemic for this virus and with poor health services. Among 826 PWUDs, 53 (6.4%) presented anti-HTLV-1/2 antibodies by EIA and 44 (5.3%) presented proviral DNA by PCR. HTLV-1 and HTLV-2 were detected in 25 (3.0%) and 19 (2.3%) PWUDs, respectively. Subtypes 1a (25/44), transcontinental (23/44) and Japanese subgroups (2/44), 2b (6/44) and 2c (13/44) were identified. Involvement in illicit/criminal activity, daily use of illicit drugs, illicit drug use over 12 years, unprotected sex with other PWUDs, changes in genitalia (including ulcers and wounds), and more than 12 sexual partners were associated with HTLV-1/2 in PWUDs. This high prevalence and intense circulation of subtypes and subgroups of HTLV-1/2 is very worrying, and indicate the need for urgent actions for its control, prevention and treatment.

Guidelines for public health and safety metrics to evaluate the potential harms and benefits of cannabis regulation in Canada.

ISSUES: Canada recently introduced a public health-based regulatory framework for non-medical cannabis. This review sought to identify a comprehensive set of indicators to evaluate the public health and safety impact of cannabis regulation in Canada, and to explore the ways in which these indicators may be expected to change in the era of legal non-medical cannabis. APPROACH: Five scientific databases were searched to compile a list of cannabis-related issues of interest to public health and safety. A set of indicators was developed based on topics and themes that emerged. Preliminary evidence from other jurisdictions in the USA and Canada that have legalised medical and/or non-medical cannabis (e.g. Colorado, Washington) was summarised for each indicator, wherever possible. KEY FINDINGS: In total, 28 indicators were identified under five broad themes: public safety; cannabis use trends; other substance use trends; cardiovascular and respiratory health; and mental health and cognition. Preliminary trends from other legalised jurisdictions reveal little consensus regarding the effect of cannabis legalisation on public health and safety harms and an emerging body of evidence to support potential benefits (e.g. reductions in opioid use and overdose). IMPLICATIONS: In addition to indicators of commonly discussed challenges (e.g. cannabis-related hospitalisations, cannabis-impaired driving), this review led to the recommendation of several indicators to monitor for possible public health and safety improvements. CONCLUSION: In preparing a comprehensive public health and safety monitoring and evaluation system for cannabis regulation, this review underscores the importance of not only measuring the possible risks but also the potential benefits.

Assessing the public health impact of cannabis legalization in Canada: core outcome indicators towards an 'index' for monitoring and evaluation.

The legalization of non-medical cannabis use and supply is impending in Canada. This constitutes a major policy change with the declared objective of improving public health outcomes, which requires rigorous monitoring and evaluation. While numerous different aspects associated with legalization will be examined, a focused perspective is required for effective policy evaluation purposes. To these ends, we have identified a set of 10 core indicators associated with cannabis-related risk/harm outcomes-based on current best evidence-that are expected to measure the primary impacts of legalization on public health outcomes. We briefly review these indicators, and their respective data availability in Canada. As ideally an integrated outcome assessment of cannabis legalization's impact on public health will be available, we further propose options to merge the individual indicators into an integrated, weighted 'index', considering their expected relative impact for public health. One possible approach to undertake this is 'multi-criteria decision analysis' as a method to weight the relative indicator impact on public health; alternative approaches are proposed. The integrated 'public health index' for cannabis legalization will allow for scientifically comprehensive, while focused, monitoring and evaluation of the effects of legalization in Canada for the benefits of science and evidence-based policy alike.

Routes of administration for cannabis use - basic prevalence and related health outcomes: A scoping review and synthesis.

BACKGROUND: Cannabis use is common, and associated with adverse health outcomes. 'Routes of administration' (ROAs) for cannabis use have increasingly diversified, in part influenced by developments towards legalization. This paper sought to review data on prevalence and health outcomes associated with different ROAs. METHODS: This scoping review followed a structured approach. Electronic searches for English-language peer-reviewed publications were conducted in primary databases (i.e., MEDLINE, EMBASE, PsycINFO, Google Scholar) based on pertinent keywords. Studies were included if they contained information on prevalence and/or health outcomes related to cannabis use ROAs. Relevant data were screened, extracted and narratively summarized under distinct ROA categories. RESULTS: Overall, there is a paucity of rigorous and high-quality data on health outcomes from cannabis ROAs, especially in direct and quantifiable comparison. Most data exist on smoking combusted cannabis, which is associated with various adverse respiratory system outcomes (e.g., bronchitis, lung function). Vaporizing natural cannabis and ingesting edibles appear to reduce respiratory system problems, but may come with other risks (e.g., delayed impairment, use 'normalization'). Vaporizing cannabis concentrates can result in distinct acute risks (e.g., excessive impairment, injuries). Other ROAs are uncommon and under-researched. CONCLUSIONS: ROAs appear to distinctly influence health outcomes from cannabis use, yet systematic data for comparative assessments are largely lacking; these evidence gaps require filling. Especially in emerging legalization regimes, ROAs should be subject to evidence-based regulation towards improved public health outcomes. Concretely, vaporizers and edibles may offer potential for reduced health risks, especially concerning respiratory problems. Adequate cannabis product regulation (e.g., purity, labeling, THC-restrictions) is required to complement ROA-based effects.

Hepatitis C virus infection among illicit drug users in an archipelago of the Amazon.

Hepatitis C virus (HCV) infection causes acute and chronic liver disease and may lead to cirrhosis, liver failure or hepatocellular carcinoma. The behavior of illicit drug users (DUs) typically exposes them to risks of viral infection. In the Brazilian Amazon region, a number of studies have identified high rates of drug use among adolescents, and a high prevalence of HBV infection in DUs, disseminated by sexual and parenteral activities. However, the epidemiological scenario of HCV infection in the region is still poorly understood. This study determined the prevalence, genotypes, and risk factors for HCV infection among DUs of the Marajó Archipelago. This cross-sectional study collected samples and epidemiological information from DUs in 11 municipalities. The diagnosis was established by EIA and real-time PCR, and the samples were genotyped by multiplex real time PCR. The data were analyzed by simple and multiple logistical regression. In 466 DUs, 28.3% had anti-HCV antibodies, and 25.5% had HCV-RNA. In 92 injecting drug users, 88.0% had anti-HCV antibodies, and 80.4% had HCV-RNA. Genotypes 1 and 3 were detected, with three cases of mixed infections. The multivariate analysis indicated associations of HCV infection with age (≥ 35 years), tattoos, intravenous drug use, shared use of injection equipment, and the daily and long-term (> 3 years) use of illicit drugs. These findings will contribute to the development of effective measures for the prevention of HCV infection among Brazilian DUs, as well as its general population.

The Devil Is in the Details! On Regulating Cannabis Use in Canada Based on Public Health Criteria Comment on "Legalizing and Regulating Marijuana in Canada: Review of Potential Economic, Social, and Health Impacts".

This commentary to the editorial of Hajizadeh argues that the economic, social and health consequences of legalizing cannabis in Canada will depend in large part on the exact stipulations (mainly from the federal government) and on the implementation, regulation and practice of the legalization act (on provincial and municipal levels). A strict regulatory framework is necessary to minimize the health burden attributable to cannabis use. This includes prominently control of production and sale of the legal cannabis including control of price and content with ban of marketing and advertisement. Regulation of medical marijuana should be part of such a framework as well.

Comparing Medical and Recreational Cannabis Users on Socio-Demographic, Substance and Medication Use, and Health and Disability Characteristics.

BACKGROUND: While recreational cannabis use is common, medical cannabis programs have proliferated across North America, including a federal program in Canada. Few comparisons of medical and recreational cannabis users (RCUs) exist; this study compared these groups on key characteristics. METHODS: Data came from a community-recruited sample of formally approved medical cannabis users (MCUs; n = 53), and a sub-sample of recreational cannabis users (RCUs; n = 169) from a representative adult survey in Ontario (Canada). Samples were telephone-surveyed on identical measures, including select socio-demographic, substance and medication use, and health and disability measures. Based on initial bivariate comparisons, multivariate logistical regression with a progressive adjustment approach was performed to assess independent predictors of group status. RESULTS: In bivariate analyses, older age, lower household income, lower alcohol use, higher cocaine, prescription opioid, depression and anxiety medication use, and lower health and disability status were significantly associated with medical cannabis use. In the multivariate analysis, final model, household income, alcohol use, and disability levels were associated with medical cannabis use. Conclusions/Scientific Significance: Compared to RCUs, medical users appear to be mainly characterized by factors negatively influencing their overall health status. Future studies should investigate the actual impact and net benefits of medical cannabis use on these health problems.