Behavioral economic interactions between cannabis and alcohol purchasing: Associations with disordered use

Utility of a brief measure of cannabis demand: Day-level associations with cannabis use

BACKGROUND

Cannabis demand (i.e., relative value) is usually assessed as a trait-level risk-factor for cannabis use and consequences. This study examined within-person variability in day-level intensity (i.e., amount consumed at zero cost) and Omax (i.e., maximum cannabis expenditure) and tested hypotheses that demand would be positively associated with day-level cannabis use.

METHODS

Young adults (n=85) reporting past-month simultaneous alcohol and cannabis use completed two daily surveys for 30 days. Morning surveys assessed prior-day cannabis use and evening surveys assessed day-level demand (i.e., intensity, Omax). Multilevel models tested day-level effects of intensity and Omax on any cannabis use and flower use frequency and quantity (i.e., grams).

RESULTS

Approximately 52 % and 46 % of variability in intensity and Omax, respectively, was due to within-person change. At the day-level, higher intensity and Omax were associated with higher likelihood of any cannabis use, regardless of formulation; Omax was associated with use of flower in particular; and intensity was associated with the highest quantity of use. At the person-level, only Omax was associated with flower use likelihood, and only intensity was associated with flower quantity across days.

CONCLUSIONS

Cannabis demand demonstrated day-to-day variability, conceivably in response to various internal states and external factors. Intensity and Omax were related to elevated likelihood of using any cannabis, particularly flower, at the day-level. Overall, these data illustrate the validity and utility of brief cannabis demand measures, which might be used to further understand cannabis' reinforcing value at a fine-grained level.

Lessons Learned in Developing a Behavioral Economic Measure of Cannabis Use Using a Predominantly White Sample

Behavioral economic approaches to measuring cannabis demand represent a well-validated, low-cost method of assessing risk for hazardous cannabis use. One widely used measure of cannabis demand is the Marijuana Purchase Task (MPT), which has shown good psychometric properties across multiple samples. However, preliminary data suggest that changes could improve task ecological validity and acceptability. Using a predominantly White convenience sample, this study aimed to develop a revised MPT that uses a modern dispensary scenario to better reflect national trends in cannabis use (e.g., multiple forms of cannabis consumption). Participant inattentiveness due to increased task length and difficulty estimating purchases for the next month may have impacted demand measures. Lessons learned are discussed to inform future efforts to assess cannabis demand in a manner that is more reflective of naturalistic use: including minimizing participant burden, setting higher price ceilings to increase task utility, and considering person-level factors that may influence demand.

Simultaneous Cannabis and Alcohol Use among Medical Cannabis Patients

Background: During the past two decades of cannabis legalization, the prevalence of medical cannabis (MC) use has increased and there has also been an upward trend in alcohol consumption. As less restricted cannabis laws generate more adult cannabis users, there is concern that more individuals may be simultaneously using medical cannabis with alcohol. A few studies have examined simultaneous use of medical cannabis with alcohol, but none of those studies also assessed patients' current or previous non-medical cannabis use. This paper explores simultaneous alcohol and medical cannabis use among medical cannabis patients with a specific focus on previous history of cannabis use and current non-medical cannabis use. Methods: A retrospective cohort study of MC patients (N = 319) from four dispensaries located in New York. Bivariate chi-square tests and multivariable logistic regression are used to estimate the extent to which sociodemographic and other factors were associated with simultaneous use. Results: Approximately 29% of the sample engaged in simultaneous use and a large share of these users report previous (44%) or current (66%) use of cannabis for non-medical purposes. MC patients who either previously or currently use cannabis non-medicinally, men, and patients using MC to treat a pain-related condition, were significantly more likely to report simultaneous alcohol/MC use. Conclusions: Findings indicate that there may be differential risks related to alcohol/MC use, which should be considered by cannabis regulatory policies and prevention/treatment programs. If patients are using cannabis and/or alcohol to manage pain, clinicians should screen for both alcohol and cannabis use risk factors.

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.

Behavioral economic relationship between cannabis flower and concentrates: Evidence from simulated purchase tasks

Cannabis users use different forms of cannabis, which are associated with distinct public health concerns. Policies that aim to regulate one specific form may have unintended impacts on other forms. This study examined the behavioral economic relationship between flower and concentrates, the two most common forms of cannabis. We surveyed 605 adult cannabis users (21+) who lived in one of the U.S. states that had legalized recreational cannabis by the time of interview in 2019. The participants completed simulated purchase tasks, which asked how much cannabis flower and concentrates they would purchase in the next 30 days at escalating prices. We estimated (a) demand indices and own-price elasticities using nonlinear exponential demand models and (b) group- and individual-level cross-price elasticities using log-linear demand models. The estimated rate of change in demand elasticity (α) was 0.00066 for cannabis flower (SE = 0.00002, p < .001) and 0.00058 for cannabis concentrate (SE = 0.00002, p < .001). Group-level cross-price elasticity estimate (slope = -0.075, SE = 0.0135, p < .001) indicated that cannabis flower and concentrates were weak complements. Individual-level cross-price elasticity estimates showed that flower and concentrates were treated as independent by 76.2% of the users, as complements by 19.0% of the users, and as substitutes by 4.8% of the users. The findings suggested that cannabis flower and concentrates were overall weak complements and for most adult cannabis users were treated as independent of each other. Price and tax policies regulating either cannabis form may have minimal impacts on the other form. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Concurrent validity of the marijuana purchase task: a meta-analysis of trait-level cannabis demand and cannabis involvement

BACKGROUND AND AIMS

The Marijuana Purchase Task (MPT) is increasingly used to measure cannabis reinforcing value and has potential use for cannabis etiological and regulatory research. This meta-analysis sought to evaluate for the first time the MPT's concurrent validity in relation to cannabis involvement.

METHODS

Electronic databases and pre-print repositories were searched for MPT studies that examined the cross-sectional relationship between frequency and quantity of cannabis use, problems, dependence, and five MPT indicators: intensity (i.e. unrestricted consumption), Omax (i.e. maximum consumption), Pmax (i.e. price at which demand becomes elastic), breakpoint (i.e. first price at which consumption ceases), and elasticity (i.e. sensitivity to rising costs). Random effects meta-analyses of cross-sectional effect sizes were conducted, with Q tests for examining differences by cannabis variables, meta-regression to test quantitative moderators, and publication bias assessment. Moderators included sex, number of MPT prices, variable transformations, and year of publication. Populations included community and clinical samples.

RESULTS

The searches yielded 14 studies (n = 4077, median % females: 44.8%: weighted average age = 29.08 [SD = 6.82]), published between 2015 and 2022. Intensity, Omax , and elasticity showed the most robust concurrent validity (|r's| = 0.147-325, ps < 0.014) with the largest significant effect sizes for quantity (|r| intensity = 0.325) and cannabis dependence (|r| Omax  = 0.320, |r| intensity = 0.305, |r| elasticity = 0.303). Higher proportion of males was associated with increased estimates for elasticity-quantity and Pmax -problems. Higher number of MPT prices significantly altered magnitude of effects sizes for Pmax and problems, suggesting biased estimations if excessively low prices are considered. Methodological quality was generally good, and minimal evidence of publication bias was observed.

CONCLUSIONS

The marijuana purchase task presents adequate concurrent validity to measure cannabis demand, most robustly for intensity, Omax , and elasticity. Moderating effects by sex suggest potentially meaningful sex differences in the reinforcing value of cannabis.

A hypothetical lottery task to assess relative resource allocation toward alcohol and cannabis

OBJECTIVE

Relative spending on substances (vs. alternatives) is predictive of several substance use outcomes, but it can be challenging to assess. We examined a novel method of assessing relative resource allocation through the use of a hypothetical lottery task wherein participants assume they collected $100,000 United States dollars in lottery winnings and were tasked with allocating their winnings across spending categories (e.g., savings, leisure, alcohol, cannabis). We hypothesized relative allocation of funds toward alcohol and cannabis would be positively associated with more use and problems of each substance.

METHOD

College students (N = 479; Mage = 19.9 [SD = 2.2]) reported on their substance use and problems, alcohol and cannabis demand, and the hypothetical lottery task.

RESULTS

Relative resource allocation toward alcohol and cannabis on the lottery task positively correlated with alcohol and cannabis demand indices (intensity, breakpoint, Omax, and elasticity [negatively]), respectively. Using zero-inflated modeling, greater relative allocation toward alcohol positively related to alcohol use and problems in models that controlled for alcohol demand indices. For cannabis, relative resource allocation was also positively associated with cannabis use, but not problems, independently from cannabis demand indices.

CONCLUSIONS

Results provide initial support for the hypothetical lottery task as an indicator of relative resource allocation toward substances. Generally, these results extend previous behavioral economic research demonstrating the utility of relative resource allocation as a unique predictor of clinically relevant outcomes. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Substance-related cross-commodity purchase tasks: A systematic review

OBJECTIVE

In the context of behavioral economics, drug use is a choice to which an individual may allocate responding despite the presence of alternative response possibilities. To examine the demand for a drug in an environment in which other drugs or nondrug alternatives are present, researchers often use a cross-commodity purchase task. These tasks allow participants to make choices across several reinforcers at varied unit prices and may elucidate behavioral economic patterns of substitutability and complementarity. The objective of this study was to conduct a systematic review of cross-commodity purchase task studies with human participants.

METHOD

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we screened 46 full-text studies (from 456 total records obtained from PsycINFO and PubMed databases and reference list search), yielding a final sample of 35 studies.

RESULTS

The drug category with the largest number of studies assessed was tobacco and nicotine products. The most consistent economic relationships found were substitutability of traditional cigarettes by e-cigarettes and e-liquid, and both legal and illegal cannabis for the other; however, other substitutable and complementary relationships were observed (e.g., substitution of food for cigarettes, a complementary relationship between alcohol and cannabis).

CONCLUSIONS

We discuss the implications of the results of this review from a treatment and harm reduction standpoint, highlight areas for future research particularly among drug categories with few studies and evaluating ecological validity of hypothetical measures, and make best practice recommendations for future cross-commodity drug-related purchase task research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Do alcohol and cannabis substitute or complement each other? Analysis from behavioral economics for formulating public policy on substance use in Colombia

After alcohol and tobacco, cannabis is the third most used substance among young Colombian adults, and many consume alcohol and cannabis concomitantly. However, academics have debated whether these substances substitute or complement each other among consumers. Understanding the relationship between the price and demand for psychoactive substances can clarify consumption patterns and help to develop strategies to reduce harmful consumption. This paper summarizes worldwide evidence of both complementary and substitution relationships and discusses the most probable relationship types in Colombia based on its substance use patterns and current regulations. Like other countries, Colombia is considering legalizing recreational cannabis use. However, there is a growing concern that legalization would increase the negative impacts of cannabis and increase alcohol use among the young adult population. The lack of Colombian empirical studies about the impacts of legal changes on the cannabis market makes it difficult to predict how such changes would affect demand and price elasticities.

Cannabis Use Disorder: A Behavioral Economic Perspective

Purpose of Review

To explore relations between behavioral economic demand for cannabis and cannabis use disorder (CUD). Prior reviews have focused on drug demand in relation to use outcomes more generally. Complementing and enhancing prior work synthesizing research on cannabis demand, the present review endeavors to determine whether specific demand indices derived from the marijuana purchase task are most reliably related to CUD. Additionally, sociodemographic characteristics of participants in these studies were reviewed to identify whether certain populations were underrepresented in behavioral economic cannabis research.

Recent Findings

Behavioral economic demand is related to CUD; intensity and elasticity of cannabis demand were consistently associated with CUD diagnosis and severity. However, frequently, only select demand indices were assessed or reported, precluding the ability to confirm which indices are superior for denoting CUD risk. Further, most studies enrolled samples that were predominately young adults, Caucasian, and male.

Summary

As CUD becomes more prevalent in the wake of cannabis legalization, identification of robust predictors of CUD risk is paramount. Cannabis demand is consistently associated with CUD; however, individual indices of import in this relationship remain ambiguous. Subsequent research is needed to confirm index-specific markers of disordered cannabis use, and whether links between demand and CUD generalize across diverse populations.

The effect of next day responsibilities and an adaptive purchase task on cannabis demand

BACKGROUND

The marijuana purchase task (MPT) is a commonly used behavioral economic measure of relative cannabis value (i.e. demand) that presents specific methodological concerns due to non-standardized measurement, variability in modality of use, and evolving legalization policies. Refinement of the task is critical to improve task ecological validity and accurate measurement of cannabis demand. The present study examined the construct validity of an adaptive MPT that allowed for participant selection of their preferred cannabis-based product and unit of measurement and the effect of next-day responsibilities on demand.

METHODS

Participants reporting at least monthly cannabis use (N = 186, 40.3 % women, Mage = 33.59) were recruited via Amazon Mechanical Turk and completed the original MPT and our adaptive form with 2 next-day responsibilities scenarios (no responsibilities vs. morning job interview) for each MPT. Cannabis use motives, problems, and risk for cannabis use disorder were also assessed.

RESULTS

Cannabis demand was sensitive to next-day responsibility, with higher hypothetical consumption observed in the no responsibilities condition. Responsibility-related decreases in Omax (F(1,185) = 4.83, p = .029, η2p = .03) were significantly greater on the adaptive MPT than the original MPT. Demand indices derived from the adaptive MPT were significantly correlated with cannabis problems (rbreakpoint = .19, rPmax = 0.18, relasticity=-0.18) and motives (rrange=-.32-.25), and demand metrics from the original MPT.

CONCLUSIONS

Results provide preliminary support for the construct validity of an adaptive MPT and suggest that early-morning work responsibilities may reduce cannabis demand. Continued research is needed to further refine this task and determine implications for cannabis use disorder intervention and prevention approaches.

Behavioral Economic Assessment of Alcohol and Cigarette Demand in Smokers With Alcohol Use Disorder

Background and Objectives: Behavioral economic purchase tasks are widely used to assess drug demand in substance use disorder research. Comorbid alcohol use is common among cigarette smokers and associated with greater difficulty in quitting smoking. However, demand for alcohol and cigarettes in this population has not been fully characterized. The present study addressed this gap by examining alcohol and cigarette demand among treatment-seeking smokers with alcohol use disorder (AUD). Methods: Alcohol and cigarette demand was assessed among 99 smokers with AUD. We conducted Principal Component Analysis (PCA) and correlational analyses on the demand indices. Results: Participants showed higher demand for alcohol than for cigarettes, as evidenced lower elasticity (resistance to increasing price) and higher O_max (maximum response output for drug). PCA revealed a two-factor structure (Persistence and Amplitude) for both alcohol and cigarette demand indices. Cigarette-related demand indices were positively correlated with nicotine dependence, but alcohol-related demand indices were not associated with alcohol dependence, suggesting dissociation between alcohol demand and use behaviors. Discussion and Conclusions: Our results suggest that smokers with AUD were more resistant to price elevations in relation to reducing alcohol consumption as compared to cigarette consumption, suggesting preferential demand for alcohol over cigarettes. However, it is unclear how acute substance exposure/withdrawal impacts the demand indices. Scientific Significance: Potentially differential alcohol and cigarette demands among smokers with AUD should be considered in the concurrent treatment of smoking and alcohol.