Building the data infrastructure to evaluate cannabis legalization

A Systematic Review of Trends in US Attitudes toward Cannabis Legalization

METHODS

A systematic search was conducted for publications in PubMed, EMBASE, and PsycINFO up to October 2019. Six studies with a regionally or nationally representative adult US-based populations were included. A secondary analysis was conducted using data from the National Survey of Drug Use and Health. Hierarchical age-period-cohort analysis assessed the trends in perceived harmfulness and availability of cannabis between 1996 and 2018. Ecological comparisons were made between these perceptions and support for cannabis legalization over time.

RESULTS

A steep growth in support for cannabis legalization began in the 1990s and continued to grow in a relatively linear manner. Most people developed more liberal views, with no evidence that changes within any one sociodemographic group was disproportionately responsible for the overall attitudinal change. Increases in the proportion of people who use cannabis, non-religious population and political liberalism may partially explain the increased support for legalization. The decline in perceived harmfulness of cannabis, as reflected in the media, may have contributed to the increased support for legalization. However, perceptions of the availability of cannabis remained stable despite significant relaxations in cannabis regulations.

CONCLUSIONS

The US population has become more accepting of cannabis legalization. The attitudinal change is related to changes in the perceived risks and benefits of cannabis use, influenced by broader political and cultural changes over the study period.

Public health implications of legalising the production and sale of cannabis for medicinal and recreational use

We assess the current and describe possible future public health impacts of the legalisation of cannabis production, sale, and use in the Americas. First, we describe global patterns of cannabis use and their most probable adverse health effects. Second, we summarise evidence regarding the effectiveness of cannabinoids for medicinal use and describe approaches that have been used to regulate the use of medicinal cannabis and how these approaches might have affected medicinal and recreational use and harms (eg, road crashes). Third, we describe how jurisdictions that have legalised recreational use have regulated production and sale of cannabis. Fourth, we evaluate the effects of cannabis legalisation on cannabis use and harms and on the use of alcohol, tobacco, and other drugs. Fifth, we use alcohol and tobacco policy examples to identify possible long-term public health effects of cannabis legalisation. Finally, we outline policy approaches that could minimise harms to public health arising from the legalisation of a commercial cannabis industry.

Cannabis use in Switzerland 2015-2045: A population survey based model

BACKGROUND

Alternative cannabis regulation models are discussed and implemented worldwide. A baseline scenario under the assumption of no policy or market changes may prove useful to forecast cannabis use and treatment demand and evaluate changes in legislation.

METHODS

Based on data of the Continuous Rolling Survey of Addictive Behaviours and Related Risks on cannabis use, age, gender and nationality from 2011 to 2015, we used general estimating equation analysis to model lifetime and 30-days prevalence from 2015 to 2045 in Switzerland accounting for demographic trends.

RESULTS

Lifetime prevalence of cannabis use is projected to grow from 28.3% (CI 95% 27.8-28.8) in 2015 to 42.0% (CI 95% 41.0-43.0) in 2045. 30-days prevalence would increase slightly from 2.70% (CI 95% 2.53-2.88) to 3.39% (CI 95% 3.11-3.66). Due to population growth, absolute numbers with past 30-day cannabis use are estimated to increase from 202,784 (CI 95% 189,534-216,035) to 314,302 (CI 95% 288,504-340,100). Among those aged under 30 years no substantial change in lifetime and 30-days prevalence of cannabis use is projected. Larger changes are estimated to occur in the age group 30+. The mean age of past 30-day cannabis users would increase for men with Swiss nationality from 30.3 to 38.7 years.

DISCUSSION

Population-based survey data and demographic projections can be used to develop baseline scenarios of future cannabis use. Assuming no changes in cannabis legislation, growing absolute numbers of users will likely increase treatment demand. Cannabis use is estimated to increase among the group aged >30 years, which is currently underrepresented in clinical treatment and research. Our findings highlight the need for prospective baseline scenarios to evaluate the impact of legislative changes on cannabis use. Moreover, in Switzerland effective prevention and treatment interventions for cannabis use disorders are required even if cannabis legislation remains unchanged.

Co-use of cannabis, tobacco, and alcohol during adolescence: policy and regulatory implications

Legislative reforms have legalized use of cannabis for medical and recreational purposes. Efforts to evaluate the public health impact of these changes have predominantly focused on determining whether liberalizing cannabis policies has increased cannabis use patterns. Co-use of cannabis and other licit substances, namely tobacco and alcohol, is common during the developmental period of adolescence, which is generally characterized by an increase in risk-taking and novelty-seeking. However, limited research has sought to evaluate the potential implications of reforms to medical and recreational cannabis laws on concurrent and simultaneous use of cannabis, tobacco, and alcohol during adolescence. The current report reviews the extant literature detailing the prevalence and outcomes associated with concurrent and simultaneous cannabis-tobacco and cannabis-alcohol use, including recent work that has examined how concurrent and simultaneous use may be influenced by cannabis reform. This review details how the cannabis landscape and cannabis retail marketplace have evolved and briefly summarizes the corresponding policy and regulatory challenges that have emerged. The report concludes with a focused cannabis co-use research agenda that adopts different strategies including behavioural economic, self-administration, and survey research methods.

Cannabis regulatory science: risk-benefit considerations for mental disorders

The evolving legal cannabis landscape in the US continues to present novel regulatory challenges that necessitate the development of a Cannabis Regulatory Science. Two specific issues of concern within Cannabis Regulatory Science are (1) the impact that cannabis use has on the incidence, prevalence, and severity of mental disorders, and (2) how cannabis laws and regulations modify this impact. This paper first provides several conceptual points that are useful for evaluating the relationship between cannabis use and mental disorders. Second, it selectively reviews and comments on data relevant to the relationship between cannabis use and depression, several forms of anxiety, post-traumatic stress disorder, schizophrenia, and bipolar disorder. Next, regulatory and public health parallels between the nascent cannabis industry and the pharmaceutical, tobacco, and alcohol industries are discussed. The focus is on specific types of industry practices that may harm those with or at risk for mental disorders. Recommendations are then offered for legal cannabis regulations that could mitigate this harm. Last, future research goals are discussed for building the field of Cannabis Regulatory Science and addressing the potential negative impact of cannabis on those with mental disorders.

Studying Cannabis Use Behaviors With Facebook and Web Surveys: Methods and Insights

The rapid and wide-reaching expansion of internet access and digital technologies offers epidemiologists numerous opportunities to study health behaviors. One particularly promising new data collection strategy is the use of Facebook’s advertising platform in conjunction with Web-based surveys. Our research team at the Center for Technology and Behavioral Health has used this quick and cost-efficient method to recruit large samples and address unique scientific questions related to cannabis use. In conducting this research, we have gleaned several insights for using this sampling method effectively and have begun to document the characteristics of the resulting data. We believe this information could be useful to other researchers attempting to study cannabis use or, potentially, other health behaviors. The first aim of this paper is to describe case examples of procedures for using Facebook as a survey sampling method for studying cannabis use. We then present several distinctive features of the data produced using this method. Finally, we discuss the utility of this sampling method for addressing specific types of epidemiological research questions. Overall, we believe that sampling with Facebook advertisements and Web surveys is best conceptualized as a targeted, nonprobability-based method for oversampling cannabis users across the United States.