Problems with the identification of 'problematic' cannabis use: examining the issues of frequency, quantity, and drug use environment

Contextual factors associated with subjective effects of cannabis: A systematic review and meta-analysis

BACKGROUND

Cannabis is consumed in various social and environmental settings, and such contexts may be important predictors of subjective effects. The aim of this systematic review and meta-analysis was to examine the relationship between contextual factors and subjective effects of cannabis.

METHODS

A PRISMA-guided search of MEDLINE, Embase, PsycINFO, Global Health, and Google Scholar yielded 29 studies.

RESULTS

Study type (Ecological Momentary Assessment or Experimental) was a significant predictor of intoxication effects, and experimental studies had a greater pooled effect size (z =.296,95% CI [.132,.478], p=.004) than Ecological Momentary Assessment (EMA) studies (z =.071,95% CI [.011,.130], p =.02). Contextual conditions (environment, social group, expectancy, time of day, day of week) were not significant predictors of cannabis effects.

CONCLUSION

Findings did not point to a significant association between contextual conditions and subjective effects. However, as current literature is methodologically weak, it may be premature to conclude that subjective effects are not shaped by contextual factors. In view of policy and therapeutic implications, replications and study refinements are recommended.

Typical Hits, Grams, or Joints: Evaluating Cannabis Survey Measurement Strategies for Quantifying Consumption

Aim: Standardized survey measures that capture diverse cannabis consumption patterns are needed to inform public health and policy. Our team is developing a flexible, personalized, low-burden survey item inventory to measure cannabis use patterns and estimate milligrams of THC (mgTHC) consumption in large samples. This study aimed to identify measurement gaps and analysis implications associated with an initial pool of candidate items that assessed use of cannabis flower and concentrate products (smoked and/or vaporized). Methods: Adult cannabis consumers (n=4247) completed an online survey assessing cannabis use frequency, quantity, product types, product potencies (%THC), and methods of administration. Participants chose to report their consumption quantities using one of three units: "hits per day," "grams per week," or "joints per week." Respondents also indicated whether their past 7-day consumption pattern represented their typical pattern. Results: Eighty-one percent had used cannabis daily in the past week. Thirty-two percent, 53%, and 15% chose to report flower and concentrate consumption quantity in hits, grams, and joints, respectively. Approximately 80-90% of responses for the number of hits, grams, and joints consumed were less than the maximum response option-suggesting that response options captured the full range of potential cannabis consumption behaviors. Those who chose grams or joints units were generally more likely to endorse higher risk cannabis use (e.g., morning use, high %THC products) in the past week than those who chose the hits unit (adjusted Odds Ratio range: 1.2-3.9). Among those who reported that the past week represented their typical behavior (83%), past 30-day and past 7-day frequencies were highly correlated (Spearman's Rho=0.77)-supporting the feasibility of using lower burden "typical week" items to extrapolate patterns beyond a 1-week time frame. Conclusion: Results from this online convenience sample of frequent cannabis consumers suggest that the current items yield coherent and expected response patterns. Although additional testing is required, a standardized, flexible survey instrument for large-scale assessment of cannabis patterns and calculation of mgTHC seems within reach.

Exploring survey methods for measuring consumption quantities of cannabis flower and concentrate products

Background: Researchers need accurate measurements of cannabis consumption quantities to assess risks and benefits. Survey methods for measuring cannabis flower and concentrate quantities remain underdeveloped.Objective: We examined "grams" and "hits" units for measuring flower and concentrate quantities, and calculating milligrams of THC (mgTHC).Methods: Online survey participants (n = 2,381) reported preferred unit (hits or grams), past-week hits and grams for each product, and product %THC. Quantile regression compared mgTHC between unit-preference subgroups. Hits-based mgTHC calculations assumed a universal grams-per-hit ratio (GPHR). To examine individualized GPHRs, we tested a "two-item approach," which divided total grams by total hits, and "one-item approach," which divided 0.5 grams by responses to the question: "How many total hits would it take you to finish 1/2 g of your [product] by [administration method]?"Results: Participants were primarily daily consumers (77%), 50% female sex, mean age 39.0 (SD 16.4), 85% White, 49% employed full-time. Compared to those who preferred the hits unit, those who preferred the grams unit reported consuming more hits and grams, higher %THC products, and consequently, larger median mgTHC (flower-hits mgTHC: 32 vs. 91 (95%CI: 52-67); flower-grams mgTHC: 27 vs. 113 (95%CI: 73-95); concentrate-hits mgTHC: 29 vs. 59 (95%CI: 15-43); concentrate-grams mgTHC: 61 vs. 129 (95%CI: 43-94)). "Two-item" and "one-item" approach GPHRs were similar and frequently 50% larger or smaller than the universal GPHR.Conclusion: Allowing respondents to choose "hits" or "grams" when reporting cannabis quantities does not compromise mgTHC estimates. A low-burden, one-item approach yields individualized "hit sizes" that may improve mgTHC estimates.

Patterns of problematic cannabis use in Canada pre- and post-legalisation: Differences by neighbourhood deprivation, individual socioeconomic factors and race/ethnicity

INTRODUCTION

The legalisation of cannabis in Canada in 2018, and subsequent increase in prevalence of use, has generated interest in understanding potential changes in problematic patterns of use, including by socio-demographic factors such as race/ethnicity and neighbourhood deprivation level.

METHODS

This study used repeat cross-sectional data from three waves of the International Cannabis Policy Study web-based survey. Data were collected from respondents aged 16-65 prior to cannabis legalisation in 2018 (n = 8704), and post-legalisation in 2019 (n = 12,236) and 2020 (n = 12,815). Respondents' postal codes were linked to the INSPQ neighbourhood deprivation index. Multinomial regression models examined differences in problematic use by socio-demographic and socio-economic factors and over time.

RESULTS

No evidence of a change in the proportion of those aged 16-65 in Canada whose cannabis use would be classified as 'high risk' was noted from before cannabis legalisation (2018 = 1.5%) to 12 or 24 months after legalisation (2019 = 1.5%, 2020 = 1.6%; F = 0.17, p = 0.96). Problematic use differed by socio-demographic factors. For example, consumers from the most materially deprived neighbourhoods were more likely to experience 'moderate' vs 'low risk' compared to those living outside deprived neighbourhoods (p < 0.01 for all). Results were mixed for race/ethnicity and comparisons for high risk were limited by small sample sizes for some groups. Differences across subgroups were consistent from 2018 to 2020.

DISCUSSION AND CONCLUSIONS

The risk of problematic cannabis use does not appear to have increased in the 2 years following cannabis legalisation in Canada. Disparities in problematic use persisted, with some racial minority and marginalised groups experiencing higher risk.

Measuring cannabis quantities in online surveys: A rapid review and proposals for ways forward

OBJECTIVES

Cannabis use quantities are relevant for determining cannabis-related harms. This research aims to provide an overview of the available methods to assess quantities through self-report.

METHODS

A rapid review of various strategies to collect information on cannabis use quantities through self-report. Two independent literature searches resulted in n = 38 studies included for review.

RESULTS

A total of n = 14 studies employed methods for collecting cannabis use quantities that are not suitable for online surveys (e.g., rolling a fake joint). Of the remaining n = 24 studies with items that are suitable for online surveys, the quantity assessment was performed in three different ways. The data collection was either carried out by asking (a) for the total number of joints (i.e., crude joint method), (b) for the total weight (i.e., crude weight method), or (c) for specific products separately, for example, for the amount of flower and resin (i.e., product-specific method). In only n = 8 studies, cannabis use quantities were ascertained by providing visual aids (e.g., illustration of various amounts of flower).

CONCLUSIONS

The crude joint method and the product-specific method are the two most promising methods to collect information on cannabis use quantities. Using visual aids may potentially improve the accuracy of those methods.

Changes in Quantity Measures of Various Forms of Cannabis Consumption among Emerging Adults in Canada in Relation to Policy and Public Health Developments

Limited research examines changes in quantities of various forms of smoked/vaped cannabis among regular consumers, including emerging adults (EAs; 18 to 29) in Canada. This information is particularly relevant in the current context of emerging cannabis behaviors among EAs related to political amendments (legalization of cannabis), vaping-related lung illnesses (EVALI), and unprecedented pandemics (COVID-19). This study investigated the impact of legalizing recreational cannabis use in Canada, the EVALI epidemic, and the COVID-19 pandemic on the quantity of smoked/vaped forms of cannabis in relation to gender differences. EAs retrospectively self-reported the quantity of herb, hash, concentrates, joint size, and the number of joints and vaping cartridges in relation to three consecutive developments: pre-legalization, post-legalization; pre-EVALI, post-EVALI, pre-COVID-19, and during COVID-19. The quantity of herb use significantly increased among heavy users, and vaping quantity significantly increased among light users. Overall, an increasing incremental trend was observed in the average quantity of cannabis forms used over time. Males consumed higher quantities of all cannabis forms than females. More males than females reported using concentrates (p < 0.05). These findings reveal unique aspects of the amount of various cannabis forms smoked/vaped in relation to gender and provides preliminary evidence of cannabis consumption behaviors in relation to changing social and cultural contexts.

Evaluating cannabis exposure in survey items: Insights, strategies, and remaining challenges identified from cognitive interviewing

Background

The diversity in characteristics of cannabis products and behavior patterns make evaluation of cannabis exposure in population-based, self-report surveys challenging. Accurate identification of cannabis exposure and related outcomes necessitates a thorough understanding of participants' interpretations of survey questions assessing cannabis consumption behaviors.

Objectives

The current study utilized cognitive interviewing to gain insight on participants' interpretation of items in a self-reported survey instrument used to estimate the quantity of THC consumed in population samples.

Methods

Cognitive interviewing was used to evaluate survey items assessing cannabis use frequency, routes of administration, quantity, potency, and perceived "typical patterns" of use. Ten participants ≥18 years (n = 4 cisgender-men; n = 3 cisgender-women; n = 3 non-binary/transgender) who had used cannabis plant material or concentrates in the past week were recruited to take a self-administered questionnaire and subsequently answer a series of scripted probes regarding survey items.

Results

While most items presented no issues with comprehension, participants identified several areas of ambiguity in question or response item wording or in visual cues included in the survey. Generally, participants with irregular use patterns (i.e., non-daily use) reported more difficulty recalling the time or quantity of cannabis use. Findings resulted in several changes to the updated survey, including updated reference images and new quantity/frequency of use items specific to the route of administration.

Conclusion

Incorporating cognitive interviewing into cannabis measurement development among a sample of knowledgeable cannabis consumers led to improvements in assessing cannabis exposure in population surveys, which may otherwise have been missed.

Induced negative affect's impact on self-reported cannabis use, expectancies, and problems

Substance use disorders and affective disturbances often covary. Even momentary experiences of negative affect (NA) appear linked with substance use. While strong evidence of these relations exists, NA might bias endorsements of substance use due to hindered recall and reporting processes. This hypothesis warrants further research, as accurate assessment of substance-related variables is crucial in both research and treatment settings. The present study examined the influence of NA on reporting of cannabis variables using an affect-induction paradigm. Over 700 individuals recruited from Amazon's MTurk participated. After reporting demographics and baseline affect, participants were randomly assigned to either a NA induction or control condition. Follow-up measures assessed post-induction affect and cannabis-related variables. Results revealed that the NA induction task significantly increased NA and decreased positive affect relative to the control condition. Participants assigned to the NA induction reported greater negative cannabis expectancies and more cannabis problems, even after controlling for age and educational attainment. Cannabis use and cannabis problems appeared positively related. Future research should continue to assess for the influence of NA in reporting of cannabis variables. Should subsequent work find differences in reporting of substance use that appear to covary with negative affect, clinicians and researchers alike should be mindful of the implications of potentially biased reporting on assessment, intervention, and research outcomes.

Adolescent Cannabis Misuse Scale: Longitudinal Associations with Substance Use, Mental Health, and Social Determinants of Health in Early Adulthood

BACKGROUND

Some patterns of cannabis use may presage risk for long-term negative effects. We examined associations between a novel adolescent cannabis misuse scale and early-adult life course outcomes.

METHODS

We performed a secondary data analysis of a cohort of Los Angeles, CA high school students from grade 9 through age 21. Participants reported baseline individual demographic and family characteristics at grade 9, adolescent cannabis misuse (8-items) and alcohol misuse (12-items) at grade 10, and outcomes at age 21. We used multivariable regression to model the associations of cannabis misuse scale score with problem substance use (defined as any of: 30-day illegal drug use, 30-day use of another's prescription to get high, hazardous drinking) and several secondary outcomes (behavioral, mental health, academic, social determinants of health), adjusting for covariates. Parallel analyses were conducted for alcohol misuse.

RESULTS

The 1,148 participants (86% retention) were 47% male, 90% Latinx, 87% US born, and 40% native English speakers. Approximately 11.4% and 15.9% of participants reported at least one item on the cannabis and alcohol misuse scales, respectively. At age 21, approximately 6.7% of participants reported problem substance use, which was associated with both Cannabis and Alcohol Misuse Scales (OR 1.31, 95%CI[1.16, 1.49] and OR 1.33, 95%CI[1.18, 1.49], respectively). Both scales were similarly associated with outcomes in all four categories.

CONCLUSIONS

The Adolescent Cannabis Misuse Scale is a promising tool for identifying early patterns of substance use that predict future negative outcomes and enabling early intervention at a critical period in youth development.

"I feel like marijuana is the only drug that wouldn't kill me": perceptions of cannabis use in previously incarcerated Black men who have sex with other men

BACKGROUND

Fragmented state laws have impacted cannabis uptake and perceptions in the USA. Little research has explored the attitudes, beliefs, and social network influences of young Black men who have sex with men (BMSM) who have experienced incarceration and use cannabis. While problematic cannabis use is not well defined and understudied, scholars have found that a person's social network can mediate problematic substance use and reduce recidivism rates by providing both tangible and emotional support. This analysis examines how social networks contribute to cannabis perceptions and use among BMSM with criminal legal system involvement in Chicago, IL, and Houston TX.

METHODS

Researchers conducted interviews with 25 cis gender Black men informed by life course theory, with a focus on the role of social networks, incarceration, and other life experiences in substance use. All interviews were audio-recorded, de-identified, and transcribed; participants were compensated $50. A deductive-inductive thematic analysis was used to analyze all qualitative data collected.

RESULTS

Twelve BMSM in Chicago and 13 BMSM in Houston (M = 26.6 years old, SD = 3.7) were interviewed. A majority identified as gay (56%), with 12 participants (48%) reporting having a high school diploma or equivalent; their average age of first substance use was 15.2 (SD = 2.9). Participants perceived cannabis usage to be categorically distinct from other intoxicating substance usage, with many describing it as not harmful and potentially beneficial. Three themes shaped their choices and attitudes regarding cannabis and "hard" drugs-social networks, need fulfillment, and knowledge of risk.

CONCLUSION

Participant descriptions of cannabis use emphasize their drug-use behavior as being produced by agent decision-making and risk assessment. Future work should expand on how these decisions are made, and how social networks can be leveraged to encourage non-harmful drug consumption behaviors.

Development of scales to measure Lebanese university students’ perceived knowledge about and attitudes about cannabis use: initial psychometric properties

Background

For a long period, cannabis in Lebanon was categorized as an illegal psychoactive substance criminalized by law, despite being the 3rd largest producer of cannabis resin after Morocco and Afghanistan. The current available literature on the topic in Lebanon is scarce, as perceived knowledge towards cannabis use in the general population is not well established, and public health policies are absent. In the context of future legalization of cannabis for both medical and recreational purposes, what is the public’s perception of cannabis perceived knowledge about and attitude against cannabis use? The objectives of this study were to create two scales to assess perceived knowledge towards cannabis use and attitude against cannabis use and check their psychometric properties in a sample of Lebanese university students.

Methods

The study was designed as a cross-sectional study involving 415 Lebanese university students aged between 18 and 30 years. Students were only recruited from one university and were sent an email with a brief description of the study and a link to the questionnaire. The questionnaire items covered perceived knowledge and attitude about cannabis use, recovered and adapted from available literature.

Results

Perceived knowledge items converged over a solution of four factors that had an Eigenvalue over 1, explaining a total of 64% of the variance (factor 1 = perceived knowledge about cannabis quality of life improvement; factor 2 = perceived knowledge about cannabis psychiatric use; factor 3 = perceived knowledge about cannabis risks; factor 4 = perceived knowledge about cannabis neurological use). Attitude items converged over a solution of two factors that had an Eigenvalue over 1, explaining a total of 58.2% of the variance (factor 1 = negative attitude about cannabis use; factor 2 = positive attitude about cannabis use). Good Cronbach’s alpha values were found for the perceived knowledge and attitude scales (α = 0.78 and α = 0.73 respectively). Greater perceived knowledge was found in male participants and in those who have tried cannabis for recreational purposes. Greater perceived knowledge was also associated with stronger attitude about cannabis use and older age. Furthermore, greater mean attitude about cannabis use scores were significantly found in male participants and in those who have tried cannabis for recreational or medicinal purposes.

Conclusion

Primary results showed acceptable psychometric properties for the perceived knowledge towards and attitudes about cannabis use scale. Further studies are needed in order to validate them among the general population and assess more psychometric properties of these scales.

The association between recreational cannabis use and posttraumatic stress disorder: A systematic review and methodological critique of the literature

BACKGROUND

Given recent changes in the legal status of cannabis, the risks and benefits associated with its use have become an important public health topic. A growing body of research has demonstrated that posttraumatic stress disorder (PTSD) and recreational cannabis use (RCU) frequently co-occur, yet findings are inconsistent (e.g., direction of effect) and methodological variability makes comparison across studies difficult.

METHODS

We conducted a comprehensive systematic review of all studies (N = 45) published before May 2020 regarding etiologic models of co-occurring RCU and PTSD, as well as provided a methodological critique to inform suggestions for future research initiatives.

RESULTS

Findings indicate that a majority of studies (n = 37) demonstrated a significant association between RCU and PTSD. Findings provide evidence for the self-medication and high-risk models posited to explain co-occurring RCU and PTSD despite variability in assessment of RCU, which includes commonly used non-standardized self-report questions.

CONCLUSION

The association between RCU and PTSD is likely bidirectional. Results inform clinicians and researchers working in the mental health and cannabis use fields how the variability in findings on the association between RCU and PTSD may be attributable, in part, to methodological issues that permeate the extant literature pertaining to RCU and PTSD.

Typologies of Canadian young adults who drive after cannabis use: A two-step cluster analysis

Young adults that drive after cannabis use (DACU) may not share all the same characteristics. This study aimed to identify typologies of Canadians who engage in DACU. About 910 cannabis users with a driver's license (17-35 years old) who have engaged in DACU completed an online questionnaire. Two-step cluster analysis identified four subgroups, based on driving-related behaviors, cannabis use and related problems, and psychological distress. Complementary comparative analysis among the identified subgroups was performed as external validation. The identified subgroups were: (1) frequent cannabis users who regularly DACU; (2) individuals with generalized deviance with diverse risky road behaviors and high levels of psychological distress; (3) alcohol and drug-impaired drivers who were also heavy frequent drinkers; and (4) well-adjusted youths with mild depressive-anxious symptoms. Individuals who engaged in DACU were not a homogenous group. When required, prevention and treatment need to be tailored according to the different profiles.

Measuring recent cannabis use across modes of delivery: Development and validation of the Cannabis Engagement Assessment

•

The CEA is consistent with expert-recommended guidelines for quantifying cannabis use.

•

The CEA is representative of current patterns of recreational cannabis engagement.

•

Estimates of cannabis use show strong associations with the timeline followback method.

•

The CEA shows good test–retest reliability over a one-week period.

Introduction

Methods of cannabis engagement have proliferated in recent years, which many self-report measures do not adequately capture. There is a clear need for self-report measures that capture current patterns of cannabis use across a range of methods, and that can be used to track changes over time. The current study developed the Cannabis Engagement Assessment (CEA), a self-report measure of past month cannabis use across dry flower, concentrate, and edible products.

Methods

A sample of 349 participants from the undergraduate student population and broader community were recruited. To examine convergent validity of the CEA, participants completed measures of cannabis engagement, cannabis misuse, and use-related problems. To assess divergent validity, participants also completed measures of depression and alcohol use problems. Criterion and test–retest reliability were examined in a subset of 65 participants who re-completed the CEA and a timeline follow-back interview (TLFB).

Results

Indicators of cannabis use frequency and quantity showed good convergence with measures of cannabis use patterns, problematic engagement, and cannabis use-related problems. Divergent validity of the CEA was supported by lower associations with alcohol use problems and depression symptoms. The CEA also showed good test–retest reliability and convergence with estimates of frequency and quantity of cannabis use from the TLFB.

Conclusions

The CEA is a viable self-report measure of cannabis use that is representative of current patterns of recreational cannabis engagement. Its focus on cannabis use in the preceding 30 days also lends itself to measuring changes in use over time.

Reactivity to Daily Self-Monitoring of Cannabis Use in Biological Females

Assessment reactivity involves changes to behaviours from self-monitoring those behaviours (Nelson & Hayes, 1981). In the substance use field, reactivity has been identified both as a potential confound in daily diary research (Cohn et al., 2015) and as a possible intervention tool in clinical practice (Cohn et al., 2018). Reactivity to daily self-monitoring of alcohol and tobacco use has been inconsistent in prior research. Reactivity to daily self-monitoring of cannabis use quantity has received far less study. This study involved secondary analyses of data from N = 88 females who self-monitored their cannabis use for 32 days. We examined objective reactivity of cannabis use to daily self-monitoring by assessing changes in daily cannabis use over 32 days. We also explored participants' perceptions of the impact daily self-monitoring had on their cannabis use at study completion (i.e., subjective reactivity). In hurdle models testing objective reactivity, neither probability of cannabis use, nor quantity of cannabis use, changed significantly over the study period. Many respondents (45%) reported no subjective reactivity, though a slight majority (55%) reported some subjective reactivity. Subjective reactivity did not moderate objective reactivity over time; however, higher subjective reactivity was significantly associated with increased variability (interquartile range [IQR]) in cannabis use across the self-monitoring period. Overall, reactivity appears unlikely to confound research utilizing daily diary cannabis measures, and daily self-monitoring of cannabis use may be unlikely to serve as a useful stand-alone intervention for reducing cannabis use in non-treatment-seeking individuals. Potential clinical implications of the novel finding of a link between subjective reactivity and objective cannabis use variability are discussed.

Non-abstinent treatment outcomes for cannabis use disorder

BACKGROUND

Abstinence remains a standard outcome for potential treatment interventions for Cannabis Use Disorder (CUD). However, there needs to be validation of non-abstinent outcomes. This study explores reductions in self-reported days of use as another viable outcome measure using data from three completed randomized placebo-controlled clinical trials of pharmacological interventions for CUD.

METHODS

The three trials tested the effect of quetiapine (QTP, n = 113); dronabinol (DRO, n = 156); and lofexidine + dronabinol (LFD, n = 122). Self-reported cannabis use was categorized into three use-groups/week: heavy (5-7 days/week), moderate (2-4 days/week) and light use (0-1 days/week). Multinomial logistic regressions analyzed the treatment by time effect on the likelihood of light and moderate use compared to heavy use in each study.

RESULTS

Across the three trials, there was no significant overall time-by-treatment interaction (QTP: p = .06; DRO: p = .15; LFD: p = .21). However, the odds of moderate compared to heavy use were significantly higher in treatment than in placebo groups starting around the midpoint of each trial. No treatment differences were found between the odds of light compared to heavy use.

CONCLUSIONS

While study-end abstinence rates have been a standard treatment outcome for CUD trials, reduction from heavy to moderate use has not been standardly assessed. During the last several weeks of each trial, those on active medication were more likely to move from heavy to moderate use, which suggests that certain medications may be more impactful than previously assessed. Future studies should determine if this pattern is associated with less CUD severity and/or improved quality of life.

Cannabis based medicines and cannabis dependence: A critical review of issues and evidence

Cannabis has been legalised for medical use in an ever-increasing number of countries. A growing body of scientific evidence supports the use of medical cannabis for a range of therapeutic indications. In parallel with these developments, concerns have been expressed by many prescribers that increased use will lead to patients developing cannabis use disorder. Cannabis use disorder has been widely studied in recreational users, and these findings have often been projected onto patients using medical cannabis. However, studies exploring medical cannabis dependence are scarce and the appropriate methodology to measure this construct is uncertain. This article provides a narrative review of the current research to discern if, how and to what extent, concerns about problems of dependence in recreational cannabis users apply to prescribed medical users. We focus on the main issues related to medical cannabis and dependence, including the importance of dose, potency, cannabinoid content, pharmacokinetics and route of administration, frequency of use, as well as set and setting. Medical and recreational cannabis use differs in significant ways, highlighting the challenges of extrapolating findings from the recreational cannabis literature. There are many questions about the potential for medical cannabis use to lead to dependence. It is therefore imperative to address these questions in order to be able to minimise harms of medical cannabis use. We draw out seven recommendations for increasing the safety of medical cannabis prescribing. We hope that the present review contributes to answering some of the key questions surrounding medical cannabis dependence.

Problematic substance use or problematic substance use policies?

This special issue on substance use issues comes at a critical time for Canadian health policy makers and researchers. Most attention is currently focussed on the opioid crisis and the potential impacts of cannabis legalization. However, our most widely used and harmful substances continue to be alcohol and nicotine. Our policies to reduce harms from these substances are failing. While alcohol control policies are being gradually abandoned, opportunities to maximize the harm reduction potential of new, alternative and safer nicotine delivery devices are not being grasped. More generally, a greater focus is needed on harm reduction strategies that are informed by the experience of marginalized people with severe substance use-related problems so as to not exacerbate health inequities. In order to better inform policy responses, we recommend innovative approaches to monitoring and surveillance that maximize the use of multiple data sources, such as those used in the Canadian Substance Use Costs and Harms (CSUCH) project. Greater attention to precision in defining patterns of risky use and harms is also needed to support policies that more accurately reflect and respond to actual levels of substance use-related harm in Canadian society.

College students' using marijuana to sleep relates to frequency, problematic use, and sleep problems

OBJECTIVE

Given the rising rates of insufficient sleep and the popularity of marijuana, we investigated using marijuana as a sleep aid, marijuana use frequency, problematic marijuana use, and sleep problems. Participants: Participants included a convenience sample of college students who endorsed using marijuana in the past year from May to December 2013 (N = 354; 68% female, 57% White). Methods: Path analyses investigated if using marijuana to sleep predicted: (1) marijuana use outcomes and (2) sleep problems; and if sleep problems predicted marijuana use outcomes. Results: Using marijuana to sleep was related to increased use and problematic use, as well as worse sleep efficiency. Daytime dysfunction related to sleepiness was associated with elevated levels of marijuana use and problematic use. Similar associations were found across sex and race. Conclusions: College students should be informed of the potential misconceptions between marijuana and improved sleep and provided with evidence-based alternatives to improve their sleep.

Neurodevelopmental Effects of Cannabis Use in Adolescents and Emerging Adults with ADHD: A Systematic Review

OBJECTIVE

Systematically review the scientific literature to characterize the effects of cannabis use on brain structure, function, and neurodevelopmental outcomes in adolescents and young adults with ADHD.

METHOD

Systematic review following PRISMA guidelines utilizing PubMed, Embase, PsycINFO, and Cochrane CENTRAL trials register from inception until 1 January 2020. Articles that examined the impact of cannabis use on youth with ADHD were included.

RESULTS

Eleven studies were identified that compared outcomes for individuals with ADHD who used cannabis or synthetic cannabinoids against those with ADHD who did not. Seven of these studies used neuroimaging techniques, including fMRI, structural MRI, and SPECT. Differential regions of activation were identified, including the right hippocampus and cerebellar vermis, and bilateral temporal lobes. Morphological differences were identified in the right precentral and postcentral gyri, left nucleus accumbens, right superior frontal and postcentral gyri. No study identified any additive or ADHD × cannabis use interaction on neuropsychological tasks of executive function. Two studies found adverse differential impacts of early-onset cannabis use in this population.

CONCLUSION

A dearth of evidence is available on the impact of cannabis use on the developing brain and functioning for individuals with ADHD, despite the elevated risk for substance use in this population. The limited, potentially underpowered evidence does not support the hypothesis that cannabis use has a deleterious impact on neuropsychological tasks in transitional age youth with ADHD. Larger and longer-term studies are needed, however, to better inform clinicians and patients as to the impacts of cannabis use in youth with ADHD.

Cannabis use and bariatric surgery psychology practice: survey and insights

BACKGROUND

Cannabis is second only to alcohol as a substance of abuse and dependence in the United States. While there is extensive research examining alcohol use and bariatric surgery, there is currently little research and there are no published guidelines specific to cannabis use and bariatric surgery.

OBJECTIVES

To identify major themes and general guidelines applied by bariatric surgery psychology clinicians.

SETTING

This practice survey was disseminated to bariatric surgery psychologists at various U.S. academic medical centers, hospitals, and private practices.

METHODS

An electronic, 35-question survey was sent to 47 bariatric surgery psychologists to collect information on current clinical practice guidelines regarding cannabis use before and after bariatric surgery.

RESULTS

The survey questionnaire was completed by 34 (72.34%) bariatric surgery psychologists. The major identified themes included: (1) the lack of a standardized assessment of cannabis use; (2) a requirement for 3 months of abstinence from cannabis before bariatric surgery; (3) recommended lifetime abstinence from cannabis after bariatric surgery; and (4) discussion of cannabis use risks following bariatric surgery, including appetite stimulation, addiction potential, and possible negative impacts on judgment.

CONCLUSION

Cannabis use will likely further increase in the United States. This survey highlighted common bariatric surgery psychology practices in the absence of extensive research and published guidelines. These findings suggest a preliminary framework with which to address cannabis use in patients seeking bariatric surgery. It is recommended that professional organizations and societies build on these initial survey findings to develop guidelines for more consistent, evidence-based practice regarding cannabis use and bariatric surgery.

Quantity and frequency of cannabis use in relation to cannabis-use disorder and cannabis-related problems

BACKGROUND

In almost all of the literature examining the relation between cannabis use and cannabis-related harms, researchers have neglected to include quantity measures of cannabis use. The study aims to assess whether cannabis: (1) quantity predicts harms; and (2) quantity might interact with other key variables (age, gender, and frequency of use) vis-à-vis the outcomes.

METHOD

Using the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions-III (NESARC-III), the current study (n = 36,309; n = 3,339 past-year cannabis users) employed a logistic-regression approach to assess the cross-sectional relations between the continuous variables of cannabis-use quantity and frequency and two Alcohol Use Disorder and Associated Disabilities Interview Schedule-5 (AUDADIS-5) DSM-5-based outcomes: past-year cannabis-use disorder (CUD) and past-year cannabis-related problems (CRP).

RESULTS

In the CUD model, the key variables log quantity [OR = 1.98 (95 % CI, 1.64;2.39), p < 0.001], log frequency [OR = 1.78 (95 % CI, 1.62;1.96), p < 0.001] and the log-quantity-by-log-frequency interaction [OR = 0.83 (95 % CI, 0.75;0.93), p = 0.002] were statistically significant. The final CRP model included the following main predictors: log quantity [OR = 2.13 (95 % CI, 1.70;2.66), p = <0.001], log frequency [OR = 1.50 (95 % CI, 1.36;1.65), p = <0.001], and a log-quantity-by-log-frequency interaction [OR = 0.82 (95 % CI, 0.73;0.93), p = 0.002].

CONCLUSIONS

The quantity-by-frequency interactions in both models showed that the relative effect of quantity on cannabis-use disorders and cannabis-related problems decreased as frequency increased, and vice versa.

Self-isolation: A significant contributor to cannabis use during the COVID-19 pandemic

BACKGROUND

Emerging research suggests the COVID-19 pandemic has resulted in a significant increase in self-reported isolation and loneliness in a large proportion of the population. This is particularly concerning given that isolation and loneliness are associated with increased cannabis use, as well as using cannabis to cope with negative affect. Objective: We investigated whether self-isolation due to COVID-19 and using cannabis to cope with depression were unique and/or interactive predictors of cannabis use during the pandemic, after controlling for pre-pandemic levels of cannabis use. Method: A sample of 70 emerging adults (mean age = 23.03; 34.3% male) who used both alcohol and cannabis pre-pandemic completed measures of cannabis use (i.e., quantity x frequency) and a novel COVID-19 questionnaire between March 23 and June 15, 2020. Pre-pandemic cannabis use levels had been collected four months earlier. Results: Linear regressions indicated self-isolation and coping with depression motives for cannabis use during the pandemic were significant predictors of pandemic cannabis use levels after accounting for pre-pandemic use levels. There was no interaction between coping with depression motives and self-isolation on cannabis use during the pandemic. Conclusions: Those who engaged in self-isolation were found to use 20% more cannabis during the pandemic than those who did not. Our results suggest that self-isolation is a unique risk factor for escalating cannabis use levels during the pandemic. Thus, self-isolation may inadvertently lead to adverse public health consequences in the form of increased cannabis use.

Situating the Continuum of Overdose Risk in the Social Determinants of Health: A New Conceptual Framework

Policy Points This article reconceptualizes our understanding of the opioid epidemic and proposes six strategies that address the epidemic's social roots. In order to successfully reduce drug-related mortality over the long term, policymakers and public health leaders should develop partnerships with people who use drugs, incorporate harm reduction interventions, and reverse decades of drug criminalization policies.

CONTEXT

Drug overdose is the leading cause of injury-related death in the United States. Synthetic opioids, predominantly illicit fentanyl and its analogs, surpassed prescription opioids and heroin in associated mortality rates in 2016. Unfortunately, interventions fail to fully address the current wave of the opioid epidemic and often omit the voices of people with lived experiences regarding drug use. Every overdose death is a culmination of a long series of policy failures and lost opportunities for harm reduction.

METHODS

In this article, we conducted a scoping review of the opioid literature to propose a novel framework designed to foreground social determinants more directly into our understanding of this national emergency. The "continuum of overdose risk" framework is our synthesis of the global evidence base and is grounded in contemporary theories, models, and policies that have been successfully applied both domestically and internationally.

FINDINGS

De-escalating overdose risk in the long term will require scaling up innovative and comprehensive solutions that have been designed through partnerships with people who use drugs and are rooted in harm reduction.

CONCLUSIONS

Without recognizing the full drug-use continuum and the role of social determinants, the current responses to drug overdose will continue to aggravate the problem they are trying to solve.

Cannabis health knowledge and risk perceptions among Canadian youth and young adults

Abstract

Background

Although recreational cannabis is now legal in Canada, little empirical evidence exists regarding young Canadians’ cannabis literacy, cannabis-related risk perceptions, and risk of different forms of cannabis or the effect that public health education may have on these perceptions. The present study sought to address these knowledge gaps to examine health knowledge and risk perceptions associated with cannabis use.

Methods

An online survey was conducted with a national sample (N = 870) of Canadians aged 16 to 30 years in October 2017 using a commercial panel. The study examined young Canadians’ awareness of negative health effects related to cannabis, evaluation of known risks, and risk perceptions of different forms of administration.

Results

Most respondents were aware of a cannabis-related physical health effect (78.0%). Approximately one-third reported having been exposed to public health messaging about cannabis; digital media was reported most frequently. Compared to never users, ever users were less likely to report general likelihood of addiction (p < 0.001) and harm to mental health (p < 0.001). Approximately one-quarter of past 3-month cannabis users reported they were at least “a little” addicted. Respondents who reported using a particular form of cannabis self-administration (e.g., edibles, smokables) were less likely to perceive harm than those who did not use each form (p < 0.001).

Conclusions

The current study is among the first to measure the knowledge and perceptions of risks of Canadian youth about cannabis. The study, conducted in the time immediately preceding legalization, may serve as a reference point for future studies examining changes in cannabis knowledge and risk perceptions. This will be important in addressing the need for monitoring and enhancing public awareness of the impact and potential harms of this newly legalized substance.

The Intersection between Spliff Usage, Tobacco Smoking, and Having the First Joint after Waking

Cannabis users who are also tobacco smokers are more likely to exhibit cannabis dependence and psychosocial problems. However, there has been minimal research around various cannabis and tobacco mixing (spliff usage) behaviours and likeliness to smoke the first joint within an hour of waking, known colloquially as wake and bake. The time of first joint and spliff usage may be related as they are associated with the intersection of tobacco and cannabis use. Compared to non-morning cannabis users, morning users reported significantly more cannabis-related problems. Through a survey of US cannabis users, we test the association between various cannabis and spliff use behaviours and likeliness to smoke the first joint within an hour of waking. Compared to those who smoked tobacco and used spliffs, the following spliff use behaviour groups were less likely to have their first joint within 60 minutes after waking: those who smoked tobacco and used spliffs (95%CI: 0.605-0.988); those who never smoked tobacco and did not use spliffs (95%CI: 0.489-0.892); those who never smoked tobacco and used spliffs (95%CI:0.022-0.915). We provided possible explanations for our results and suggested further research to better understand findings, important given expanding US cannabis markets.

Patterns and correlates of cannabis use by cumulative lifetime violence severity as target and/or perpetrator in a community sample of eastern Canadian men

Background

Recent Canadian legalization of cannabis for non-medical use underscores the need to understand patterns and correlates of cannabis use among men who may be more likely than women to become problematic cannabis users. Evidence supporting an association between substance use and violence is accumulating. Current knowledge of relationships among patterns of cannabis use, violence, gender and health is limited by dichotomous measurement of cannabis use and a focus on individual types of violence rather than lifetime cumulative violence.

Methods

We collected online survey data between April 2016 and Septermber 2017 from a community convenience sample of 589 Eastern Canadian men ages 19 to 65 years and explored how socio-demographic characteristics, gender, and health varied by past-year patterns of cannabis use (i.e., daily, sometimes, never) in the total sample and by higher and lower cumulative lifetime violence severity (CLVS) measured by a 64-item CLVS scale score (1 to 4).

Results

Overall prevalence of cannabis use was 46.6% and differed significantly between lower (38.1%) and higher (55.3%) CLVS groups (χ² (1) = 17.42, p = .000). Daily cannabis use was more likely in the higher (25.1%) than the lower group (11.9%, χ² (2) = 31.53, p < .001). In the total sample, daily use was significantly associated with being single, less education, lower income, some gender norms, health problems, and use of other substances. Significant associations were found for sometimes cannabis use with age group 19 to 24 years, being single, some gender norms, and hazardous and binge drinking. Never use was associated with being married, more education, higher income, being older, not using other substances, and not having mental health problems. Associations between cannabis use patterns and many variables were found in both CLVS groups but effect sizes were frequently larger in the higher group.

Conclusions

These results add substantively to knowledge of relationships among lifetime cumulative violence, patterns of cannabis use, gender, socio-demographic indicators and health problems and may inform theoretical models for future testing. Additionally, findings provide critical information for the design of health promotion strategies targeted towards those most at risk in the current climate of cannabis legalization.

Systematic Review of Cannabis Use and Risk of Occupational Injury

Aim: A range of nations, including countries of the European Union, Australia, and the Americas have recently implemented or proposed reforms to how they control cannabis use, thereby departing from traditional approaches of criminal prohibition that have dominated throughout most of the twentieth century. Given these policy developments and the widespread global use of cannabis, it is critically important to understand the possible risks associated with cannabis use in relation to major societal harms. Methods: This systematic review investigates the potential link between cannabis use and occupational injury. Consequently, it appraises all available current literature from five databases, following Cochrane and PRISMA guidelines. Results: Seven of the 16 reviewed studies show evidence supporting a positive association between cannabis use and occupational injury. One study shows evidence supporting a negative association and the remaining eight studies show no evidence of a significant relation. None of the studies assessed cannabis-related impairment. Only three of the reviewed studies show clear evidence that cannabis use preceded the occupational-injury event. Conclusion: The current body of evidence does not provide sufficient evidence to support the position that cannabis users are at increased risk of occupational injury. Further, the study quality assessment suggests significant biases in the extant literature are present due to potential confounding variables, selection of participants, and measurement of exposures and outcomes. Future high-quality evidence will be needed to elucidate the relation between cannabis use and occupational injury.

Definition of a 'standard joint equivalent': Comment on "Who consumes most of the cannabis in Canada? Profiles of cannabis consumption by quantity"

Using Canadian survey data, Callaghan and colleagues examined the distribution of cannabis quantities after converting reported quantities of different cannabis products into standard joint equivalents. We argue that the assumed amount of 0.5 g dried cannabis flowers unlikely represents a usual dose in average consumers. Moreover, some conversion factors are implausible with regard to the THC concentration levels in select products. As with standard drinks, standard joint equivalents should be consistent with potency, i.e. THC concentration, and should be lower than suggested by the authors.

Problems with defining cannabis dependence

PURPOSE OF REVIEW

Cannabis enjoys a unique social status, widely perceived as a relatively harmless drug, with several benefits reported by the people who use it. Several jurisdictions have opened up access to cannabis to their populations for medicinal and/or recreational reasons. Given this changing regulatory environment, this article is intended to prompt debate about what is known about cannabis dependence and what has still to be revealed.

RECENT FINDINGS

Evidence suggests that 1 in 10 cannabis users are at risk of developing dependence. However, investigation of the way risk is estimated and the diagnosis of cannabis use disorder is constructed highlight some methodological problems, which call into question the incidence and prevalence of this diagnosis.

SUMMARY

There is scope to improve the way cannabis dependence is defined and counted in at-risk populations. Improving our understanding of this risk could lead to identifying who might be at risk of developing dependence prior to exposure to the drug.

Who consumes most of the cannabis in Canada? Profiles of cannabis consumption by quantity

AIM

To establish whether the population-level pattern of cannabis use by quantity is similar to the distributions previously reported for alcohol, in which a small subset of drinkers accounts for a majority of total population alcohol consumption.

METHOD

The current study pooled Waves 1-3 of the 2018 National Cannabis Survey (n = 18,900; 2584 past-three-month cannabis users), a set of stratified, population-based surveys designed to assess cannabis consumption and related behaviors in Canada. Each survey systematically measured self-reported cannabis consumption by quantity across seven of the major cannabis-product types. In order to enable the conversion of self-reported consumption of non-flower cannabis products into a standard joint equivalent (SJE: equal to 0.5 g of dried cannabis), we created conversion metrics for physical production equivalencies across cannabis products.

RESULTS

Similar to the findings in the alcohol literature, study results show that cannabis consumption is highly concentrated in a small subset of users: the upper 10% of cannabis users accounted for approximately two-thirds of all cannabis consumed in the country. Males reported consuming more cannabis by volume than females (approximately 60% versus 40%), with young males (15-34 years old) being disproportionately represented in the heaviest-using subgroups.

CONCLUSIONS

Most of the cannabis used in Canada is consumed by a relatively small population of very heavy cannabis users. Future research should attempt to identify the characteristics of the heaviest-using groups, as well as how population-level cannabis consumption patterns relate to the calculus of cannabis-related harms in society.

Modes of cannabis use: A secondary analysis of an intensive longitudinal natural history study

INTRODUCTION

There is a paucity of research on modes of cannabis use (e.g., joint vs. blunt), and further, little consensus on how to accurately assess both modes of use and route of administration. This secondary analysis used a longitudinal design with data collected daily to characterize mode of cannabis use.

METHODS

193 adult daily cannabis users who were considering quitting at some point enrolled in the study. No treatment was provided. Each day for 84 days, participants reported on mode of cannabis use (i.e., joints, blunts, pipes/vaporizer and food) using an interactive voice response system. We report on single and poly-use of modes across study days and weeks and examine characteristics associated with different modes of use.

RESULTS

White participants were most likely to use pipes/vaporizer, with use on 57% of study days, while Black participants were most likely to use blunts with use on 53% of days. Thus, joint use was less common in both groups. Poly-use of different modes within the same week was very common (i.e., 56% of weeks among White participants and 60% of weeks in Black participants). Age, gender, race, cannabis dependence, presence of others during cannabis use, and alcohol use were associated with different modes of use.

CONCLUSIONS

The major limitation of this study was use of a convenience sample and lack of detailed data on vaporizer use. Joint use is no longer the most common mode of use in either White or Black participants and exclusive use of a single modality is uncommon.

Risk and protective factors for transgender youths' substance use

Research at the intersection of substance use and protective factors among transgender youth is scarce; emerging evidence suggests high risk for substance use for transgender youth. We analyzed data from 323 transgender youth aged 14–18 (M_age = 16.67) to investigate the extent that risk (enacted stigma) and protective factors (support from family, school, friends) were related to substance use (i.e., cannabis and tobacco use, binge drinking). Enacted stigma was linked to higher odds of substance use behaviors, family connectedness was related to lower levels of tobacco and cannabis use, and more than one protective factor significantly lowered the probability of engaging in substance use behaviors. Support from multiple sources may be differentially protective against substance use for transgender youth.

•

Risk and protective factors are strongly related to substance use among transgender youth.

•

Differing combinations illustrate the importance of social support in reducing substance use.

•

High enacted stigma is linked to higher odds of substance use among transgender youth.

•

More than one protective factor lowers the probability of engaging in substance use.

Marijuana use associated with worse verbal learning and delayed recall in a sample of young adults

BACKGROUND

There is concern about the cognitive consequences of marijuana consumption.

AIM

To assess the influence of current and past marijuana use and frequency on verbal learning and memory in a sample of adults aged 21 years old.

MATERIAL AND METHODS

Marijuana use was assessed using a clinician administered interview in 654 participants (56% females), who reported frequency of use, age of first use and whether its use led to problems in their lives. The CogState International Shopping List was administered to assess learning and memory.

RESULTS

Seventy percent reported ever using marijuana, 46% consuming during the past year and 27% during the past 30 days. The latter scored significantly lower on delayed recall. Current and frequent use were significantly associated with lower accuracy in verbal learning and memory.

CONCLUSIONS

In this cohort of adults aged 21 years old, marijuana use was prevalent and related to worse verbal memory.

Early Risk Factors for Daily Cannabis Use in Young Adults

OBJECTIVES

Daily cannabis use can portend problematic use or dependence. We aimed to identify early risk factors for daily cannabis use in young adults.

METHODS

Data were available in a longitudinal investigation of 1294 grade 7 students age 12 to 13 years at inception recruited in 10 secondary schools in Montreal, Canada, in 1999. Data on daily cannabis use were collected in mailed self-report questionnaires from 878 participants (67.9% of 1294) at age 20. The associations between each of 23 potential risk factors measured in grade 7 and daily cannabis use at age 20 were modeled using logistic regression.

RESULTS

At age 20, 44% of participants reported past-year cannabis use; 10% reported daily use. Older age; male sex; higher levels of family stress and other stress; use of alcohol, cigarettes, and other tobacco products; parent(s), sibling(s), and friend(s) smoke cigarettes; higher body mass index; higher impulsivity and novelty seeking; and lower self-esteem increased the odds of daily cannabis use.

CONCLUSIONS

Children at risk of daily cannabis use as young adults can be identified early. They may benefit from early intervention to prevent problematic cannabis use.

Differentiating the Drug Normalization Framework: A Quantitative Assessment of Cannabis Use Patterns, Accessibility, and Acceptability Attitudes among University Undergraduates

BACKGROUND/OBJECTIVES

The drug normalization framework investigates the social integration of substance use. This article contributes a quantitative assessment of cannabis normalization as differentiated by social location predictors.

METHODS

Logistic and zero-inflated negative binomial regression models assess three areas of cannabis normalization: accessibility, acceptability, and recent use. Peer network cannabis use prevalence, gender, nativity, campus locale and living arrangement are explored as focal predictors of variation in normalization among 1,713 cannabis using and nonusing undergraduate students in Canada.

RESULTS

Women report lower odds of positive cannabis acceptability attitudes. While women report lower rates of recent cannabis use, gender is not a significant predictor for lifetime prevalence. Being a recent immigrant significantly predicts lower recent use, lower odds of favorable attitudes to cannabis, and reduced accessibility in comparison to students born in Canada. Longer-term immigrants do not show significant differences from students born in Canada on accessibility and acceptability, suggesting a substance use acculturation effect. Lower peer cannabis use prevalence exhibits a protective effect against use. In comparison to students who report that "some" of their peer network uses cannabis, those with "all" users in their network exhibit lower acceptability attitudes. This suggests a threshold relationship between peer use prevalence and acceptability. Conclusions/Importance: This article provides a data point for assessing future shifts in cannabis normalization prior to impending changes in Canadian drug policy that will legalize recreational cannabis use. Results show that normalization components of recent use, acceptability, and accessibility are differentiated by gender, nativity, and peer network cannabis use prevalence.

Does social context matter? An ecological momentary assessment study of marijuana use among college students

INTRODUCTION

Past research has shown that marijuana use occurs commonly in social situations for young adults, though few studies have examined the association between immediate social context and marijuana use patterns and associated problems. The current study examined the impact of demographics, marijuana use and problem use, alcohol use, craving, and social context on the likelihood of using marijuana with others via ecological momentary assessment (EMA).

METHODS

College-student marijuana users (N=56) were recruited and completed a baseline assessment and training on the two-week signal-contingent EMA protocol. Participants were sent text messages three times per day randomly for two weeks.

RESULTS

Of the 1131 EMA instances during which participants reported using marijuana, 862 (76.22%) were labeled as being with others. Forty-five participants (80.36%) reported marijuana use with others present during at least half of the times they used marijuana. Findings from a multilevel logistic regression model showed a significant positive association between the probability of using with others and minutes spent using marijuana (b=0.047, p<0.001), social facilitation (b=0.138, p<0.001), and DSM-IV diagnosis (dependence versus no diagnosis, b=1.350, p=0.047).

CONCLUSIONS

Cannabis dependence, more time using marijuana in the moment, and using for social facilitation purposes were positively associated with using marijuana in the context of being with others. Daily users had more variability in terms of the social context of their use. This study illustrates the complex relationship between social context and marijuana use.

Quantifying cannabis: A field study of marijuana quantity estimation

The assessment of marijuana use quantity poses unique challenges. These challenges have limited research efforts on quantity assessments. However, quantity estimates are critical to detecting associations between marijuana use and outcomes. We examined accuracy of marijuana users' estimations of quantities of marijuana they prepared to ingest and predictors of both how much was prepared for a single dose and the degree of (in)accuracy of participants' estimates. We recruited a sample of 128 regular-to-heavy marijuana users for a field study wherein they prepared and estimated quantities of marijuana flower in a joint or a bowl as well as marijuana concentrate using a dab tool. The vast majority of participants overestimated the quantity of marijuana that they used in their preparations. We failed to find robust predictors of estimation accuracy. Self-reported quantity estimates are inaccurate, which has implications for studying the link between quantity and marijuana use outcomes. (PsycINFO Database Record

Medical Marijuana and Marijuana Legalization

State-level marijuana liberalization policies have been evolving for the past five decades, and yet the overall scientific evidence of the impact of these policies is widely believed to be inconclusive. In this review we summarize some of the key limitations of the studies evaluating the effects of decriminalization and medical marijuana laws on marijuana use, highlighting their inconsistencies in terms of the heterogeneity of policies, the timing of the evaluations, and the measures of use being considered. We suggest that the heterogeneity in the responsiveness of different populations to particular laws is important for interpreting the mixed findings from the literature, and we highlight the limitations of the existing literature in providing clear insights into the probable effects of marijuana legalization.

Rethinking indicators of problematic cannabis use in the era of medical cannabis legalization

INTRODUCTION

Recent rapid changes in medical cannabis policies and increases in medical use of cannabis have raised new research questions related to potential effects of medical cannabis legalization on cannabis use problems. In order to investigate such effects there is a need for screening tools that are sensitive to the fact that people may be using for medical and/or recreational purposes. This article critically assesses whether screening tools designed to measure cannabis use problems in recreational users are meaningful as measures of problems resulting from medical use.

RESULTS AND CONCLUSIONS

It is possible that existing cannabis problem screening tools are not equally valid across medical and recreational users, since individual screening items have different implications for recreational and medical users. For instance, items that measure use that deviates from common patterns of recreational use (use before midday and use alone) reflect normative assumptions that non-problematic recreational use will occur in contexts of parties or social gatherings. However, use before midday and alone are how people typically take medication for chronic medical health problems. There is thus a need to develop and validate criteria for problematic use in medical cannabis patients.

The Cannabis Abuse Screening Test (CAST) revisited: examining measurement invariance by age

Defensible use of self-reported cannabis use problem scales in age comparative frameworks requires that measured constructs have equal psychometric properties across age groups. This study compares the psychometric properties of the Cannabis Abuse Screening Test (CAST) across three age groups (18-24, 25-29, 30-40). Data was collected online from an accessible sample of 1316 cannabis users. Factor analysis compared the optimal factor structure and dimensionality diffraction. Multi-group Model Invariance tests examined measurement invariance across the three age groups. CAST was two-dimensional in all age groups with one factor measuring cannabis use problems and the other measuring deviation from a common standard of use. The two-dimensional structure was more pronounced in older age groups. Weak factorial invariance was supported, suggesting that the meaning of the CAST factors is equivalent across age groups. Partial, but not full, strong factorial invariance was supported, indicating that only the cannabis use problem factor can be defensibly used to measure age group mean differences. Results confirm a well-defined two-dimensional CAST structure and factorial invariance across age groups. However, caution is needed when using the two items measuring deviation from a common standard in an age-comparative framework. Replication studies based on a representative sample are needed.

Past year cannabis use and problematic cannabis use among adults by ethnicity in Ontario

BACKGROUND

Rates of cannabis use differ around the world; in Ontario, the rate of use has been stable since about 2005. Understanding which population groups are at greater risk for problematic cannabis use can help reduce long-term health effects and service expenses. The aim of this study was to explore differences in cannabis use among Canadian adults of different ethnic origins living in Ontario.

METHODS

Data are based on telephone interviews with 11,560 respondents and are derived from multiple cycles (2005-2011) of the Centre for Addiction and Mental Health's (CAMH) Monitor survey, an ongoing cross-sectional survey of adults in Ontario, Canada, aged 18 years and older. Data were analyzed using bivariate cross-tabulations and logistic regression. Problematic cannabis use was determined with a score of 8+ on the ASSIST-CIS to identify moderate/high problematic users.

RESULTS

Lifetime, past year and problematic cannabis use (in the past 3 months) occurs among all ethnic groups: Canadian, East Asian, South East Asian, South Asian, Caribbean, African, East European, South European, North European, and Central West European. When compared to the Canadian group the odds of past year cannabis use was significantly lower for East Asians and South Asians, but higher for the Caribbean group. Significantly higher odds of problematic cannabis use were found for Caribbeans and Northern Europeans compared to Canadians.

CONCLUSIONS

These results of this study provide an important basis for considering the possible impact of the impending legalization of cannabis in Canada among different ethnic groups.

Therapeutic use of cannabis: Prevalence and characteristics among adults in Ontario, Canada

OBJECTIVE

To investigate the prevalence of therapeutic cannabis use within a general population sample of adults and to describe various characteristics associated with use.

METHODS

Data were derived from the 2013 and 2014 CAMH Monitor Survey of adults in Ontario, Canada. This repeated cross-sectional survey employed a regionally stratified design and utilized computer-assisted telephone interviewing. Analyses were based on 401 respondents who reported using cannabis.

RESULTS

The data indicated that 28.8% of those who used cannabis in the past year self-reported using cannabis for therapeutic purposes. Of therapeutic users, 15.2% reported having medical approval to use cannabis for therapeutic purposes. Cannabis use for therapeutic purposes was associated with more frequent use of cannabis, a moderate to high risk of problematic cannabis use, and a greater likelihood of using prescription opioids for medical purposes. There was little difference in cannabis use for therapeutic purposes according to sex, age, and marital status after adjusting for opioid use and problematic cannabis use.

CONCLUSION

Findings suggest some potential negative consequences of cannabis use for therapeutic purposes; however, further research is needed to better understand the range and patterns of use and their corresponding vulnerabilities.

The Standard Joint Unit

OBJECTIVE

Reliable data on cannabis quantities is required to improve assessment of cannabis consumption for epidemiological analysis and clinical assessment, consequently a Standard Joint Unit (SJU) based on quantity of 9-Tetrahydrocannabinol (9-THC) has been established.

METHODOLOGY

Naturalistic study of a convenience sample recruited from February 2015-June 2016 in universities, leisure spaces, mental health services and cannabis clubs in Barcelona. Adults, reporting cannabis use in the last 60 days, without cognitive impairment or language barriers, answered a questionnaire on cannabis use and were asked to donate a joint to further determine their 9-THC and Cannabidiol (CBD) content.

RESULTS

492 participants donated 315 valid joints. Donators were on average 29 years old, mostly men (77%), single (75%), with at least secondary studies (73%) and in active employment (63%). Marijuana joints (N=232) contained a median of 6.56mg of 9-THC (Interquartile range-IQR=10,22) and 0.02mg of CBD (IQR=0.02); hashish joints (N=83) a median of 7.94mg of 9-THC (IQR=10,61) and 3.24mg of CBD (IQR=3.21). Participants rolled 4 joints per gram of cannabis and paid 5€ per gram (median values).

CONCLUSION

Consistent 9-THC-content in joints lead to a SJU of 7mg of 9-THC, the integer number closest to the median values shared by both cannabis types. Independently if marijuana or hashish, 1 SJU = 1 joint = 0.25 g of cannabis = 7 mg of 9-THC. For CBD, only hashish SJU contained relevant levels. Similarly to the Standard Drink Unit for alcohol, the SJU is useful for clinical, epidemiological and research purposes.

Patterns and factors of problematic marijuana use in the Canadian population: Evidence from three cross-sectional surveys

OBJECTIVES

The objectives of this study are to describe marijuana use in Canada and explore factors associated with problematic use.

METHODS

Data from the 2010-2012 circulations of the Canadian Alcohol and Drug Use Monitoring Survey were used to create three logistic regression models for the purposes of identifying and comparing factors associated with the degree of marijuana use, as determined via the WHO Alcohol, Smoking and Substance Abuse Involvement Screening Test (non-problematic, problematic) and European Monitoring Centre for Drugs and Drug Addiction (experiential, recent, current) methods.

RESULTS

Canadians aged 15-24 years are 15 times (p < 0.001) more likely to be current users than Canadians aged 65 or older, with the odds of exhibiting problematic marijuana use being 10 times (p < 0.001) greater. The odds of a male exhibiting problematic marijuana use are 2.46 times (p < 0.001) greater than for females. The odds of exhibiting problematic marijuana use are 41.0% (p = 0.031) and 53.0% (p = 0.008) greater for marijuana users with household incomes $40,000-$80,000 and less than $40,000 respectively compared to those with household income over $80,000. An earlier age of first marijuana use is associated with problematic use but not necessarily with being a current user.

CONCLUSION

The majority of our findings are consistent with the literature, showing that Canadians who are: male, adolescent or young adult, smokers, heavy drinkers, other illicit drug users, and who have poorer mental health status are more likely to engage in any marijuana use, particularly higher levels of marijuana use. These findings can be used to inform the development of policy in Canada to address problematic marijuana use and prepare for its possible legalization.

Measuring cannabis consumption: Psychometric properties of the Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Inventory (DFAQ-CU)

OBJECTIVE

We created the Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Inventory (DFAQ-CU) because the current lack of psychometrically sound inventories for measuring these dimensions of cannabis use has impeded research on the effects of cannabis in humans.

METHOD

A sample of 2,062 cannabis users completed the DFAQ-CU and was used to assess the DFAQ-CU's factor structure and reliability. To assess validity, a subsample of 645 participants completed additional measures of cannabis dependence and problems (Marijuana Smoking History Questionnaire [MSHQ], Timeline Followback [TLFB], Cannabis Abuse Screening Test [CAST], Cannabis Use Disorders Identification Test Revised [CUDIT-R], Cannabis Use Problems Identification Test [CUPIT], and Alcohol Use Disorder Identification Test [AUDIT]).

RESULTS

A six-factor structure was revealed, with factors measuring: daily sessions, frequency, age of onset, marijuana quantity, cannabis concentrate quantity, and edibles quantity. The factors were reliable, with Cronbach's alpha coefficients ranging from .69 (daily sessions) to .95 (frequency). Results further provided evidence for the factors' convergent (MSHQ, TLFB), predictive (CAST, CUDIT-R, CUPIT), and discriminant validity (AUDIT).

CONCLUSIONS

The DFAQ-CU is the first psychometrically sound inventory for measuring frequency, age of onset, and quantity of cannabis use. It contains pictures of marijuana to facilitate the measurement of quantity of marijuana used, as well as questions to assess the use of different forms of cannabis (e.g., concentrates, edibles), methods of administering cannabis (e.g., joints, hand pipes, vaporizers), and typical THC levels. As such, the DFAQ-CU should help facilitate research on frequency, quantity, and age of onset of cannabis use.

Measuring cannabis consumption: Psychometric properties of the Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Inventory (DFAQ-CU)

Objective

We created the Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use Inventory (DFAQ-CU) because the current lack of psychometrically sound inventories for measuring these dimensions of cannabis use has impeded research on the effects of cannabis in humans.

Method

A sample of 2,062 cannabis users completed the DFAQ-CU and was used to assess the DFAQ-CU’s factor structure and reliability. To assess validity, a subsample of 645 participants completed additional measures of cannabis dependence and problems (Marijuana Smoking History Questionnaire [MSHQ], Timeline Followback [TLFB], Cannabis Abuse Screening Test [CAST], Cannabis Use Disorders Identification Test Revised [CUDIT-R], Cannabis Use Problems Identification Test [CUPIT], and Alcohol Use Disorder Identification Test [AUDIT]).

Results

A six-factor structure was revealed, with factors measuring: daily sessions, frequency, age of onset, marijuana quantity, cannabis concentrate quantity, and edibles quantity. The factors were reliable, with Cronbach’s alpha coefficients ranging from .69 (daily sessions) to .95 (frequency). Results further provided evidence for the factors’ convergent (MSHQ, TLFB), predictive (CAST, CUDIT-R, CUPIT), and discriminant validity (AUDIT).

Conclusions

The DFAQ-CU is the first psychometrically sound inventory for measuring frequency, age of onset, and quantity of cannabis use. It contains pictures of marijuana to facilitate the measurement of quantity of marijuana used, as well as questions to assess the use of different forms of cannabis (e.g., concentrates, edibles), methods of administering cannabis (e.g., joints, hand pipes, vaporizers), and typical THC levels. As such, the DFAQ-CU should help facilitate research on frequency, quantity, and age of onset of cannabis use.