Cannabis Use and Car Crashes: A Review

Efficiency and safety of cannabinoid medical use: an analysis of discussions and observed trends on Instagram

Background

Cannabis and its derivatives show encouraging therapeutic effects in the treatment of various diseases. However, further studies are needed to better assess their efficacy and safety. A promising base for research in the field of medicine and additional pharmacovigilance is social networks, in which experience and knowledge are exchanged between researchers, doctors, and patients, as well as information about the potential risks and benefits of using drugs for medical purposes is disseminated. The aim of this study was to investigate the reported efficiency and safety of medical use of cannabinoids in patients using posts on the social media Instagram and analyze the observed trends.

Methods

Social media listening platform Apify was used to collect data with hashtags as of June 4, 2024, including posts from 2023 and 2024, with some data extending into later periods, in compliance with a systematic approach to data collection. The analysis of the data obtained from the research was conducted using the RStudio platform.

Results

The analysis covered 1,466 posts containing hashtags related to cannabinoids. The posts studied were categorized as follows: 33.08% focused on advertising and commercialization, 25.58% on personal experience, 21.35% on other topics, and 19.99% contained educational content. An analysis of overall content relevance found that the majority of Instagram posts (81.79%) related to cannabis and cannabinoid hashtags are relevant. Most of the Instagram posts studied were posters, followed by personal photos and videos. The analysis shows that English dominates the studied category (70.74% of posts), while German, French, Spanish, and other languages also occupy a significant place, emphasizing the importance of a multilingual approach in content analysis. It has been revealed that organizations publish a larger percentage of posts under this study, with a higher percentage of relevance. Personal experience stories receive a significant number of "likes" indicating a strong emotional connection between audience and content. Instagram discussions about cannabinoid treatment support evidence from scientific studies about their effectiveness in treating a range of diseases, such as epilepsy with Lennox-Gastaut and Dravet syndromes, multiple sclerosis, cancer, and HIV-cachexia, nausea and vomiting caused by chemotherapy. At the same time, they emphasize the need for further clinical studies to better assess safety, side effects, and optimal dosages. Advertising and commercial posts can contribute to increased cannabis use, highlighting the need to raise awareness of risks and strengthen preventive measures.

Conclusion

Analysis of content on the social media Instagram can complement traditional scientific research by providing information on the real use of cannabis and its derivatives, contributing to the development of safe and effective recommendations for its use.

Cannabinoid Hyperemesis Syndrome (CHS) - An emerging gastrointestinal disorder and clinical challenge

Nausea and vomiting are not uncommon symptoms resulting in emergency department (ED) or primary care visits. One of the emerging etiologies - Cannabinoid Hyperemesis Syndrome (CHS) remains significantly under-diagnosed, often resulting in unnecessary repeat ED visits and testing. This is in part due to lack of experience with and knowledge about CHS by health care professionals. Characterized by cyclic vomiting, often severe and intractable, it is frequently associated with a form of self-treatment; the compulsive need to take hot showers, and in the context of chronic cannabis use. With increased legalization and resultant accessibility to cannabis containing products, the risk of adverse events is significantly rising. Lack of clinical familiarity with the range of potential deleterious physical and mental health effects associated with cannabis leads to delays in appropriate diagnosis and effective treatment of CHS. Moreover, commonly utilized anti-emetics, such as ondansetron, and similar 5 HT drugs may not fully attenuate symptoms of CHS, and other interventions may be necessary; ultimately abstinence being the most effective long term clinical preventive approach. The objective of this review article is to assist the clinician in identifying the specific clinical characteristics of CHS, distinguishing it from other causes of CVS or nausea and vomiting, to facilitate more rapid, effective interventions. Collaboration with substance use professionals should also be considered during CHS treatment.

Reliability of roadside oral fluid testing devices for ∆9-tetrahydrocannabinol (∆9-THC) detection

Driving under the influence of cannabis (DUIC) is increasing worldwide, and cannabis is the most prevalent drug after alcohol in impaired driving cases, emphasizing the need for a reliable traffic enforcement strategy. ∆9-tetrahydrocannabinol (THC) detection in oral fluid has great potential for identifying recent cannabis use; however, additional data are needed on the sensitivities, specificities, and efficiencies of different oral fluid devices for detecting cannabinoids at the roadside by police during routine traffic safety enforcement efforts. At the roadside, 8945 oral fluid THC screening tests were performed with four devices: AquilaScan®, Dräger DrugTest®, WipeAlyser Reader®, and Druglizer®. A total of 530 samples screened positive for THC (5.9%) and were analyzed by liquid chromatography-tandem mass spectrometry at multiple cutoff concentrations (2 ng/mL, 10 ng/mL, and manufacturers' recommended device cutoffs) to investigate device performance. Results varied substantially, with sensitivities of 0%-96.8%, specificities of 89.8%-98.5%, and efficiencies of 84.3%-97.8%. The Dräger DrugTest® outperformed the other devices with a 96.8% sensitivity, 97.1% specificity, and 97.0% efficiency at a 5-ng/mL LC-MS/MS confirmation cutoff. The WipeAlyser Reader® had good performance with a 91.4% sensitivity, 97.2% specificity, and 96.4% efficiency. AquilaScan® and Druglizer® had unacceptable performance for cannabinoid detection, highlighted by sensitivity <13%. The choice of roadside oral fluid testing device must offer good analytical performance for cannabinoids because of its high prevalence of use and impact on road safety.

Opinions of French psychiatrists on the regulatory status of cannabis: Results from the "PsyCan - Encéphale" national online survey

OBJECTIVE

To explore the opinions of French psychiatrists toward the legalization of medical or recreational use of cannabis in France.

METHODS

Psycan was an anonymous Internet survey conducted between September 28, 2021 and March 29, 2022, among subscribers of the Encéphale Online community, i.e., approximately 4000 French psychiatrists. Participants were asked to complete a structured questionnaire, collecting their socio-demographic features, clinical experience, opinions toward cannabis legalization, and perceived impact of cannabis derivatives for psychiatric disorders. Logistic regression models were used to identify factors associated with being for or against cannabis legalization.

RESULTS

In total, 413 psychiatrists answered the survey, of whom 253 (61.3%) declared being in favour of recreational cannabis, and 349 (84.4%) of medical cannabis. Being in favour of legalization of recreational cannabis was negatively associated with being female (odd ratio [OR]=0.61; 95% confidence interval [CI]=0.41-0.93), and with the frequency of meeting patients with cannabis use disorder (OR=0.60; 95%CI=0.43-0.83). Most respondents were concerned about the development of psychotic disorders. The most frequent pro-legalization arguments were improved prevention, better control of product content, and better protection of youth, respectively. Arguments against legalization were increased societal damages, increased impact on health, including mental health.

CONCLUSIONS

A majority of French psychiatrists were in favour of the marketing of medical cannabis, and, to a lesser extent, the legalization of recreational cannabis. For recreational cannabis, the proportion of pro-legalization psychiatrists was slightly more elevated than that found in the French general population.

Cannabis, cannabinoids and health: a review of evidence on risks and medical benefits

The legalization of cannabis for medical and recreational purposes has progressed internationally. Cannabis and cannabinoids are advocated for a plethora of medical indications. An increasing number of medical and nonmedical users regularly consume large doses of delta-9-Tetrahydrocannabinol (THC), the main active component of cannabis. Aim: to summarize the evidence on (1) risks of recreational cannabis use and (2) effectiveness and safety of medicinal cannabis. Findings on recreational use: Cannabis is mostly used to experience its acute rewarding effects. Regular use of high THC products can produce addiction (cannabis use disorder or CUD). Acute consumption of high THC doses (including unintentionally) can cause time-limited mental, gastrointestinal, and cardiovascular problems and motor vehicle accidents. Chronic patterns of cannabis use have been associated with multiple adverse outcomes that are of particular concern among adolescents and young adults, such as, disrupted learning, impaired cognitive performance, reduced educational attainment and an increased risk of CUD, psychosis/schizophrenia, mood and anxiety disorders and suicidal behaviors. There is debate about the extent to which cannabis use is a cause of these adverse outcomes. Physical health risks (e.g., respiratory and cardiovascular, prematurity and restricted fetal growth, hyperemesis syndrome among others) have also been linked with repeated consumption of cannabis with a high THC content. Findings on medical cannabis use: Herbal cannabis, medicines from extracted or synthetized cannabinoids-often used as adjuvants to standard medicines-may produce small to modest benefits. This is primarily the case in treating chronic pain, muscle spasticity, chemotherapy-induced nausea and vomiting, and refractory epilepsy (in the case of cannabidiol, CBD). The evidence is inconclusive on their value in treating mental disorders and other medical conditions. Safety: Cannabis-based medicine is generally well tolerated. There is a risk of mild to moderate adverse effects and CUD.

Road hazard: a systematic review of traffic injuries following recreational cannabis legalization

PURPOSE

Acute cannabis use is associated with impaired driving performance and increased risk of motor vehicle crashes. Following the Canadian Cannabis Act's implementation, it is essential to understand how recreational cannabis legalization impacts traffic injuries, with a particular emphasis on Canadian emergency departments. This study aims to assess the impact of recreational cannabis legalization on traffic-related emergency department visits and hospitalizations in the broader context of North America.

METHODS

A systematic review was conducted according to best practices and reported using PRISMA 2020 guidelines. The protocol was registered on July 5, 2022 (PROSPERO CRD42022342126). MEDLINE(R) ALL (OvidSP), Embase (OvidSP), CINAHL (EBSCOHost), and Scopus were searched without language or date restrictions up to October 12, 2023. Studies were included if they examined cannabis-related traffic-injury emergency department visits and hospitalizations before and after recreational cannabis legalization. The risk of bias was assessed. Meta-analysis was not possible due to heterogeneity.

RESULTS

Seven studies were eligible for the analysis. All studies were conducted between 2019 and 2023 in Canada and the United States. We found mixed results regarding the impact of recreational cannabis legalization on emergency department visits for traffic injuries. Four of the studies included reported increases in traffic injuries after legalization, while the remaining three studies found no significant change. There was a moderate overall risk of bias among the studies included.

CONCLUSIONS

This systematic review highlights the complexity of assessing the impact of recreational cannabis legalization on traffic injuries. Our findings show a varied impact on emergency department visits and hospitalizations across North America. This underlines the importance of Canadian emergency physicians staying informed about regional cannabis policies. Training on identifying and treating cannabis-related impairments should be incorporated into standard protocols to enhance response effectiveness and patient safety in light of evolving cannabis legislation.

Traumatic Brain Injury Outcomes After Recreational Cannabis Use

Purpose

Basic science data indicate potential neuroprotective effects of cannabinoids in traumatic brain injury (TBI). We aimed to evaluate the effects of pre-TBI recreational cannabis use on TBI outcomes.

Patients and Methods

We used i2b2 (a scalable informatics framework; www.i2b2.org) to identify all patients presenting with acute TBI between 1/1/2014 and 12/31/2016, then conducted a double-abstraction medical chart review to compile basic demographic, urine drug screen (UDS), Glasgow Coma Scale (GCS), and available outcomes data (mortality, modified Rankin Scale (mRS), duration of stay, disposition (home, skilled nursing facility, inpatient rehabilitation, other)) at discharge and at specific time points thereafter. We conducted multivariable nested ordinal and logistic regression analyses to estimate associations between cannabis use, other UDS results, demographic factors, and selected outcomes.

Results

i2b2 identified 6396 patients who acutely presented to our emergency room with TBI. Of those, 3729 received UDS, with 22.2% of them testing positive for cannabis. Mortality was similar in patients who tested positive vs negative for cannabis (3.9% vs 4.8%; p = 0.3) despite more severe GCS on admission in the cannabis positive group (p = 0.045). Several discharge outcome measures favored the cannabis positive group who had a higher rate of discharge home vs other care settings (p < 0.001), lower discharge mRS (p < 0.001), and shorter duration of hospital stay (p < 0.001) than the UDS negative group. Multivariable analyses confirmed mostly independent associations between positive cannabis screen and these post-TBI short- and long-term outcomes.

Conclusion

This study adds evidence about the potentially neuroprotective effects of recreational cannabis for short- and long-term post-TBI outcomes. These results need to be confirmed via prospective data collections.

Impact of Early-Life Adversity on Cannabis Use: Exploring the Mediating and Moderating Effects of Chronic Pain

Background: Although research suggests that early-life adversity (ELA) and cannabis use are linked, researchers have not established factors that mediate or modify this relationship. Identifying such factors could help in developing targeted interventions. We explored chronic pain as a potential mediator or moderator of this relationship. Methods: Using an online study, we collected cross-sectional data about ELA, cannabis use, and chronic pain to test whether ELA (adverse childhood experiences total score) is associated with cannabis use, and to examine pain as a potential mediator or moderator. Cannabis use was examined two ways: times used per day, and categorized as non-, some, or regular use. Chronic pain was measured as present/absent and as the number of painful body locations (0-8). Analyses used linear and multinomial regression. Results: ELA, chronic pain, and cannabis use were common among respondents. ELA was strongly associated with both measures of cannabis use. The number of painful body locations modestly mediated the association of ELA with cannabis use, reducing the magnitude of regression coefficients by about 1/7. The number of painful body locations modified the association between ELA and cannabis use (p≤0.006), while chronic pain presence/absence (a less-informative measure) had only a nonsignificant modification effect (p≥0.10). When either ELA or pain was high, the other was not associated with cannabis use; when either ELA or pain was low, more painful locations or higher ELA (respectively) was associated with more intense cannabis use. Conclusion: These exploratory findings suggest the importance of ELA and chronic pain as factors contributing to cannabis use, and of accounting for these factors in developing treatment and prevention strategies addressing cannabis use.

Cannabis use and cannabis use disorders and their treatment in the Europe

This paper introduces the special issue on cannabis use in Europe. It describes data on the prevalence of cannabis use in Europe and the more limited data on the prevalence of cannabis use disorders, one of the most common forms of drug problem treated in many countries in Europe. It summarises what research has indicated about the adverse effects of acute and chronic cannabis use and discusses potential health system responses that may reduce some of these harms. These include public education about the risks of cannabis use; screening and brief interventions in primary medical settings; and specialist treatment for cannabis use disorders. It briefly indicates the special issues that may need to be addressed in dealing with the high rates of comorbidity between cannabis use disorders, other types of drug use disorders, and common mental disorders.

Recent advances in the development of portable technologies and commercial products to detect Δ9-tetrahydrocannabinol in biofluids: a systematic review

BACKGROUND

The primary components driving the current commercial fascination with cannabis products are phytocannabinoids, a diverse group of over 100 lipophilic secondary metabolites derived from the cannabis plant. Although numerous phytocannabinoids exhibit pharmacological effects, the foremost attention has been directed towards Δ9-tetrahydrocannabinol (THC) and cannabidiol, the two most abundant phytocannabinoids, for their potential human applications. Despite their structural similarity, THC and cannabidiol diverge in terms of their psychotropic effects, with THC inducing notable psychological alterations. There is a clear need for accurate and rapid THC measurement methods that offer dependable, readily accessible, and cost-effective analytical information. This review presents a comprehensive view of the present state of alternative technologies that could potentially facilitate the creation of portable devices suitable for on-site usage or as personal monitors, enabling non-intrusive THC measurements.

METHOD

A literature survey from 2017 to 2023 on the development of portable technologies and commercial products to detect THC in biofluids was performed using electronic databases such as PubMed, Scopus, and Google Scholar. A systematic review of available literature was conducted using Preferred Reporting Items for Systematic. Reviews and Meta-analysis (PRISMA) guidelines.

RESULTS

Eighty-nine studies met the selection criteria. Fifty-seven peer-reviewed studies were related to the detection of THC by conventional separation techniques used in analytical laboratories that are still considered the gold standard. Studies using optical (n = 12) and electrochemical (n = 13) portable sensors and biosensors were also identified as well as commercially available devices (n = 7).

DISCUSSION

The landscape of THC detection technology is predominantly shaped by immunoassay tests, owing to their established reliability. However, these methods have distinct drawbacks, particularly for quantitative analysis. Electrochemical sensing technology holds great potential to overcome the challenges of quantification and present a multitude of advantages, encompassing the possibility of miniaturization and diverse modifications to amplify sensitivity and selectivity. Nevertheless, these sensors have considerable limitations, including non-specific interactions and the potential interference of compounds and substances existing in biofluids.

CONCLUSION

The foremost challenge in THC detection involves creating electrochemical sensors that are both stable and long-lasting while exhibiting exceptional selectivity, minimal non-specific interactions, and decreased susceptibility to matrix interferences. These aspects need to be resolved before these sensors can be successfully introduced to the market.

Fatal crashes and rare events logistic regression: an exploratory empirical study

Objective

Fatal road accidents are statistically rare, posing challenges for accurate estimation through the classic logit model (LM). This study seeks to validate the efficacy of a rare events logistic model (RELM) in enhancing the precision of fatal crash estimations.

Methods

Both LM and RELM were employed to examine the relationship between pertinent risk factors and the incidence of fatal crashes. Crash-injury datasets sourced from Hillsborough County, Florida served as the empirical basis for evaluating the performance metrics of both LM and RELM.

Results

The analysis revealed that RELM yielded more accurate predictions of fatal crashes compared to LM. Receiver operating characteristic (ROC) curves were constructed, and the area under the curve (AUC) for each model was computed to offer a comparative performance assessment. The empirical evidence notably favored RELM over LM as substantiated by superior AUC values.

Conclusion

The study offers empirical validation that RELM is demonstrably more proficient in predicting fatal crashes than the LM, thereby recommending its application for nuanced traffic safety analytics.

Cannabis and Driving in Older Adults

Importance

Epidemiological studies have found that cannabis increases the risk of a motor vehicle collision. Cannabis use is increasing in older adults, but laboratory studies of the association between cannabis and driving in people aged older than 65 years are lacking.

Objective

To investigate the association between cannabis, simulated driving, and concurrent blood tetrahydrocannabinol (THC) levels in older adults.

Design, Setting, and Participants

Using an ecologically valid counterbalanced design, in this cohort study, regular cannabis users operated a driving simulator before, 30 minutes after, and 180 minutes after smoking their preferred legal cannabis or after resting. This study was conducted in Toronto, Canada, between March and November 2022 with no follow-up period. Data were analyzed from December 2022 to February 2023.

Exposures

Most participants chose THC-dominant cannabis with a mean (SD) content of 18.74% (6.12%) THC and 1.46% (3.37%) cannabidiol (CBD).

Main outcomes and measures

The primary end point was SD of lateral position (SDLP, or weaving). Secondary outcomes were mean speed (MS), maximum speed, SD of speed, and reaction time. Driving was assessed under both single-task and dual-task (distracted) conditions. Blood THC and metabolites of THC and CBD were also measured at the time of the drives.

Results

A total of 31 participants (21 male [68%]; 29 White [94%], 1 Latin American [3%], and 1 mixed race [3%]; mean [SD] age, 68.7 [3.5] years), completed all study procedures. SDLP was increased and MS was decreased at 30 but not 180 minutes after smoking cannabis compared with the control condition in both the single-task (SDLP effect size [ES], 0.30; b = 1.65; 95% CI, 0.37 to 2.93; MS ES, -0.58; b = -2.46; 95% CI, -3.56 to -1.36) and dual-task (SDLP ES, 0.27; b = 1.75; 95% CI, 0.21 to 3.28; MS ES, -0.47; b = -3.15; 95% CI, -5.05 to -1.24) conditions. Blood THC levels were significantly increased at 30 minutes but not 180 minutes. Blood THC was not correlated with SDLP or MS at 30 minutes, and SDLP was not correlated with MS. Subjective ratings remained elevated for 5 hours and participants reported that they were less willing to drive at 3 hours after smoking.

Conclusions and relevance

In this cohort study, the findings suggested that older drivers should exercise caution after smoking cannabis.

A two-sample approach to retrograde extrapolation of blood THC concentrations - Is it feasible?

BACKGROUND

Retrograde extrapolation of drug concentrations in blood can be relevant in cases of drug-impaired driving and is regularly used in forensic toxicology in Norway. Δ9-tetrahydrocannabinol (THC) has complex, multi-compartmental pharmacokinetics, which makes retrograde extrapolation of blood THC concentrations problematic. In the present study, we evaluated an approach to retrograde extrapolation in which momentary rates of decrease of THC were estimated from two consecutive blood samples in apprehended drivers.

MATERIAL AND METHODS

Data were collected from apprehended drivers in Norway 2000-2020. We included 548 cases in which THC was detected in two consecutive blood samples collected ≥ 20 min apart. THC concentrations were measured by GC-MS and UHPLC-MS/MS. In each case, THC concentrations and the time between the two sampling points (Δt) were used to estimate the rate constant k. The relationship between THC concentration and k was modelled by linear regression.

RESULTS

The median Δt was 31 min (interquartile range, IQR = 9). The median blood THC concentration was 2.4 μg/L (IQR = 3.4) at the first sampling point and 2.3 μg/L (IQR =3.1) at the second. The concentration decreased in 62% and increased in 38% of all cases. However, considering measurement uncertainty, the changes were not statistically significant in 87% of cases. The mean of k was 0.12 h-1, corresponding to an apparent t1/2 of 6.0 h. The t1/2 predicted from linear regression of k against THC concentration ranged from 0.93 to 13 h for the highest and lowest concentrations observed (36 and 0.63 μg/L, respectively). The time from driving to blood collection had a median of 1.7 h (IQR = 1.5), and did not correlate with k.

CONCLUSIONS

The apparent t1/2 of THC calculated from the mean of k was 6.0 h, which is shorter than the terminal elimination t1/2 suggested in previous population studies. This indicates that blood samples were often taken during the late distribution phase of THC. Because Δt was short relative to the rates of decrease expected in the late distribution and elimination phases, the underlying true concentration changes related to in vivo pharmacokinetics were small and masked by the relatively larger "false" changes introduced by random analytical and pre-analytical error. Therefore, individual values of k calculated from only two blood samples taken a short time apart are unreliable, and a two-sample approach to retrograde extrapolation of THC cannot be recommended.

Substance use and pre-hospital crash injury severity among U.S. older adults: A five-year national cross-sectional study

BACKGROUND

Alcohol and drug use (substance use) is a risk factor for crash involvement.

OBJECTIVES

To assess the association between substance use and crash injury severity among older adults and how the relationship differs by rurality/urbanicity.

METHODS

We pooled 2017-2021 cross-sectional data from the United States National Emergency Medical Service (EMS) Information System. We measured injury severity (low acuity, emergent, critical, and fatal) predicted by substance use, defined as self-reported or officer-reported alcohol and/or drug use. We controlled for age, sex, race/ethnicity, road user type, anatomical injured region, roadway crash, rurality/urbanicity, time of the day, and EMS response time. We performed a partial proportional ordinal logistic regression and reported the odds of worse injury outcomes (emergent, critical, and fatal injuries) compared to low acuity injuries, and the predicted probabilities by rurality/urbanicity.

RESULTS

Our sample consisted of 252,790 older adults (65 years and older) road users. Approximately 67%, 25%, 6%, and 1% sustained low acuity, emergent, critical, and fatal injuries, respectively. Substance use was reported in approximately 3% of the population, and this proportion did not significantly differ by rurality/urbanicity. After controlling for patient, crash, and injury characteristics, substance use was associated with 36% increased odds of worse injury severity. Compared to urban areas, the predicted probabilities of emergent, critical, and fatal injuries were higher in rural and suburban areas.

CONCLUSION

Substance use is associated with worse older adult crash injury severity and the injury severity is higher in rural and suburban areas compared to urban areas.

Legalization of marijuana or not? Opinions from over 38,000 residents in Taiwan

BACKGROUND

Marijuana is legal in many Western countries and Thailand. In Taiwan, Marijuana remains a category-2 narcotic; however, some legislative candidates recently advocated legalization of medical marijuana. This study surveyed a large sample of Taiwanese to gain a better understanding of the public's knowledge and attitudes towards legalizing marijuana.

METHODS

This cross-sectional mixed-methods study included demographic data and responses to a survey questionnaire, "Knowledge and Attitudes of Legalizing Marijuana" (KALM). The survey included 15 statements about four categories: public health, social impact, medical applications of THC (Δ9-tetrahydrocannabinol), and legal and tax consequences; and two yes/no questions about medical use and legalization of marijuana. Knowledge was scored as disagree = 0, no knowledge = 2, or agree = 4; attitude was scored from 0 = very unimportant to 4 = very important. Responses to an open-ended question asking for additional comments/concerns were analysed with content analysis. The survey was conducted from February 15 to March 1, 2023.

RESULTS

Data were analysed from 38,502 respondents, aged 15 to > 56 years. Most were female (67.1%) and parents (76.4%). Scores were higher for respondents who were parents, religious, ≥ 36 years of age, had a high-income status, no history of substance abuse, knowledge of medical marijuana, and did not support legalization of marijuana. Medical personnel had greater knowledge of marijuana, but their attitude indicated they viewed legalization as less important. In the open-ended question, many respondents requested more information about marijuana be provided to the public before considering legalization.

CONCLUSIONS

Taiwanese respondents considered legalization of marijuana a significant concern, especially as it relates to impacts on public health.

Trends in Fatal Poisoning Among Drug Users in France From 2011 to 2021: An Analysis of the DRAMES Register

Importance

The DRAMES (Décès en Relation avec l'Abus de Médicaments Et de Substances) register is a database of drug-related deaths with the aim of identifying the psychoactive substances associated with and estimating the trends in these deaths. Our novel approach is based on the collection of data on all deaths for which toxicology experts have performed analyses.

Objective

To describe drug-related deaths in France and report trends over an 11-year period.

Design, Setting, and Participants

This case series used a national register to assess 4460 drug-related deaths that occurred from 2011 to 2021 in France. Data analyses were performed from January 1, 2012, to December 31, 2022.

Main Outcomes and Measures

Demographic characteristics; medical and substance abuse history; forensic autopsy findings; and toxicology reports.

Results

Among the 4460 deceased individuals (mean [SD] age, 37.8 [10.5] years), the mortality rate was highest among men (sex ratio, 4.4:1). Of the deaths involving a single or predominant drug, the legal substitution product, methadone, was the leading cause of death during the entire study period, ahead of heroin-44.7% and 35.9% for methadone vs 15.8% and 21.8% for heroin in 2011 and 2021, respectively. Between 2011 and 2021, most of the drug-related deaths shifted from licit to illicit drugs, and statistically significant variations were found for buprenorphine, cocaine, heroin, methadone, and other licit opioids. Deaths related to polydrug use increased from 23.2% in 2011 to 30.6% in 2021. In this context, opioids remained associated with most deaths, with at least 1 opioid being involved in approximately 9 of 10 cases (85.9%) in 2021. However, the main trend was the dramatic increase in drug combinations with cocaine, from less than one-third of cases in 2011 (30.8%) to more than half in 2021 (57.8%).

Conclusions and Relevance

This case series assessment of 4460 drug-related deaths found that opioids used alone or in combination were the main contributor to drug-related deaths, despite having a lower prevalence than other drugs. This finding is similar to that of other countries; however, in France licit methadone was the leading cause of opioid-related deaths (ahead of heroin) during the study period. Deaths associated with use of cannabis, new psychoactive substances, and stimulants (including amphetamine-type stimulants and cocaine, especially in combination) have increased and should be closely monitored.

Risk-thresholds for the association between frequency of cannabis use and the development of psychosis: a systematic review and meta-analysis

BACKGROUND

Epidemiological studies show a dose-response association between cannabis use and the risk of psychosis. This review aimed to determine whether there are identifiable risk-thresholds between the frequency of cannabis use and psychosis development.

METHODS

Systematic search of Embase, MEDLINE, PsycINFO, CINAHL, and Web of Science for relevant studies (1 January 2010-26 April 2021). Case-control or cohort studies that investigated the relationship between cannabis use and the risk of psychosis development that reported effect estimates [odds ratios (OR), hazard ratios (HR), risk ratios (RR)] or the raw data to calculate them, with information on the frequency of cannabis consumption were included. Effect estimates were extracted from individual studies and converted to RR. Two-stage dose-response multivariable meta-analytic models were utilized and sensitivity analyses conducted. The Newcastle Ottawa Scale was used to assess the risk of bias of included studies.

RESULTS

Ten original (three cohorts, seven case-control) studies were included, including 7390 participants with an age range of 12-65 years. Random-effect model meta-analyses showed a significant log-linear dose-response association between cannabis use frequency and psychosis development. A restricted cubic-splines model provided the best fit for the data, with the risk of psychosis significantly increasing for weekly or more frequent cannabis use [RR = 1.01, 95% confidence interval (CI) 0.93-1.11 yearly; RR = 1.10, 95% CI 0.97-1.25 monthly; RR = 1.35, 95% CI 1.19-1.52 weekly; RR = 1.76, 95% CI 1.47-2.12 daily].

CONCLUSION

Individuals using cannabis frequently are at increased risk of psychosis, with no significant risk associated with less frequent use. Public health prevention messages should convey these risk-thresholds, which should be refined through further work.

"Wake-and-bake" cannabis use: Predictors and cannabis-related outcomes of use shortly after waking

BACKGROUND

Given recent historical increases in young adults frequent cannabis use and changes in cannabis policies throughout the United States, there is a need to examine high-risk patterns of use. This paper examined predictors and cannabis-related outcomes of "wake-and-bake" cannabis use, operationalized as use within 30min of waking.

METHODS

Participants were 409 young adults (Mage=21.61 years, 50.8% female) enrolled in a longitudinal study on simultaneous alcohol and cannabis use (i.e., using alcohol and cannabis at the same time such that their effects overlap). Eligibility criteria included reporting alcohol use 3+ times and simultaneous alcohol and cannabis use 1+ times in the past month. Participants completed twice-daily surveys for six 14-day bursts across two calendar years. Aims were tested using multilevel models.

RESULTS

Analyses were limited to cannabis use days (9406 days; 33.3% of all sampled days), and thereby to participants who reported using cannabis (384 participants; 93.9% of the sample). Wake-and-bake use was reported on 11.2% of cannabis use days and at least once by 35.4% of participants who used cannabis. On wake-and-bake use days, participants were high for more hours and had greater odds of driving under the influence of cannabis, but did not experience more negative consequences, relative to non-wake-and-bake cannabis use days. Participants who reported more cannabis use disorder symptoms and those reporting higher average social anxiety motives for cannabis use reported more frequent wake-and-bake use.

CONCLUSIONS

Wake-and-bake cannabis use may be a useful marker of high-risk cannabis use, including driving under the influence of cannabis.

Understanding feeling "high" and its role in medical cannabis patient outcomes

Introduction: We measure for the first time the associations between subjective patient experiences of feeling "high" and treatment outcomes during real-time Cannabis flower consumption sessions. Methods: Our study uses data from the mobile health app, Releaf App™, through which 1,882 people tracked the effects of Cannabis flower on a multitude of health conditions during 16,480 medical cannabis self-administration sessions recorded between 6/5/2016 and 3/11/2021. Session-level reported information included plant phenotypes, modes of administration, potencies, baseline and post-administration symptom intensity levels, total dose used, and real-time side effect experiences. Results: Patients reported feeling high in 49% of cannabis treatment sessions. Using individual patient-level fixed effects regression models and controlling for plant phenotype, consumption mode, tetrahydrocannabinol (THC) and cannabidiol (CBD) potencies, dose, and starting symptom level, our results show that, as compared to sessions in which individuals did not report feeling high, reporting feeling high was associated with a 7.7% decrease in symptom severity from a mean reduction of -3.82 on a 0 to 10 analog scale (coefficient = -0.295, p < 0.001) with evidence of a 14.4 percentage point increase (p < 0.001) in negative side effect reporting and a 4.4 percentage point (p < 0.01) increase in positive side effect reporting. Tetrahydrocannabinol (THC) levels and dose were the strongest statistical predictors of reporting feeling high, while the use of a vaporizer was the strongest inhibitor of feeling high. In symptom-specific models, the association between feeling high and symptom relief remained for people treating pain (p < 0.001), anxiety (p < 0.001), depression (p < 0.01) and fatigue (p < 0.01), but was insignificant, though still negative, for people treating insomnia. Although gender and pre-app cannabis experience did not appear to affect the relationship between high and symptom relief, the relationship was larger in magnitude and more statistically significant among patients aged 40 or less. Discussion: The study results suggest clinicians and policymakers should be aware that feeling high is associated with improved symptom relief but increased negative side effects, and factors such as mode of consumption, product potency, and dose can be used to adjust treatment outcomes for the individual patient.

Adult use of highly-potent Δ9-THC cannabis concentrate products by U.S. state cannabis legalization status, 2021

BACKGROUND

Compared to plant/flower cannabis products, cannabis concentrates have higher average potency of delta-9-tetrahydrocannabinol (Δ9-THC), which may be associated with greater likelihood of cannabis-related harms. Information on factors associated with use of cannabis concentrates is needed.

METHODS

Respondents were 4,328 adult past-7-day cannabis users from all 50 U.S. states and Washington DC (DC) who participated in an online 2021 survey. Using logistic regression to generate adjusted odds ratios (aOR), we investigated whether participants in states that enacted recreational cannabis laws (RCL, 12 states plus DC [treated as a state], n = 1,236) or medical cannabis laws (MCL-only, 23 states, n = 2,030) by December 31, 2020 were more likely than those in states without cannabis laws (no-CL, 15 states, n = 1,062) to use cannabis concentrate products in the prior 7 days.

RESULTS

Most participants (92.4%) used plant material in the prior 7 days; 57.0% used cannabis concentrates. In RCL, MCL and no-CL states, concentrate use was reported by 61.5%, 56.6%, and 52.5%, respectively. Compared to participants in no-CL states, odds of using cannabis concentrate products were greater among those in RCL states (aOR = 1.47; CI = 1.17-1.84) and MCL-only states (aOR = 1.29; CI = 1.08-1.55). Whether states had legally-authorized dispensaries had little effect on results.

CONCLUSION

Results suggest that individuals in MCL-only and RCL states are more likely to use cannabis concentrate products. Determining mechanisms underlying these results, e.g., commercialization, could provide important information for prevention. Clinicians should be alert to patient use of concentrates, especially in MCL-only and RCL states. Continued monitoring is warranted as additional states legalize cannabis use.

Recommendations for Reducing the Risk of Cannabis Use-Related Adverse Psychosis Outcomes: A Public Mental Health-Oriented Evidence Review

Objective: Cannabis use is increasingly normalized; psychosis is a major adverse health outcome. We reviewed evidence on cannabis use-related risk factors for psychosis outcomes at different stages toward recommendations for risk reduction by individuals involved in cannabis use. Methods: We searched primary databases for pertinent literature/data 2016 onward, principally relying on reviews and high-quality studies which were narratively summarized and quality-graded; recommendations were developed by international expert consensus. Results: Genetic risks, and mental health/substance use problem histories elevate the risks for cannabis-related psychosis. Early age-of-use-onset, frequency-of-use, product composition (i.e., THC potency), use mode and other substance co-use all influence psychosis risks; the protective effects of CBD are uncertain. Continuous cannabis use may adversely affect psychosis-related treatment and medication effects. Risk factor combinations further amplify the odds of adverse psychosis outcomes. Conclusions: Reductions in the identified cannabis-related risks factors-short of abstinence-may decrease risks of related adverse psychosis outcomes, and thereby protect cannabis users' health.

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.

Cannabis-Legalisierung in Deutschland

Zusammenfassung: Zielsetzung: Die deutsche Bundesregierung hat beschlossen, den nicht-medizinischen Cannabis-Gebrauch und -Vertrieb zu legalisieren, und Kernpunkte des vorgesehenen Regelwerks vorgelegt. Einige dieser Kernpunkte werden aus der Sicht internationaler Erfahrungen und wissenschaftlicher Evidenz zur Legalisierung – insbesondere mit Blick auf Massnahmen und Ziele öffentlicher Gesundheit – eingeschätzt und kommentiert. Methodik: Selektive Zusammenfassung und policy-analytische Anwendung wissenschaftlicher Evidenz. Ergebnisse: Ein erheblicher Anteil von Cannabis-bezogenen Gesundheitsproblemen hängt mit dem Konsum von Hochpotenz- (THC) Produkten zusammen; allerdings würden kategorische THC-Grenzwerte für legal verfügbares Cannabis diese im Gesamten wahrscheinlich nicht reduzieren sondern primär Hochrisiko-Konsumenten weiter in der Illegalität belassen. Die Mindestalter-Grenze von 18 Jahren für legales Cannabis macht primär politischen Sinn und repräsentiert nicht unbedingt optimalen Gesundheits- oder sozialen Schutz für junge Konsumenten; allerdings wird der Cannabis-Konsum bei Minderjährigen wahrscheinlich weiter hoch blieben. Eine substanz-übergreifende, gesundheits-orientierte Angleichung mit den Gesetzesregelungen für andere Substanzen (z. B. Alkohol) wäre sinnvoll. Das Fahren unter Cannabis-Einfluss ist relativ häufig, und kann zu Verletzungs- und Todesfällen, und damit erheblicher Gesundheitsbelastung führen; seine Kontrolle braucht gezielte Aufklärungs- und Abschreckungs-Maßnahmen. Cannabis-Legalisierung ist mit einschlägigen internationalen (z. B. UN) Konventionen generell schwierig zu vereinbaren, sollte aber dazu genutzt werden, diese grundsätzlich auf der Basis von Prinzipien des Gesundheitsschutzes zu erneuern. Schlussfolgerungen: Für die Cannabis-Legalisierung in Deutschland gibt es kein perfektes Regelwerk; einige Kern-Ziele werden nur über Kompromiss-Ansätze zu erreichen sein, die im Zweifelsfall angepasst werden müssen. Wenn implementiert, wird Deutschland wichtige Daten zur Cannabis-Legalisierung als Politik-Option bieten können, wozu ein systematisches und umfassendes Prozess- und Ergebnis-Monitoring durchgeführt werden muss.

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.

Cannabis Practices Among a Gender-Diverse Sample of Young Adults

Background

Gender is an important factor in understanding cannabis patterns, yet few studies have explored cannabis patterns among gender minority (GM) individuals - particularly among high-risk age groups including young adults. The evolving cannabis market is reshaping typical patterns of cannabis use in the U.S. The combination of these factors warrants increased efforts to examine cannabis practices in gender-diverse samples.

Methods

Online survey participants between 18-34 years (N=2377) from the U.S. provided information on cannabis practices from May - July 2021. Gender differences across several cannabis outcomes (onset, methods of consumption, product potency, frequency, and quantity) were assessed. Bivariate tests and multiple regression models examined associations between gender (cisgender men: n=1020; cisgender women: n=1178; and GM: n=179) and cannabis outcomes adjusting for sociodemographic characteristics.

Results

In regression models adjusted for sociodemographic characteristics, GM identity was associated with later age of onset and lower likelihood of daily use compared to cisgender men and women. Identifying as GM or cisgender woman was associated with fewer lifetime methods of consumption and lower plant and concentrate potency usage.

Conclusions

Findings provide initial insights into potential gender differences in cannabis practices from a sample of heavy cannabis users. GM young adults report use patterns indicative of lower risk compared to cisgender men and women in our sample. Future investigations of gender differences in cannabis use that explore specific gender minority categories and that include alternative sampling strategies are needed to better understand differential risks associated with gender.

The effects of oral and vaporized cannabis alone, and in combination with alcohol, on driving performance using the STISIM driving simulator: A two-part, double-blind, double-dummy, placebo-controlled, randomized crossover clinical laboratory protocol

The legalization of cannabis for medicinal and non-medicinal purposes, and the corresponding increase in diversity of cannabis products, has resulted an urgent need for cannabis regulatory science. Among the most pressing needs is research related to impairment due to cannabis exposure, especially on driving performance. The present project was designed to evaluate the impact of oral and vaporized cannabis, when administered alone or in combination with alcohol, on simulated driving performance (STISIM driving simulator), cognitive/psychomotor ability, and field sobriety performance. Healthy adults will complete two, double-blind, double-dummy, placebo-controlled, randomized crossover clinical laboratory studies, one with oral cannabis (16 men/16 women) and the second with vaporized cannabis (16 men/16 women). In each study, participants will complete seven experimental sessions during which acute doses of placebo or high Δ9-THC cannabis containing 0, 10, or 25 mg Δ9-THC will be administered both alone and in combination with placebo or alcohol-containing beverages (target breath alcohol concentrations, BAC, of 0.0% or 0.05%). A positive control session (i.e., alcohol at target BAC of 0.08% with placebo cannabis) will also be completed. Simulated driving performance tests (available for download; see Methods), field sobriety assessments, subjective drug effect questionnaires, a mobile device impairment test (DRUID app), and collection of whole blood specimens will be completed repeatedly during each session. Linear mixed models will be used to test for differences across experimental conditions and a priori planned comparisons will be used to determine differences between conditions of interest (e.g., cannabis alone vs cannabis with alcohol). This research is designed to extend prior studies of cannabis and alcohol on driving performance by using oral and vaporized routes of cannabis administration. By increasing understanding of impairment associated with co-use of alcohol and these novel forms of cannabis, this research could inform impairment detection standards for cannabis and alcohol and have important implications for law enforcement, public policy decisions regarding accessibility of these substances, and education of the general population who may use cannabis and/or alcohol. Lastly, this manuscript provides interested researchers with access to the simulated driving scenarios and data extraction tools developed for this study as a means of facilitating future cross-study comparisons, which is important given the heterogeneity in methods used across laboratories in prior research.

Identifying risk-thresholds for the association between frequency of cannabis use and development of cannabis use disorder: A systematic review and meta-analysis

BACKGROUND

Cannabis use disorder (CUD) affects one-in-five cannabis users, presenting a major contributor to cannabis-associated disease burden. Epidemiological data identify the frequency of cannabis use as a risk factor for CUD. This review aimed to determine quantifiable risk-thresholds of the frequency of cannabis use for developing CUD.

METHODS

Systematic search of Medline, EMBASE, PsycInfo, CINAHL, and Web of Science for cohort/case-control studies that assessed the association between frequency of cannabis use and CUD from 2000 to 2022. Effect estimates were converted to risk ratios (RR). A random-effects multi-level multivariate meta-analytic approach was utilized, and sensitivity analyses conducted. Quality of included studies was assessed with the Newcastle Ottawa Scale.

RESULTS

Six prospective cohort studies were included in this review, drawn from two main source studies. Random-effect modeling showed a significant log-linear dose-response association between the frequency of cannabis use and CUD risk (p < 0.0001). The risk of CUD increased from RR:2.03 (95% CI:1.85-2.22) for 'yearly' use, to RR:4.12 (95% CI:3.44-4.95) for 'monthly" use, RR:8.37 (95% CI:6.37-11.00) for 'weekly' use, and RR:16.99 (95% CI:11.80-24.46) for 'daily' use. Multi-level modeling showed an absolute risk increase (ARI) from 3.5% (95% CI:2.6-4.7) for 'yearly' use, to 8.0% (95% CI:5.3-12.1) for 'monthly' use, to 16.8% (95% CI:8.8-32.0) for 'weekly' use, and 36% (95% CI:27.047.9) for 'daily' use.

CONCLUSION

A limited risk of CUD as a potential outcome of cannabis use exists even at infrequent levels of use, but significantly increases as frequency of use increases. Corresponding information should be conveyed to cannabis users as part of targeted prevention messaging to promote safer cannabis use.

The Determination of Cannabinoids in Urine Samples Using Microextraction by Packed Sorbent and Gas Chromatography-Mass Spectrometry

Cannabis is the most consumed illicit drug worldwide, and its legal status is a source of concern. This study proposes a rapid procedure for the simultaneous quantification of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH), cannabidiol (CBD), and cannabinol (CBN) in urine samples. Microextraction by packed sorbent (MEPS) was used to pre-concentrate the analytes, which were detected by gas chromatography–mass spectrometry. The procedure was previously optimized, and the final conditions were: conditioning with 50 µL methanol and 50 µL of water, sample load with two draw–eject cycles, and washing with 310 µL of 0.1% formic acid in water with 5% isopropanol; the elution was made with 35 µL of 0.1% ammonium hydroxide in methanol. This fast extraction procedure allowed quantification in the ranges of 1–400 ng/mL for THC and CBD, 5–400 ng/mL for CBN and 11-OH-THC, and 10–400 ng/mL for THC-COOH with coefficients of determination higher than 0.99. The limits of quantification and detection were between 1 and 10 ng/mL using 0.25 mL of sample. The extraction efficiencies varied between 26 and 85%. This analytical method is the first allowing the for determination of cannabinoids in urine samples using MEPS, a fast, simple, and low-cost alternative to conventional techniques.

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.

Conceptualizing and considering Cannabis-Related "Harm-to-Others": The Role of Cannabis-Related Violence

Public health-oriented frameworks for cannabis use of control, including legalization, are evolving. Most frameworks aim to reduce cannabis-related health harms that materialize among users; there has been comparably limited focus on cannabis-related "harm-to-others". A longstanding issue for other psychoactive substances, and increasingly recognized form of cannabis-related harm-to-others involves violence/aggression. We briefly review relevant epidemiological and psycho-behavioral data related to cannabis-related violence and aggression, and discuss intervention prospects. Systematic review and other study data show a moderately positive association between cannabis use and perpetration of physical (including intimate-partner) violence, for example involving assault, aggression, and fighting; this risk may be further elevated by intensive use patterns. Such harms may involve injuries/deaths and contribute to the cannabis-related burden of disease. Within the contexts of public health-oriented frameworks for cannabis control, greater awareness and targeted interventions regarding the risk for exposure to violence related to cannabis use should be promoted in addition to protections for users' health.

Use of highly-potent cannabis concentrate products: More common in U.S. states with recreational or medical cannabis laws

BACKGROUND

Highly-potent cannabis products, e.g., concentrates, entail greater risks of cannabis-related harms than lower-potency products such as plant or flower material. However, little information is available on whether individuals in U.S. states with recreational cannabis laws (RCL) or medical cannabis laws (MCL) are more likely than individuals in U.S. states without cannabis legalization (no-CL) to use highly-potent forms of cannabis.

METHODS

Cannabis-using adults in a 2017 online survey (N = 4064) provided information on state of residence and past-month cannabis use, including types of products used, categorized as low-potency (smoked or vaped plant cannabis) or high-potency (vaping or dabbing concentrates). Multivariable logistic regression models generated adjusted odds ratios (aOR) and 95% confidence intervals (CI) for use of high-potency cannabis products by state cannabis legalization status (RCL, MCL, no-CL).

RESULTS

Compared to participants in no-CL states, participants in RCL states had greater odds of using high-potency concentrate products (aOR=2.61;CI=1.77-3.86), as did participants in MCL-only states (aOR=1.55;CI=1.21-1.97). When participants in RCL states and MCL states were directly compared, those in RCL states had greater odds of using high-potency concentrate products (aOR=1.69;CI=1.27-2.42).

DISCUSSION

Although the sample was not nationally representative and the cross-sectional data precluded determining the direction of effect, results suggest that use of high-potency cannabis concentrates is more likely among those in RCL states. Clinicians in RCL states should screen cannabis users for harmful patterns of use. Policymakers in states that do not yet have RCL should consider these findings when drafting new cannabis laws, including the specific products permitted and how best to regulate them.

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.