Cannabis Consumption, Purchasing and Sources among Young Canadians: The Cannabis Purchase and Consumption Tool (CPCT)

A qualitative study of experiences among young adults who increased their cannabis use during the COVID-19 pandemic

BACKGROUND

Young adults face unique vulnerabilities during major life disruptions like the COVID-19 pandemic. The pandemic contributed to increases in mental health challenges and substance use among young adults. This study explores the experiences of young adults who increased their cannabis use during the pandemic.

METHODS

Participants were recruited from the Nicotine Dependence in Teens (NDIT) study, and qualitative data were collected through semi-structured interviews conducted via Zoom. A total of 25 participants (ages 33-34) reporting increased cannabis use during the pandemic were included. Thematic analysis and gender-based analysis was employed to extract key themes.

RESULTS

Five themes emerged: (1) No disruption in cannabis use; (2) Cannabis use to manage declines in mental health; (3) Cannabis use to break up pandemic boredom; (4) Cannabis use as an expression of freedom; (5) Cannabis use as "another way to chill out."

CONCLUSIONS

This research provides valuable perspectives on how major life disruptions, like the COVID-19 pandemic, influence cannabis use among young adults. The findings offer guidance for public health initiatives and highlight avenues for further investigation.

Prenatal ethanol and cannabis exposure have sex- and region-specific effects on somatostatin and neuropeptide Y interneurons in the rat hippocampus

BACKGROUND

Cannabis is increasingly being legalized and socially accepted around the world and is often used with alcohol in social settings. We recently showed that in utero exposure to both substances can alter the density of parvalbumin-expressing interneurons in the hippocampus. Here we investigate the effects of in utero alcohol and cannabis exposure, alone or in combination, on somatostatin- and neuropeptide Y-positive (NPY) interneurons. These are separate classes of interneurons important for network synchrony and inhibition in the hippocampus.

METHODS

A 2 (Ethanol, Air) × 2 (tetrahydrocannabinol [THC], Vehicle) design was used to expose pregnant Sprague-Dawley rats to either ethanol or air, in addition to either THC or the inhalant vehicle solution, during gestational days 5-20. Immunohistochemistry for somatostatin- and NPY-positive interneurons was performed in 50 μm tissue sections obtained at postnatal day 70.

RESULTS

Exposure to THC in utero had region-specific and sex-specific effects on the density of somatostatin-positive interneurons in the adult rat hippocampus. A female-specific decrease in NPY interneuron cell density was observed in the CA1 region following THC exposure. Combined exposure to alcohol and THC reduced NPY neurons selectively in the ventral dentate gyrus hippocampal subfield. However, overall, co-exposure to alcohol and cannabis had neither additive nor synergistic effects on interneuron populations in other areas of the hippocampus.

CONCLUSIONS

These results illustrate how alcohol and cannabis exposure in utero may affect hippocampal function by altering inhibitory processes in a sex-specific manner.

Individual differences in legal and illicit cannabis purchasing behaviour in British Columbia, Canada: Findings from a 2021 cross-sectional survey

BACKGROUND

Despite thousands of licensed cannabis retail stores operating across Canada, there remains a significant illicit cannabis market. Some cannabis users continue to buy cannabis from dealers, illicit stores, and/or illicit online retailers.

METHODS

Data are from the 2021 British Columbia Cannabis Use Survey. Respondents (n = 8473) were 19 years or older, lived in British Columbia at the time of the survey, and reported using cannabis in the past 12 months.

RESULTS

Buying cannabis from all types of illicit sources was more common among younger cannabis users, those who use cannabis more frequently and started using cannabis before the age of 17 (vs. 19 or older), and among those who co-use cannabis with other drugs. Specifically, buying cannabis from a dealer was more common among men, those with lower educational attainment, and those who seek the lowest prices when buying cannabis. In contrast, those using cannabis for medical (vs. non-medical) purposes were more likely to report getting cannabis from illicit retail stores, while buying cannabis from illicit websites was more common among people who use edible cannabis products.

CONCLUSION

Consistent with other studies, younger and more frequent cannabis users were more likely to report buying cannabis from illicit sources. However, these findings suggest there is significant heterogeneity among those who buy cannabis from different types of illicit sources, which should be carefully considered when developing policies and strategies aimed at encouraging consumers to transition to legal sources.

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.

Estimating THC Consumption from Smoked and Vaped Cannabis Products in an Online Survey of Adults Who Use Cannabis

Introduction: Quantification of consumption patterns of the primary psychoactive compounds in cannabis, which cause euphoria or intoxication, is sorely needed to identify potential risks and benefits of use and to provide meaningful safety information to the public. The diversity of products available, multiple methods of administration, and lack of labeling of products have made such quantification challenging. Our group is developing a survey instrument for estimating the quantity of delta 9-tetrahydrocannabinol (THC) consumed in population samples, which is flexible and incorporates individualized reports of patterns of consumption. This study provides an illustration of a procedure for translating self-reported consumption into milligrams of THC (mgTHC), which may serve as a working model for future quantification efforts. Methods: Social media advertising was leveraged to enroll 5627 adults who use cannabis into an online, anonymous survey study. Only those who used cannabis in the past 7 days, used flower or concentrate products, and who chose to report their quantity of use in hits per day or grams per week (n=3211) were included in this report. Formulas were used to estimate mgTHC used per day, in hits per day or grams per week; potency (%THC); constants for estimating the amount of material consumed for each hit; and a method of administration efficiency constant to account for THC loss due to the administration method. Results: The estimate for mgTHC used per day was M=92.8 mg/day (SD=97.2 mg; 1st-3rd quartile range=25-132 mg). The estimated quantity of use was much lower for those reporting in hits (M=43.7 mg, SD=43.8) than for those reporting in grams (M=115.1 mg, SD=107.0). The estimated rate of binge use in the past week, arbitrarily defined as more than 50 mgTHC within any one daily time quadrant, was 6.8%, which increased to 29.3% if 25 mgTHC was used. Conclusions: The approach illustrated in this study goes beyond existing cannabis measures by asking participants to provide highly detailed estimates of their past 7-day use patterns and then applying a logical formula to translate this information into mgTHC. This initial procedure has limitations and lacks generalization; however, we hope this demonstration stimulates testing of similar approaches and relevant laboratory experiments that will enhance the validity of cannabis consumption estimation procedures.

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.

Knowledge of Cannabinoid Content Among People Living with HIV Who Use Cannabis: a Daily Diary Study

BACKGROUND

Many people living with HIV (PLWH) use cannabis for medicinal reasons. Patients' knowledge of the tetrahydrocannabinol (THC) and cannabidiol (CBD) concentrations of the cannabis products they use may be important in helping patients achieve symptom relief while guarding against potential risks of cannabis use. However, no studies have examined cannabinoid concentration knowledge among PLWH.

METHOD

PLWH (N = 29; 76% men, mean age 47 years) reporting cannabis use for both medicinal and nonmedicinal reasons completed daily surveys over 14 days assessing cannabis products used, knowledge of cannabinoid concentrations of cannabis products used, cannabis use motives (medicinal, nonmedicinal, both), and positive and negative cannabis-related consequences. Across the 361 cannabis use days captured on the daily surveys, at least some knowledge of cannabinoid concentrations was reported on an average of 43.1% (for THC) and 26.6% (for CBD) of the days.

RESULTS

Generalized linear mixed models revealed that participants were more likely to report knowing THC and CBD concentrations on days when they used non-flower forms of cannabis relative to days when they used cannabis flower only. Participants who used cannabis for medicinal reasons on a greater proportion of days had greater knowledge of cannabinoid concentration overall across days. Further, greater overall knowledge of cannabinoid concentrations was associated with fewer reported negative cannabis-related consequences.

CONCLUSIONS

Findings suggest that among PLWH, knowledge of cannabinoid concentrations may be higher when using non-flower cannabis products and among those reporting primarily medicinal cannabis use. Moreover, knowledge of cannabinoid concentration may protect against negative cannabis-related consequences in this population.

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.

Topical Cannabidiol (CBD) After Total Knee Arthroplasty Does Not Decrease Pain or Opioid Use: A Prospective Randomized Double-Blinded Placebo-Controlled Trial

BACKGROUND

Multimodal analgesia has become the standard of care for pain management following total knee arthroplasty (TKA). Cannabidiol (CBD) is increasingly utilized in the postoperative period. The purpose of this study was to analyze the analgesic benefits of topical CBD following primary TKA.

METHODS

In this randomized double-blinded placebo-controlled trial, 80 patients undergoing primary unilateral TKA applied topical CBD (CBD; n = 19), essential oil (EO; n = 21), CBD and essential oil (CBD + EO; n = 21), or placebo (PLA; n = 19) thrice daily around the knee for two weeks postoperatively. This supplemented a standardized multimodal analgesic protocol. Outcomes included visual analog scale (VAS) pain and numeric rating scale (NRS) sleep scores (collected on postoperative day [POD] 0, 1, 2, 7, 14, 42), and cumulative postoperative opioid use (42 days).

RESULTS

Demographic characteristics were similar among the four cohorts. Preoperative VAS and NRS scores were similar among groups. The CBD cohort had a higher mean VAS pain score on POD 2 compared to the EO cohort (CBD: 69.9 ± 19.3 versus. EO: 51.0 ± 18.2; P = .013). No statistically significant differences existed for VAS scores at other times, and no statistically significant differences were observed for postoperative NRS sleep scores or postoperative opioid use at any time point.

CONCLUSION

Utilization of topical CBD in supplement to multimodal analgesia did not reduce pain or opioid consumption, or improve sleep scores following TKA. These results suggest that the local effects of topical CBD are not beneficial for providing additional pain relief after TKA.

Cannabis edibles packaging: Communicative objects in a growing market

BACKGROUND

Cannabis edibles were legalized for recreational use across Canada in October 2019. The Canadian Cannabis Act requires legally produced edibles to be sold in plain single-color packages with limited branded elements and prominent health warning labels, serving size and nutritional information, and product ingredients including amounts of cannabis compounds. Little research, however, assesses what consumers think of standardized packaging, and how product packaging influences perceptions of cannabis edibles.

METHODS

Eight focus groups with young adults (ages 18-24; n = 57) were conducted in November 2018. Participants were recruited from a Canadian university, and asked to assess sample images of cannabis packaging approved by Health Canada. They then discussed the information they would like to see on packages. Focus group discussions were transcribed and analyzed using a descriptive, qualitative approach following methods of process evaluation and inductive coding.

RESULTS

Discussions generally pertained to four main themes: dosage and consumption recommendations; food and nutritional information; concerns for children; and health warning labels. Participants suggested improvements for cannabis packaging, including standardized THC units, non-numerical consumption instructions, and unit-dose packaging. Instead of recommending packaging that deters consumption, participants requested packaging features that promote safe consumption by adults while also protecting children. Findings reveal how packages function as communicative objects that convey meanings about safety and risk, yet these meanings may not resonate with Canadian young adults' perceptions of cannabis as relatively safe.

CONCLUSIONS

While the packaging regulated for use in Canada may be assumed, due to its plain, standardized format, to communicate "little", we highlight tensions in the meanings of such packaging to young adults-especially around competing ideas related to safety and risk.

A Survey of Topical Cannabis Use in Canada

BACKGROUND

Since its legalization in Canada, cannabis use has expanded to include commercially available topical formations. Several scientifically unsupported claims regarding the therapeutic efficacy of topical cannabis are also being made. Developing an understanding of the consumer uses of topical cannabis is important for clinicians to provide appropriate counseling and inform potential areas of therapeutic development. We are examining the prevalence, purpose of use, and sources of information regarding topical cannabis in the Canadian population, with a focus on dermatologic uses.

METHOD

A cross-sectional, anonymous electronic, voluntary survey was developed to assess the use of topical cannabis amongst adults in Canada.

RESULTS

Cannabis was used topically at least once by 24.3% of respondents who started the survey. The commonest form of topical cannabis were creams (26.2%). The most common dermatologic conditions being treated with topical cannabis included atopic dermatitis (25%), acne (19%), and anti-aging (16%); for non-dermatologic conditions, common uses were for joint stiffness or tendonitis (30%) and headaches and migraines (27%). Topical cannabis was reported to be most effective for joint stiffness and tendonitis, general muscular soreness, headaches, eczema, pruritus, acne, and psoriasis. Most respondents obtained and received information about topical cannabis from dispensaries.

CONCLUSION

Canadians use topical cannabis for a broad range of systemic and dermatologic purposes, most of which have limited evidence. Future clinical studies are required to elucidate the therapeutic efficacy and safety of topical cannabis. Dermatologists should screen their patients for topical cannabis use and be aware of the limited evidence of therapeutic potential.

Noticing of cannabis health warning labels in Canada and the US

INTRODUCTION

Product labelling and health warnings are important components of regulatory frameworks for consumer products such as tobacco, alcohol and food. However, evidence in the cannabis domain is limited. This study aimed to examine the reach of mandated health warnings on cannabis products using a natural experimental design.

METHODS

Data are from the online International Cannabis Policy Study 2018 and 2019 surveys. Respondents were men and women aged 16 to 65 years in Canada and US states with illegal and legal nonmedical cannabis ("illegal" and "legal" states, respectively) (n = 72 549). Regression models tested differences in noticing health warnings on cannabis packages pre- and post-legalization in Canada, with comparisons to US states, adjusting for cannabis use, cannabis source and sociodemographics.

RESULTS

Respondents in Canada showed a greater increase in noticing warnings (+8.9%) in 2019 (14.7%) versus 2018 (5.8%) than respondents in US "illegal" states (+2.8%) and "legal" states (+3.2%). In 2019, consumers residing in jurisdictions with legal recreational cannabis who purchased from legal retail sources were more likely to report noticing warnings than consumers who obtained cannabis from illegal/unstated sources (Canada: 40.4% vs. 15.3%; US "legal" states: 35.3% vs. 17.0%). Regular cannabis consumers were more likely to notice warnings than less frequent consumers.

CONCLUSION

Mandating warning labels on cannabis products may increase exposure to messages communicating the health risks of cannabis, especially among frequent consumers and those who access the legal market.