Initial Development of an E-cigarette Purchase Task: A Mixed Methods Study

Cannabis demand and use among veterans: A prospective examination

OBJECTIVE

Cannabis demand (i.e., relative value), assessed cross-sectionally via a hypothetical marijuana purchase task (MPT), has been associated with use, problems, and dependence symptoms, among others. However, limited work exists on the prospective stability of the MPT. Furthermore, cannabis demand among veterans endorsing cannabis use, and the prospective cyclical relationship between demand and use over time, have yet to be investigated.

METHOD

Two waves of data from a veteran sample (N = 133) reporting current (past 6-month) cannabis use were analyzed to assess stability in cannabis demand over 6 months. Autoregressive cross-lagged panel models (CLPMs) assessed the longitudinal associations between demand indices (i.e., intensity, Omax, Pmax, breakpoint) and cannabis use.

RESULTS

Baseline cannabis use predicted greater intensity (β = .32, p < .001), Omax (β = .37, p < .001), breakpoint (β = .28, p < .001), and Pmax (β = .21, p = .017) at 6 months. Conversely, baseline intensity (β = .14, p = .028), breakpoint (β = .12, p = .038), and Pmax (β = .12, p = .043), but not Omax, predicted greater use at 6 months. Only intensity demonstrated acceptable prospective reliability.

CONCLUSIONS

Cannabis demand demonstrated stability over 6 months in CLPM models, varying along with natural changes in cannabis use. Importantly, intensity, Pmax, and breakpoint displayed bidirectional predictive associations with cannabis use, and the prospective pathway from use to demand was consistently stronger. Test-retest reliability ranged from good to poor across indices. Findings highlight the value of assessing cannabis demand longitudinally, particularly among clinical samples, to determine how demand fluctuates in response to experimental manipulation, intervention, and treatment. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The electronic nicotine delivery system (ENDS) purchase task: Are results sensitive to price framing?

Extension of the cigarette purchase task (CPT) to electronic nicotine delivery systems (ENDS) is complicated by the heterogeneous nature of this product class, as ambiguity exists regarding the appropriate price-frame (i.e., unit of the product being purchased). We explored correlations between ENDS purchase task (E-CPTs) outcomes featuring two common price-frames: 10 puffs and 1 mL of liquid. Adult exclusive ENDS users (N = 19) and dual users of ENDS and cigarettes (N = 16) completed two own-brand E-CPTs. One E-CPT used "10 puffs" as its price-frame; the other used "1 mL of liquid." Five outcomes were generated for each E-CPT: breakpoint, intensity, Omax, Pmax, and α. Exploratory Factor Analyses (EFA) considered how these outcomes captured latent structures of demand for ENDS. Spearman correlations in E-CPT outcomes assessed within-person variation between price-frames. Analyses also considered whether correlations differed by user group. E-CPT outcomes were highly correlated across price-frames (ρs > 0.57, ps < .001), and EFA revealed little difference in how outcomes from the tasks loaded onto two latent structures of demand ("Persistence" and "Amplitude") reported in the previous literature. The magnitude of correlations for E-CPT outcomes tended to be higher for exclusive ENDS users than for dual users. Participant responses to purchase task outcomes were similar across two E-CPT price-frames. Using "10 puffs" as a price-frame may be a generalizable approach among heterogenous groups of ENDS users, but researchers should consider their target population and structure the E-CPT to reflect participants' knowledge and purchasing behaviors. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

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.

Device features and user behaviors as predictors of dependence among never-smoking electronic cigarette users: PATH Wave 4

INTRODUCTION

Electronic cigarettes (ECIGs) vary greatly in their ability to deliver nicotine, which suggests they may also vary in their ability to produce dependence. This study examined individual and combined ECIG device features, and also user behaviors, as predictors of dependence in never-smoking ECIG users. Methods Data were collected from 711 current ECIG users who had smoked <100 cigarettes in their lifetime at Wave 4 of the Population Assessment of Tobacco and Health (PATH) Study. Multivariable linear regressions examined individual (e.g., contains nicotine, uses a tank, flavor preference) and combined (e.g., refillable tanks, refillable mods) device features, and user behaviors (e.g., uses/day) as predictors of dependence, withdrawal, and craving after accounting for demographic variables. Results Results for ECIG dependence and craving showed a similar pattern; higher levels were observed for older age, more frequent past 30-day use, using an ECIG containing nicotine (vs no nicotine), and using a non-refillable cartridge or refillable tank style (vs disposables). Higher withdrawal levels were observed for higher education levels and individual device features of tank (vs no tank), cartridge (vs no cartridge), refillable (vs non-refillable), and "other" flavor preference (vs tobacco flavor). Lower withdrawal levels were associated with a preference for sweet/fruit flavor(s) (vs tobacco flavor). Conclusions Few use behaviors and device features, whether examined alone or in combination, predicted dependence-related outcomes. Findings underscore the challenge with regulating ECIG products in the current marketplace, which is inundated with a myriad of device types.

Vapers exhibit similar subjective nicotine dependence but lower nicotine reinforcing value compared to smokers

INTRODUCTION

E-cigarette use has increased rapidly over the last 10 years, mostly among smokers and ex-smokers. Although there may be some degree of dependency on nicotine via e-cigarette use, the nature of this dependency is poorly understood. The aim of this paper is to use tasks from behavioural economics to compare the value that smokers place on tobacco cigarettes to the value that vapers place on e-cigarettes.

METHOD

Exclusive current smokers (n = 25) and vapers (n = 20) attended one session where they completed the Cigarette/e-cigarette Dependence Scale, the Cigarette/e-cigarette Purchasing Task (CPT) and the Concurrent Choice Task (CCT). The CPT requires participants to indicate how many puffs of their chosen product they would purchase at increasing price points. The CCT requires participants to choose between earning a money point or a point towards a cigarette/e-cigarette after being presented with a neutral, money or cigarette/e-cigarette cue.

RESULTS

Overall scores on the self-report scales suggest a comparable level of dependency between smokers and vapers. The CPT revealed that vapers are more sensitive than smokers to escalating costs as consumption declined as costs increased. On the CCT, when primed with money, vapers showed a decrease in choosing e-cigarettes.

CONCLUSION

These findings suggest that, on behavioural economic tasks, tobacco cigarettes have a higher relative value than e-cigarettes. Vapers appear to place a lower limit on what they will spend to access e-cigarettes and more readily choose money over e-cigarette puffs when primed by money cues.

E-Cigarette Demand: Impact of Commodity Definitions and Test-Retest Reliability

INTRODUCTION

Behavioral economic demand provides a multidimensional understanding of reinforcement. Commodity purchase tasks are an efficient method for measuring demand in human participants. One challenge in translating these procedures to electronic nicotine delivery systems (ENDS or e-cigarettes) is defining commodity units given the lack of standardization in the e-cigarette marketplace.

AIMS AND METHODS

The purpose of this study was to directly compare methods of operationalizinge-cigarette purchases, puffs, cartridges, and mLs liquid, using a within-subject design. Participants (N = 132) reporting past week e-cigarette use were recruited using crowdsourcing. Purchase tasks were completed operationalizing e-cigarette units as puffs or cartridges at baseline and puffs or mLs liquid at a 3-month follow-up.

RESULTS

Bivariate associations supported convergent and discriminant validity with the largest effect size correlations for intensity and elasticity observed for the puff version. Interaction models suggested that product preferences moderated the relationship between time-to-first use and cartridge demand with larger effect size correlations among persons reporting a preference for JUULs, but weaker relationships among persons reporting other device preferences. Puff intensity (rxx = .61) and elasticity (rxx = .62) showed good test-retest reliability for participants reporting stable consumption, but poor test-retest reliability for individuals with changed consumption levels (intensity rxx = -.08; elasticity rxx = -.10).

CONCLUSIONS

This study highlights the relevance of commodity definitions in the e-cigarette purchase task. Puffs as an experimental commodity may provide flexibility for studying e-cigarette demand in heterogenous or unknown populations, whereas more tailored or personalized approaches like cartridge or mL-based tasks will likely be helpful when studying known subgroups.

IMPLICATIONS

The commodity purchase task procedure is widely used for understanding cigarette and e-cigarette demand in nicotine dependence research. This study evaluates the importance of operational definitions of e-cigarette commodities in the purchase task (ie, puffs, cartridges, or mLs liquid). Puffs may provide a more flexible commodity unit when evaluating e-cigarette demand in general or heterogenous populations, whereas device-specific units may prove more valuable when studying populations with consistent and known product use.

Behavioral economic measurement of cigarette demand: A descriptive review of published approaches to the cigarette purchase task

The cigarette purchase task (CPT) is a behavioral economic method for assessing demand for cigarettes. Growing interest in behavioral correlates of tobacco use in clinical and general populations as well as empirical efforts to inform policy has seen an increase in published articles employing the CPT. Accordingly, an examination of the published methods and procedures for obtaining these behavioral economic metrics is timely. The purpose of this investigation was to provide a review of published approaches to using the CPT. We searched specific Boolean operators (["behavioral economic" AND "purchase task"] OR ["demand" AND "cigarette"]) and identified 49 empirical articles published through the year 2018 that reported administering a CPT. Articles were coded for participant characteristics (e.g., sample size, population type, age), CPT task structure (e.g., price framing, number and sequence of prices; vignettes, contextual factors), and data analytic approach (e.g., method of generating indices of cigarette demand). Results of this review indicate no standard approach to administering the CPT and underscore the need for replicability of these behavioral economic measures for the purpose of guiding clinical and policy decisions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Withdrawal Symptoms From E-Cigarette Abstinence Among Former Smokers: A Pre-Post Clinical Trial

INTRODUCTION

The major aim of this study was to test whether abstinence from e-cigarettes causes withdrawal symptoms in former smokers.

METHODS

We conducted an unblinded, within-participants, pre-post clinical trial in which 109 former smokers who were current daily electronic cigarette (e-cigarette) users used their own e-cigarette for 7 days followed by 6 days of biologically confirmed abstinence engendered via an escalating contingency payment system. Participants monitored symptoms of nicotine withdrawal daily via an Interactive Voice Response system. They also attended three laboratory visits per week for carbon monoxide and cotinine testing to verify abstinence.

RESULTS

Half of participants completely abstained for a week. All the Diagnostic and Statistical Manual, Fifth Edition (DSM-5) tobacco withdrawal symptoms, craving for e-cigarettes, craving for tobacco cigarettes, and the four possible new withdrawal symptoms (anhedonia, impulsivity, mood swings, and positive affect) increased during abstinence. Weight increased and heart rate decreased with abstinence. Symptoms showed the prototypical inverted U time pattern of a withdrawal state. The magnitude of withdrawal appeared to be somewhat less than that in a prior study of abstinent daily tobacco cigarette smokers. More severe withdrawal on the first 2 days of abstinence did not predict abstinence on the last day of the study.

CONCLUSIONS

Former smokers who are daily e-cigarette users transfer physical dependence on tobacco cigarettes to dependence on e-cigarettes. The severity of withdrawal from e-cigarettes appears to be only somewhat less than that from daily tobacco cigarette use. Replication tests that include placebo controls, testing for pharmacological specificity, and including never-smokers, non-daily e-cigarette users and dual users are indicated.

IMPLICATIONS

Our results indicate e-cigarettes can maintain physical dependence. This adverse effect should be included in any risk vs. benefit calculation. Also, potential and current e-cigarette users should be informed that abrupt cessation of e-cigarettes can cause withdrawal symptoms.

TRIAL REGISTRATION

NCT02825459.

Validation of an E-cigarette Purchase Task in Advanced Generation Device Users

INTRODUCTION

Behavioral economic purchase tasks are used to estimate the reinforcing value of drugs by asking participants how much they would purchase across a range of increasing prices. We sought to validate such a task for e-cigarettes in experienced users of advanced generation, tank-style devices.

METHODS

Dual users of cigarettes and e-cigarettes (N = 54) and exclusive e-cigarette users (N = 59) attended one session during which they completed assessments including two versions of the E-cigarette Purchase Task: one that asked how many puffs of their e-cigarette they would purchase in 24 hours at varying prices and one that asked how many mLs of e-liquid they would purchase. We correlated purchase task outcomes with other measures of e-cigarette use. We also compared the tasks across dual and exclusive users.

RESULTS

Indices derived from the mLs-based task were more likely to be correlated with self-reported use rates, e-cigarette dependence, and cotinine levels than the puffs-based task. Exclusive users showed greater demand on than dual users only on the mLs version when using an F-test comparison method, while multivariate analysis of variance (MANOVA) results showed that dual users showed greater demand only on the puffs task.

CONCLUSIONS

Results indicate that the mLs version had greater validity than the puffs version in terms of clinical indices. Dual users may still be on a trajectory to fully switching to e-cigarettes; thus, puffs as a measure may be more intuitive, as this measure is shared by cigarettes and e-cigarettes. For exclusive users, the unit they purchase their e-liquid in may be the most relevant unit and better capture their demand for that product.

IMPLICATIONS

Behavioral economic purchase tasks have been widely used to understand nicotine use. We have developed two versions of a purchase task for e-cigarette use and compared the two versions in users of advanced generation e-cigarette devices. We found that the mLs version of the task better-reflected use patterns relative to a puffs version, which suggests that participants struggle to place monetary value on a unit of consumption (ie, puffs). Validated measures of e-cigarette reinforcement will be important as researchers and regulators determine which features of these products contribute to reinforcing efficacy.

Behavioral economic demand as a unifying language for addiction science: Promoting collaboration and integration of animal and human models

The intersection of pharmacological, psychological, and economic theory within behavioral economics has helped advance an understanding of substance use disorder. A notable contribution of this approach is the conceptualization of reinforcement from a behavioral economic demand perspective. Demand analyses provide a multidimensional view of reinforcement in which distinct behavioral mechanisms are measured that impact decision making and drug consumption. This review describes the state of research on behavioral economic demand as a common language for addiction science researchers across varied model systems and stages of a translational continuum. We first provide an overview of the theoretical concepts and procedures used to evaluate demand in animal and human models. The potential for demand to serve as a common language for diverse research groups in psychopharmacology and addiction science (e.g., those evaluating neurobehavioral outcomes, medications development, clinical practice) is then described. An overview is also provided of existing empirical studies that, while small in number, suggest good linguistic and conceptual overlap between animal and human demand models when studying biological, environmental, and pharmacological individual difference vulnerabilities underlying drug-taking behavior. Refinement of methodological procedures and incorporation of more nuanced environmental features should help improve correspondence between animal and human demand studies as well as clinical translation of such findings. Our hope is that this review and commentary ultimately serves as inspiration for new collaborative efforts involving behavioral economic demand between animal and human researchers who share a common goal of improving substance use treatment outcomes and broader psychological wellbeing. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Withdrawal Symptoms From E-Cigarette Abstinence Among Adult Never-Smokers: A Pilot Experimental Study

INTRODUCTION

Use of e-cigarettes among never-smokers has substantially increased; yet there are few descriptions of the consequences of such use. We assessed whether adult never-smokers can have withdrawal from cessation of e-cigarettes.

METHODS

In an un-blinded pre-post clinical trial, 30 never-smoker daily e-cigarette users used their own nicotine-containing e-cigarette for 7 days followed by 6 days of biologically confirmed abstinence. Participants monitored symptoms of nicotine withdrawal nightly via an Interactive Voice Response system. They attended three lab visits/week to provide expired carbon monoxide and urine samples to determine compliance.

FINDINGS

Abstinence increased all the DSM5 symptoms of tobacco withdrawal and this occurred in the majority of participants. The increase in severity of withdrawal was small and rarely impaired functioning.

CONCLUSIONS

Our finding suggests that withdrawal symptoms can occur in never-smokers who stop e-cigarettes abruptly. However, the severity of withdrawal appears to be small and may not be of clinical or regulatory significance. Although our sample size was small and thus replication tests of our results are indicated, it may be prudent to warn never-smokers that withdrawal symptoms may occur.

IMPLICATIONS

This study indicates that withdrawal symptoms can occur in never-smokers who are daily e-cigarette users. However, the severity of withdrawal from e-cigarette abstinence in never-smokers appears to be small and may not be of clinical or regulatory significance. Given our small sample size, replication of our results is warranted. Nevertheless, it might be prudent to warn never-smokers of addiction to e-cigarettes.Clinical Trial Registration = NCT02825459.

Electronic cigarette dependence and demand among pod mod users as a function of smoking status

Electronic cigarette (e-cigarette) use continues to proliferate with fast-paced product evolution. Pod mod e-cigarettes emerged in the market in 2015 and have changed the tobacco landscape again. However, little is known regarding their addiction potential among users. The current study describes e-cigarette dependence and demand among pod mod users as a function of smoking status (current smokers/dual users, former smokers, and never smokers). Participants were 593 young adult (M_age = 25.9 years) JUUL users recruited via Amazon's Mechanical Turk. Respondents were specifically recruited based on current use of pod mods (but may also be using other e-cigarette devices) and smoking status (never, former, and current/dual users). Participants completed online measures assessing e-cigarette dependence and demand. Dual users of pod mods and cigarettes displayed greater e-cigarette dependence compared to current pod mod users with no history of cigarette smoking (p = .033). Similarly, dual users showed the greatest levels of e-cigarette demand compared to both former smokers and those without a history of smoking (ps < .05). Dual users displayed the greatest e-cigarette dependence and demand. Future research should directly assess potential mechanisms for this effect and continue to monitor e-cigarette dependence as the tobacco landscape changes with the emergence of new e-cigarette products and innovations. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Abuse liability of electronic cigarettes in men who are experienced electronic cigarette users

Most electronic cigarettes (e-cigs) aerosolize a nicotine-containing liquid that users inhale. Few experimental studies have examined e-cig abuse liability (the extent to which use of these products may lead to persistent and/or problematic use). In this study, 24 experienced male e-cig users completed 4 sessions that differed byproduct used: own e-cig (OWN), an eGo e-cig filled with participants' own brand/flavor liquid in 0 mg/mL nicotine (e-cig0), an eGo e-cig filled with the highest nicotine concentration available in participants' own brand/flavor (e-cighighest), and a U.S. Food and Drug Administration-approved nicotine inhaler (IN). Outcome measures included crossover point on the multiple-choice procedure, plasma nicotine delivery, and subjective effect profile. After 10 puffs, a significantly higher mean crossover point was observed for OWN at $1.35 (SD = 0.90) compared to e-cighighest at $0.88 (SD = 0.89), e-cig0 at $0.83 (SD = 0.79), and IN at $0.72 (SD = 0.84). Significant increases in mean plasma nicotine concentration were observed for OWN at 7.94 ng/mL (SD = 6.19) and e-cighighest at 7.51 ng/mL (SD = 5.39). Significant reductions in abstinence symptom suppression and higher ratings of satisfaction were observed for OWN and e-cighighest, with significantly less suppression and lower ratings of satisfaction for e-cig0 and IN. These findings suggest that human laboratory methods can be used to assess e-cig abuse liability and that nicotine-containing e-cigs have greater abuse liability than nicotine-free e-cigs and the IN. Potential regulations intended to limit e-cig abuse liability should be tested using these or similar procedures. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Examination of a mouthpiece-based topography device for assessing relative reinforcing effects of e-cigarettes: A preliminary study

The assessment of vaping topography has helped to identify characteristics associated with distinct vaping patterns. Available puff topography devices do not alter the subjective effects of vaping. However, one central construct related to drug abuse, unexplored in prior studies, is whether relative reinforcing effects (RRE) of vaping change when using a topography device. We examined the RRE of vaping when individuals vape through an e-cigarette with a mouthpiece topography device attached versus their own e-cigarette. Associations of demand indices for participants' own e-cigarette and for a research e-cigarette with a topography device were also explored. Forty-three e-cigarette users attended 1 experimental session where they completed 2 purchase tasks in different units of consumption, ml and puffs, with their preferred e-cigarette and with an e-cigarette with a mouthpiece. Puff topography was measured in the mouthpiece condition. All four purchase tasks showed the predicted inverse relationship between purchase and price. No differences in most demand indices were observed between both e-cigarettes, except for breakpoint (lowest price that suppresses consumption) and Omax (maximum expenditure) in ml units which both decreased when participants vaped through the mouthpiece device. Demand indices in ml units were more strongly associated. Data from the purchase tasks suggests that the presence of a mouthpiece topography device does not influence the RRE of vaping among e-cigarette users. Demand for e-cigarettes seems more consistent in ml units. Our results further evidence that mouthpiece topography devices represent a valid and reliable instrument to study RRE of e-cigarettes and, by extension, abuse liability. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Behavioral economic demand assessments in the addictions

Behavioral economics in the addictions is the application of both economics and psychology to study multifaceted components of substance use decision-making behavior. One such component is demand: the relative value of a substance for a user (i.e., the association between drug use and cost). The degree to which a user values a substance can be measured via performance on hypothetical purchase tasks which replicate drug purchase and consumption. Demand has been evaluated across substances, including alcohol, marijuana, tobacco, and alternative tobacco products. Recent advances in the study of demand have greatly improved the assessment of drug value, including application to novel products, selection of optimal task unit, assessment of demand in naïve or potential future users, and the importance of instructional set specificity.

Brief Assessment of Cigarette Demand (BACD): Initial development and correlational results in adults and adolescents

Developing briefer behavioral economic measures is an important priority to ensure that these measures can be used in a variety of different contexts and to reduce participant burden. We developed and sought to validate a Brief Assessment of Cigarette Demand (BACD). A 17-item Cigarette Purchase Task (CPT) and a 3-item BACD were completed concurrently in 2 community samples of smokers (Study 1, adult smokers [n = 80] with substance use disorders; Study 2, adolescent smokers [n = 81]). Responses on the CPT and BACD were compared on the following demand indices: (a) intensity (the number of cigarettes requested at no cost), (b) Omax (the maximum expenditure on cigarettes in a 24-hr period), and (c) breakpoint (the point at which consumption is totally suppressed/no cigarettes are purchased). Correlations of demand indices with cigarettes per day and nicotine dependence were calculated. Measures of cigarette demand on the CPT and BACD were significantly correlated, albeit at very different magnitudes, for all 3 indices in the adult sample (intensity, r = .86; breakpoint, r = .23; and Omax, r = .43) and for 2 of the indices in the adolescent sample (intensity, r = .97; breakpoint, r = .33). The CPT and BACD relationships with smoking and nicotine dependence were similar for breakpoint and intensity but not for Omax. As initial findings were mixed, additional validation work is recommended to improve psychometric properties before adoption. Valid brief measures of demand could have utility for research and treatment of addictive disorders. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Evaluating non-medical prescription opioid demand using commodity purchase tasks: test-retest reliability and incremental validity

RATIONALE

Non-medical prescription opioid use and opioid use disorder (OUD) present a significant public health concern. Identifying behavioral mechanisms underlying OUD will assist in developing improved prevention and intervention approaches. Behavioral economic demand has been extensively evaluated as a measure of reinforcer valuation for alcohol and cigarettes, whereas prescription opioids have received comparatively little attention.

OBJECTIVES

Utilize a purchase task procedure to measure the incremental validity and test-retest reliability of opioid demand.

METHODS

Individuals reporting past year non-medical prescription opioid use were recruited using the crowdsourcing platform Amazon Mechanical Turk (mTurk). Participants completed an opioid purchase task as well as measures of cannabis demand, delay discounting, and self-reported pain. A 1-month follow-up was used to evaluate test-retest reliability.

RESULTS

More intense and inelastic opioid demand was associated with OUD and more intense cannabis demand was associated with cannabis use disorder. Multivariable models indicated that higher opioid intensity and steeper opioid delay discounting rates each significantly and uniquely predicted OUD. Increased opioid demand intensity, but not elasticity, was associated with higher self-reported pain, and no relationship was observed with perceived pain relief from opioids. Opioid demand showed acceptable-to-good test-retest reliability (e.g., intensity rxx = .75; elasticity rxx = .63). Temporal reliability was lower for cannabis demand (e.g., intensity rxx = .53; elasticity rxx = .58) and discounting rates (rxx = .42-.61).

CONCLUSIONS

Opioid demand was incrementally valid and test-retest reliable as measured by purchase tasks. These findings support behavioral economic demand as a clinically useful measure of drug valuation that is sensitive to individual difference variables.

Behavioral Economic Purchase Tasks to Estimate Demand for Novel Nicotine/tobacco Products and Prospectively Predict Future Use: Evidence From The Netherlands

INTRODUCTION

The demand for alternative nicotine/tobacco products is not well established. This paper uses a behavioral economic approach to test whether smokers have differential demand for conventional factory-made, electronic, and very low nicotine content cigarettes (FMCs/ECs/VLNCs) and uses the prospective cohort design to test the predictive validity of demand indices on subsequent use of commercially available FMCs and ECs.

METHODS

Daily smokers (≥16 years) from the Netherlands completed an online survey in April 2014 (N = 1215). Purchase tasks were completed for FMCs, ECs, and VLNCs. Participants indicated the number of cigarettes they would consume in 24 h, across a range of prices (0-30 euro). The relationship between consumption and price was quantified into four indices of demand (intensity, Pmax, breakpoint, and essential value). A follow-up survey in July 2015 measured FMC and EC use.

RESULTS

At baseline, greater demand was observed for FMCs relative to ECs and VLNCs across all demand indices, with no difference between ECs and VLNCs. At follow-up, greater baseline FMC demand (intensity, essential value) was associated with lower quit rates and higher relapse. EC demand (Pmax, breakpoint, essential value) was positively associated with any EC use between survey waves, past 30 day EC use, and EC purchase between waves.

CONCLUSIONS

Smokers valued FMCs more than ECs or VLNCs, and FMCs were less sensitive to price increases. Demand indices predicted use of commercially available products over a 15 month period. To serve as viable substitutes for FMCs, ECs and VLNCs will need to be priced lower than FMCs.

IMPLICATIONS

Purchase tasks can be adapted for novel nicotine/tobacco products as a means to efficiently quantify demand and predict use. Among current daily smokers, the demand for ECs and VLNCs is lower than FMCs.

Behavioral Economic Research in Addiction as an Area of Growth for the Experimental Analysis of Behavior

Behavioral economics, a synthesis of the experimental analysis of behavior (EAB) and economics, seeks to determine the relative value of reinforcers as a function of various environmental constraints. Early animal and human studies often focused on drug reinforcement, and this has continued to the present. In particular, behavioral economic analyses of human and animal behavior in relation to nicotine and cigarette smoking have contributed to a greater understanding of this behavior, and to a greater reliance on these methods in the field of smoking cessation treatment, tobacco regulatory science and tobacco control. In this commentary, we briefly describe the history of behavioral economics in the context of EAB methods, the particular contribution of these methods to understanding cigarette smoking and the advance of tobacco regulation, as well as opportunities for growth and remaining challenges in this area. As behavioral economics continues to stimulate research and inform policy, we propose that the underlying elements of a rigorous analytic approach to understanding behavior are key contributors to the fruitfulness of this approach.

Studying the interactive effects of menthol and nicotine among youth: An examination using e-cigarettes

BACKGROUND

Tobacco products containing menthol are widely used by youth. We used e-cigarettes to conduct an experimental evaluation of the independent and interactive effects of menthol and nicotine among youth.

PROCEDURES

Pilot chemosensory experiments with fourteen e-cigarette users identified low (barely perceptible, 0.5%) and high (similar to commercial e-liquid, 3.5%) menthol concentrations. Sixty e-cigarette users were randomized to a nicotine concentration (0mg/ml, 6mg/ml, 12mg/ml) and participated in 3 laboratory sessions. During each session, they received their assigned nicotine concentration, along with one of three menthol concentrations in random counterbalanced order across sessions (0, 0.5%, 3.5%), and participated in three fixed-dose, and an ad-lib, puffing period. Urinary menthol glucuronide and salivary nicotine levels validated menthol and nicotine exposure. We examined changes in e-cigarette liking/wanting and taste, coolness, stimulant effects, nicotine withdrawal and ad-lib use.

RESULTS

Overall, the high concentration of menthol (3.5%) significantly increased e-cigarette liking/wanting relative to no menthol (p<0.001); there was marginal evidence of nicotine* menthol interactions (p=0.06), with an increase in liking/wanting when 3.5% menthol was combined with 12mg/ml nicotine, but not 6mg/ml nicotine. Importantly, both 0.5% and 3.5% menthol concentrations significantly improved taste and increased coolness. We did not observe nicotine or menthol-related changes in stimulant effects, nicotine withdrawal symptoms or ad-lib use.

CONCLUSIONS

Menthol, even at very low doses, alters the appeal of e-cigarettes among youth. Further, menthol enhances positive rewarding effects of high nicotine-containing e-cigarettes among youth.

Effect of Flavors and Modified Risk Messages on E-cigarette Abuse Liability

Objectives

To measure e-cigarettes' abuse liability compared to conventional tobacco cigarettes under flavor and message conditions amenable to regulation.

Methods

Two studies used 2×2 within-subjects designs with factors of e-cigarette flavor (Study 1: tobacco vs. menthol; Study 2: cherry vs. unflavored) and message (Study 1: reduced harm vs. no message; Study 2: reduced exposure to carcinogens vs. no message) with cigarette smokers (N(total) = 36). Linear mixed effects models assessed abuse liability for tobacco products. Outcomes included the price after which consumption is zero (the maximum amount participants would pay for a tobacco product) from the multiple choice procedure (MCP) and cigarette purchase task (CPT) and demand elasticity (price sensitivity) from the CPT.

Results

In the MCP, the price where consumption reached zero was significantly lower in all e-cigarette conditions except tobacco flavor (message or no message) compared to cigarettes (p < .05 each). Demand elasticity was significantly higher for menthol/no message and unflavored/reduced exposure message conditions relative to cigarettes (p < .05 each).

Conclusions

Flavors and modified risk messages included with e-cigarettes may affect e-cigarette abuse liability among smokers, suggesting regulatory pathways to influence demand for conventional and alternative tobacco products.