Inleiding en context

Beste mensen het is vrijdag 30 september 2022, alweer de laatste werkdag van de week en van deze maand. Nog een kleine drie maanden en de kerstboom in de kamer is weer een feit. Op de valreep van deze werkweek nog een compilatie van een viertal ´kennispareltjes´. Het gaat dan om een aantal bijdragen waaruit blijkt dat het gebruik van cannabis niet geheel ongevaarlijk is. Daarom dit liedje over reefers: https://www.youtube.com/watch?v=jDb2xNsa2YA

Zo blijkt dat het gebruik van cannabis negatieve gevolgen kan hebben voor de directe sociale omgeving. Gebruikers van cannabis in het verkeer brengen zichzelf en anderen bovengemiddeld in gevaar. Cannabisgebruik kan geweldsmisdrijven tot gevolg hebben. Cannabisgebruik op jonge leeftijd heeft grote negatieve gevolgen voor het functioneren van de gebruiker. Tjonge, toch even om over na te denken, ook binnen het Nederlandse drugsbeleid. En dan ga ik niet eens in op de problematiek op georganiseerde misdaadmarkten in relatie tot de illegale productie van cannabis.

Bron

Fischer, Benedikt, Sheila Rubia Lindner & Wayne Hall (September 2022). Cannabis use and public health: Time for a comprehensive harm-to-others framework. The Lancet Public Health, vol. 7, no. 10. October, pp. 808-809.

https://www.sciencedirect.com/science/article/pii/S2468266722002055

Summary

This evidence suggests several different ways in which cannabis use could cause substantive harm to others, including the—still overall—majority of individuals who do not use cannabis, and who might include family members, children, or friends of users. The size of the risks of the main possible harm-to-others outcomes illustrated here are comparatively moderate, but should not be neglected in public policies, interventions, or monitoring of the overall harms of cannabis use. The consequential social costs can be added to these direct harms, such as health-care expenditures and productivity losses, that can arise from cannabis use and are borne by society. Our observations emphasise that conceptual and empirical perspectives on health harms arising from cannabis use cannot solely focus on harms to the health of users. In particular, jurisdictions that make efforts to liberalise cannabis control frameworks to advance public health objectives need to also consider and address the possible cannabis-related harm to others.

Bron

Fischer, Benedikt et al. (January 2022). Lower-Risk Cannabis Use Guidelines (LRCUG) for reducing health harms from non-medical cannabis use: A comprehensive evidence and recommendations update. International Journal of Drug Policy, vol. 99, no. 1, January, pp.

https://www.sciencedirect.com/science/article/pii/S0955395921002863?via%3Dihub

Summary

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.

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.

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.

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.

Bron

Preuss, Ulrich W. et al. (May 2021). Cannabis Use and Car Crashes: A Review. Frontiers in Psychiatry, vol. 12, May, pp. 1-11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8195290/

Summary

In this review, state-of-the-art evidence on the relationship between cannabis use, traffic crash risks, and driving safety were analyzed. Systematic reviews, meta-analyses, and other relevant papers published within the last decade were systematically searched and synthesized. Findings show that meta-analyses and culpability studies consistently indicate a slightly but significantly increased risk of crashes after acute cannabis use. These risks vary across included study type, crash severity, and method of substance application and measurement. Some studies show a significant correlation between high THC blood concentrations and car crash risk. Most studies do not support this relationship at lower THC concentrations. However, no scientifically supported clear cut-off concentration can be derived from these results. Further research is needed to determine dose-response effects on driving skills combined with measures of neuropsychological functioning related to driving skills and crash risk.

Bron

Dellazizzo, Laura et al. (September 2020). Violence and Cannabis Use: A Focused Review of a Forgotten Aspect in the Era of Liberalizing Cannabis. Frontiers in Psychiatry, vol. 11, September, pp. 1-11. https://www.frontiersin.org/articles/10.3389/fpsyt.2020.567887/full

Summary

There has been a shift surrounding societal and legal perspectives on cannabis reflecting changing public attitudes towards the perceived safety and social acceptability of cannabis use. With cannabis liberalization internationally, the focus of most cannabis-related harms has been on effects with users themselves. Harm-to-others including injuries from violence have nevertheless been unfortunately largely overlooked. While studies remain heterogeneous, there is meta-analytical evidence pointing towards an association.

The aims of this focused review are two-fold: (I) review the evidence from meta-analyses on the association between cannabis and violence; and (II) provide an overview of possible mechanisms relating cannabis use to violence. First, evidence from meta-analytical studies in youths, intimate partners, and individuals with severe mental disorders have shown that there is a global moderate association between cannabis use and violence, which is stronger in the latter more at-risk population. Preliminary data has even highlighted a potential dose-response relationship with larger effects in more frequent users. Although of importance, this subject has remained essentially forgotten as a public health concern.

While literature remains inconclusive, data has suggested potential increases in cannabis use following liberalization policies. This may increase violent outcomes if the effect is directly related to the use of cannabis by means of its psychophysiological modifications. However, for the moment, the mechanisms associating cannabis use and violence remain to be clearly resolved. Considering the recency of policy changes on cannabis, further methodologically sound research using longitudinal designs should examine the effects that cannabis use may have on different forms of violence and the trends that emerge, while evaluating the effects of possible confounding factors (e.g. other substance use). In addition, as evidence-based research from meta-analyses have shown that cannabis use is associated with violence, measures must be taken to mitigate the risks.

Afsluitend

Het gebruik van cannabis blijkt dus op basis van de bijgesloten vier ´kennisparels´ voor sommige gebruikersgroepen niet geheel ongevaarlijk. De rouwrandjes van dat gebruik blijken misschien toch wat meer omvangrijk dan wat onderzoekers, beleidsmakers, belangenpartijen en politici ons willen doen geloven. Naar mijn mening is het niet alleen nuttig maar ook noodzakelijk dat beleidsmakers bij het formuleren van cannabisbeleid ook deze inzichten gebruiken. Opnieuw kennis om van te leren.