How ideology shapes the evidence and the policy: what do we know about cannabis use and what should we do?

Beliefs about cannabis at the time of legalization in Canada: results from a general population survey

Aims

Cannabis became a legally available drug in Canada in October of 2018. The objective of this study was to examine beliefs about cannabis use at the time of legalization among past year cannabis users, those who had used cannabis but not in the last year, and people who had never used cannabis.

Design and methods

A survey of 813 participants, 18 years and over, and identified using random digit dialing methods, was made of the Canadian general population. Among other items, participants were asked a series of questions about their beliefs regarding cannabis use and recovery.

Results

Compared to never and ever users, participants who used cannabis in the last year regarded cannabis as less of a societal problem (mean [SD] past year use = 3.8 [2.4] versus 6.4 [2.6] and 6.0 [2.4] respectively, p = .001), than people were less likely to become addicted to cannabis if they tried it (past year use = 13.3% versus 48.3% and 25.1%, p = .001), and a larger proportion believed that recovery from cannabis without treatment was likely (past year use = 40.8% versus 14.2% and 19.3%, p = .001). All groups were equally positive of the chances of recovering from cannabis addiction with treatment (p = .72).

Discussion and conclusion

Beliefs about cannabis use vary substantially between those who have used the drug in the past year and those who have not. Replication of the survey at a later date is merited in order to assess the ways in which beliefs about cannabis evolve after an extended period of cannabis being available as a legal drug.

Police crackdowns, structural violence and impact on the well-being of street cannabis users in a Nigerian city

BACKGROUND

There is abundant literature on the impact of law enforcement on cannabis markets, but scant literature on the effects of law enforcement on cannabis users. This study undertook a qualitative exploration of police crackdowns as a form of structural violence and examined their impact on the well-being of street cannabis users in a Nigerian city.

METHODS

The study was qualitative and descriptive. It was carried out in Uyo, southern Nigeria. Ninety-seven (97) frequent cannabis users (78 males and 19 females) took part. They were aged between 21 and 34 years and recruited from 11 cannabis hot-points in the city. Data were collected through in-depth, individual interviews, conducted over six-months. Data analysis was thematic and data-driven, involving identifying themes, assigning codes, revising codes and verification by independent qualitative methodology experts.

RESULTS

Police crackdowns are commonly experienced by street cannabis users. These do not reduce cannabis use, but displace cannabis markets. Crackdowns are associated with police brutality, confiscation of funds, drugs and belongings, stigma and discrimination, arrest and incarceration, which impacts negatively on the health, livelihoods and well-being of cannabis users. Cannabis users try to escape arrest by running from police, disposing of cannabis, disguising themselves and, when caught, bribing officers to secure release.

CONCLUSION

Crackdowns constitute a form of structural violence in the everyday life of cannabis users, and have negative effects on their health and social and economic well-being. Cannabis use should be decriminalized de facto and arrested users directed to treatment and skills training programmes. Treatment and social services for users should be expanded and legal aid interventions should be mounted to support users in addressing discriminatory practices and human rights violations.

Current Therapeutic Cannabis Controversies and Clinical Trial Design Issues

This overview covers a wide range of cannabis topics, initially examining issues in dispensaries and self-administration, plus regulatory requirements for production of cannabis-based medicines, particularly the Food and Drug Administration "Botanical Guidance." The remainder pertains to various cannabis controversies that certainly require closer examination if the scientific, consumer, and governmental stakeholders are ever to reach consensus on safety issues, specifically: whether botanical cannabis displays herbal synergy of its components, pharmacokinetics of cannabis and dose titration, whether cannabis medicines produce cyclo-oxygenase inhibition, cannabis-drug interactions, and cytochrome P450 issues, whether cannabis randomized clinical trials are properly blinded, combatting the placebo effect in those trials via new approaches, the drug abuse liability (DAL) of cannabis-based medicines and their regulatory scheduling, their effects on cognitive function and psychiatric sequelae, immunological effects, cannabis and driving safety, youth usage, issues related to cannabis smoking and vaporization, cannabis concentrates and vape-pens, and laboratory analysis for contamination with bacteria and heavy metals. Finally, the issue of pesticide usage on cannabis crops is addressed. New and disturbing data on pesticide residues in legal cannabis products in Washington State are presented with the observation of an 84.6% contamination rate including potentially neurotoxic and carcinogenic agents. With ongoing developments in legalization of cannabis in medical and recreational settings, numerous scientific, safety, and public health issues remain.

Tobacco plain packaging: Evidence based policy or public health advocacy?

In December 2012, Australia became the first country to require all tobacco products be sold solely in standardised or 'plain' packaging, bereft of the manufacturers' trademarked branding and colours, although retaining large graphic and text health warnings. Following the publication of Sir Cyril Chantler's review of the evidence on the effects of plain tobacco packaging, the Ministers of the United Kingdom Parliament voted in March 2015 to implement similar legislation. Support for plain packaging derives from the belief that tobacco products sold in plain packs have reduced appeal and so are more likely to deter young people and non-smokers from starting tobacco use, and more likely to motivate smokers to quit and stay quit. This article considers why support for the plain packaging policy has grown among tobacco control researchers, public health advocates and government ministers, and reviews Australian survey data that speak to the possible introductory effect of plain packaging on smoking prevalence within Australia. The article concludes by emphasising the need for more detailed research to be undertaken before judging the capacity of the plain packaging policy to deliver the multitude of positive effects that have been claimed by its most ardent supporters.

Paranoid personality disorder in the United States: the role of race, illicit drug use, and income

Differential rates of schizophrenia and paranoia symptoms have been found for Black and White individuals. Paranoid personality disorder shares symptoms with schizophrenia, yet has received minimal attention with regard to potential racial differences. In a sample consisting of 180 substance use disorder treatment-seeking individuals, the association between the diagnosis of paranoid personality disorder and the variables of race, cannabis use disorder, and income were examined. Results extended previous findings to paranoid personality disorder, supporting the hypothesis that Black individuals would be diagnosed with higher rates of paranoid personality disorder. Cannabis use disorder status and income did not predict paranoid personality disorder diagnoses.

Cannabis controversies: how genetics can inform the study of comorbidity

AIMS

To review three key and controversial comorbidities of cannabis use-other illicit drug use, psychosis and depression, as well as suicide, from a genetically informed perspective.

DESIGN

Selective review.

RESULTS

Genetic factors play a critical role in the association between cannabis use, particularly early-onset use and use of other illicit drugs, psychosis and depression, as well as suicide, albeit via differing mechanisms. For other illicit drugs, while there is strong evidence for shared genetic influences, residual association that is attributable to causal or person-specific environmental factors cannot be ruled out. For depression, common genetic influences are solely responsible for the association with cannabis use but for suicidal attempt, evidence for person-specific factors persists. Finally, even though rates of cannabis use are inordinately high in those with psychotic disorders, there is no evidence of shared genetic etiologies underlying this comorbidity. Instead, there is limited evidence that adolescent cannabis use might moderate the extent to which diathesis influences psychosis.

CONCLUSIONS

Overlapping genetic influences underlie the association between early-onset cannabis use and other illicit drug use as well as depression and suicide. For psychosis, mechanisms other than shared genetic influences might be at play.

Stronger evidence is needed before accepting that cannabis plays an important role in the aetiology of schizophrenia in the population

Schizophrenia is a debilitating but poorly understood condition with very few known modifiable risk factors. Cannabis use can acutely induce psychotic experiences, but its causal relationship to schizophrenia is less well understood. Longitudinal cohort studies suggest that the association between cannabis and psychotic outcomes is not due to chance or reverse causation. However, the association could be due to bias or residual confounding. Methods that can test alternative explanations in greater depth are required. This is especially important as ecological studies have found little association between the increase in cannabis use over recent decades and incidence of psychotic disorders; public health models suggest that cannabis use may need to be treated and prevented in many thousands of users in order to prevent one case of schizophrenia. We believe that, while such uncertainty exists, there is a scientific duty to continue to investigate the role of cannabis in the aetiology of schizophrenia and that the policy case for considering cannabis exposure as a critical target for preventing schizophrenia is yet to be made. However, due to other evidence of the harms of cannabis use, this should not affect the public health message that cannabis can be harmful and that cannabis dependence should be prevented.

Societal images of Cannabis use: comparing three countries

Background

Differences in beliefs about Cannabis were compared between Canada, Sweden and Finland using nationally representative population surveys containing similar items.

Findings

Compared to Finnish and Swedish respondents, Canadians were both more likely to have tried Cannabis and to view Cannabis as a less serious problem for society.

Conclusions

These findings emphasize the extent to which views about Cannabis can vary. It is possible that views about Cannabis are, at least in part, a social construction influenced by media, social policy and exposure to the drug that varies from country to country.

A damage/benefit evaluation of addictive product use

AIMS

To obtain damage/benefit assessments of eight commonly used addictive products and one addictive behaviour from French addiction experts and link these to overall evaluations.

DESIGN AND SETTING

Criteria-based evaluation by experts in addiction. Specific statistical modelling to estimate the relative contribution of various criteria to formulating expert general opinion on products.

PARTICIPANTS

Forty-eight French experts in addiction.

MEASUREMENTS

Twelve criteria covering the whole spectrum of damages and benefits to users and to society evaluated using visual analogue scales (VAS). Direct measure of expert overall subjective opinions on products from user and from social perspectives.

FINDINGS

Damage scoring identified alcohol (damage score = 48.1), heroin (damage score = 44.9) and cocaine (damage score = 38.5) as the most harmful products to users and to society; gambling was considered the least harmful (score = 22.5), replicating previous results. Damage scoring correlated poorly with legal status or with overall subjective expert opinions of products. Benefit perception scores indicated alcohol as a clear outlier (benefit score = 45.5) followed by tobacco (benefit score = 34.3) and cannabis (benefit score = 31.1). Statistical modelling suggested that experts attributed 10 times more importance to benefit perception than to damages when making their subjective opinion from a user perspective and two times more importance to benefit perception than to damages in formulating their opinion from a social perspective.

CONCLUSIONS

The perceived benefits of addictive products appear to have a major impact on the opinion of those products expressed by a number of French addiction experts.

Marijuana: modern medical chimaera

Marijuana has been used medically since antiquity. In recent years there has been a resurgence of interest in medical applications of various cannabis preparations. These drugs have been cited in the medical literature as potential secondary treatment agents for severe pain, muscle spasticity, anorexia, nausea, sleep disturbances, and numerous other uses. This article reviews the research literature related to medical applications of various forms of cannabis. Benefits related to medical use of cannabinoids are examined and a number of potential risks associated with cannabis use, both medical and recreational, are considered. There is a clearly identified need for further research to isolate significant benefits from the medical application of cannabinoids and to establish dosage levels, appropriate delivery mechanisms and formulations, and to determine what role, if any, cannabinoids might play in legitimate medical applications. It is also imperative to determine if reported dangers pose a significant health risks to users.