Comparison of Tobacco and Electronic Cigarette Reward Value Measured During a Cue-Reactivity Task: An Extension of the Choice Behavior Under Cued Conditions Procedure

Electronic cigarette cue reactivity in exclusive electronic cigarette users

BACKGROUND

Exposure to electronic cigarette (ECIG) cues increases craving for ECIGs among people who smoke cigarettes, including those without prior ECIG use experience. This study aimed to examine the effects of ECIG cue exposure in individuals who use ECIGs regularly but have minimal smoking history (<100 cigarettes lifetime).

METHODS

Participants (N = 42) attended two within-subjects conditions that differed by pictorial cue type: ECIG or neutral (water) cues. Each condition included two presentations of the condition-assigned cue type. Before and after each cue presentation, participants completed subjective measures of ECIG craving, anticipated relief from withdrawal, and mood. After the second cue presentation, participants completed ECIG delay discounting and behavioral economic tasks, with ECIG use quantified in puffs or in minutes of ECIG access. Linear mixed-effects regressions and paired-samples t-tests assessed the effects of cue type on these outcomes.

RESULTS

Ratings of ECIG craving and anticipation of relief from ECIG withdrawal increased significantly from pre- to post-cue exposure for ECIG cues relative to neutral cues (p's < .05). A similar pattern was observed for negative mood (p < .05). ECIG cues (versus neutral cues) also increased discounting of delayed minutes of ECIG access (p < .05) but not ECIG puffs.

CONCLUSIONS

This is the first study to demonstrate that ECIG cues increase ECIG craving and negative mood in individuals who vape but do not smoke cigarettes. Results have implications for restrictions on where vaping should be permitted.

Examining Electronic Nicotine Delivery System (ENDS) Cue Reactivity Using a Remote Platform: Cigarette and ENDS Desire in Dual Users

INTRODUCTION

Prior research shows that in-person exposure to electronic nicotine delivery systems (ENDS) use increases desire for cigarettes and ENDS. However, less is known about the impact of cues delivered during remote interactions. This study extends previous in-person cue work by leveraging a remote confederate-delivered cue-delivery paradigm to evaluate the impact of dual nicotine vaping (vs. sole smoking) on reactivity to an ENDS cue in individuals who smoke cigarettes.

METHODS

N=52 dual users (DU; current users of both combustible cigarettes and ENDS) and N=54 sole smokers (SS; users of combustible cigarettes only) observed a study confederate drinking bottled water (control cue) and then vaping an ENDS (active cue). Changes in desire for cigarettes and ENDS were compared between groups post-cue exposure.

RESULTS

Multilevel models, controlling for sex and cigarettes per day, revealed that the remote ENDS cue, but not water, significantly increased desire for both cigarettes and ENDS. Relative to SS, DU reported greater post-ENDS cue increases in ENDS desire but not cigarette desire.

CONCLUSIONS

A remote, confederate-delivered ENDS cue generalizes as a smoking and vaping cue, with DU showing greater reactivity than SS. This study provides the first evidence for the validity and feasibility of a remote, confederate-delivered ENDS cue reactivity paradigm.

IMPLICATIONS

This study provides support for the use of a remote platform, an increasingly popular method of conducting research since the onset of the COVID-19 pandemic, to employ confederate-delivered ENDS cues. Frequent observations of vaping via remote platforms and social media may contribute to the maintenance of single and dual product use.

The development and validation of an electronic nicotine delivery system (ENDS) image cue stimulus set

RATIONALE

Responsiveness to drug-related cues assesses drug reward in research studies. There are currently no validated visual image cues related to electronic nicotine delivery systems (ENDS), thus, this study aimed to develop and validate affective ENDS image cues.

METHODS

ENDS users and non-vaping individuals in the United States and Canada were recruited via Amazon MTurk. A total of 120 ENDS-related images and 56 neutral images, matched for visual similarity, were assessed. These images were either selected from public databases or were photographed by study staff. Closely adhering to the International Affective Picture System procedure, each participant rated 66 images one-by-one on dimensions of valence, arousal, dominance, and desire-to-vape where higher scores indicated greater feelings of happiness, excitement, loss of control, and desire to vape.

RESULTS

After excluding patterned responses, the data from 926 participants (610 ENDS users, and 316 non-vaping controls) were analyzed. When viewing ENDS-related images, desire-to-vape scores were correlated with valence (r = 0.55, p < 0.0005), arousal (r = 0.72, p < 0.0005), and dominance (r = 0.58, p < 0.0005) scores. Images that elicited greater desires to vape also elicited greater feelings of happiness and excitement, but less perceived control. Correlations between arousal and valence (r = 0.42, p < 0.0005) and dominance (r = 0.71, p < 0.0005) suggest that images that increased feelings of excitement also increased happiness and decreased perceived control.

CONCLUSIONS

Correlational findings of the affective ENDS-related images were similar to those of previous studies validating collections of tobacco and alcohol picture cues, supporting the future use of these stimuli in ENDS research.

Cue Reactivity to Electronic Cigarettes: A Systematic Review

Cue reactivity to Electronic Nicotine Delivery Systems (ENDS) has been studied by several researchers, yet the variability in user types (smokers, former smokers, dual users, exclusive ENDS users) and ENDS designs used between the studies may have undermined consistent results. This systematic review aims to give an overview of ENDS cue reactivity and how smoking status and device design may moderate this. A systematic search of Medline, Embase, Web of Science, PubMed and Cochrane was completed. All studies which reported findings on reactivity to ENDS cues in the form of craving or desire for ENDS or cigarettes, attention to cue, delay of gratification or economic decisions were included. Exclusion criteria were non-human subjects, non-adult participants or participants with comorbidities. Literature selection was carried out by 2 independent reviewers. The risk of bias and study quality were assessed using tools developed by Cochrane, BMJ and NHLBI. A total of 711 papers were screened and 22 studies were included in the current review. Study design, research question(s), population of interest, number of participants, dependent variable(s), ENDS generation and nicotine content used and study results were extracted. ENDS cues reliably induced ENDS craving, with no clear moderation by smoking status and no apparent moderation by device generation. In about half of the studies, ENDS cues induced craving for conventional cigarettes. Most studies used a smoker sample, thus limiting the conclusions that can be drawn on the moderation of cue reactivity by smoking status. The quality varied among studies but comparing the findings against the outcomes of only high-quality studies did not yield any different results. The results of this review support the notion of cue reactivity to ENDS, identifies gaps in current research on different user types and implies that ENDS design iterations have little impact on cue reactivity.

Study protocol: evaluation of the addictive potential of e-cigarettes (EVAPE): neurobiological, sociological, and epidemiological perspectives

BACKGROUND

Tobacco use is the largest preventable cause of diseases and deaths; reducing tobacco intake is, therefore, an urgent public health goal. In recent years, e-cigarettes have been marketed as a 'healthier' alternative to tobacco smoking, whilst product features have evolved tremendously in the meantime. A lively scientific debate has developed regarding the potential benefits and risks of e-cigarettes although, surprisingly, there are few studies investigating the addictive potential of nicotine-containing e-cigarettes. The present work comprises three work packages investigating the addictive potential of e-cigarettes from different perspectives: (1) the neurobiological addictive potential of e-cigarettes; (2) the experience and perception of dependence symptoms among users of e-cigarettes in a social context; and (3) the epidemiological perspective regarding factors influencing the potential for dependence.

METHODS

Work package I: the neurobiological study will investigate the key elements of addiction in e-cigarettes compared to tobacco cigarettes using neurobiological and neuropsychological correlates associated with craving, incentive motivation, cue reactivity and attentional bias. Work package II: the sociological study part examines self-reports on the experience and perception of dependence symptoms in a social context, using focus group interviews and the analysis of posts in online discussion forums on e-cigarettes. Work package III: the epidemiological study part focuses on tolerance development and the role of psychosocial and product factors by analyzing longitudinal data from the International Tobacco Control Policy Evaluation Project (ITC).

DISCUSSION

The present study offers a chosen mix of three methodological approaches, thereby comprehensively examining core symptoms of positive and negative reinforcement in addiction. Whether e-cigarettes are as reinforcing and addictive as combustible tobacco cigarettes is an important public health issue with implications for prevention and treatment programs.

TRIAL REGISTRATION

Work package I: Registered at clinicaltrials.gov/ct2/show/NCT04772014. Work package II: Registered at OSF Registries: https://osf.io/dxgya (2021, January 14).

Electronic nicotine delivery systems (ENDS) cue reactivity in dual users: A combined analysis

BACKGROUND

Cigarette smokers report increases in smoking urge in response to exposure to electronic nicotine delivery systems (ENDS) and dual users, i.e. smokers who also vape ENDS, may exhibit greater cue reactivity than exclusive smokers. The current investigation examined reactivity to a variety of ENDS cues across a large sample of cigarette smokers and dual ENDS users.

METHODS

Young adult smokers (N = 345; >5 cigarettes per day) were recruited between 2013-2019 for participation in a series of within-subjects laboratory-based studies. Participants completed surveys before and after exposure to a confederate-delivered control cue (water) and an active cue, including cigarette or ENDS cues ranging from first generation "cigalikes" to a fourth generation "pod-mod". Main outcomes were post-cue changes in desire for combustible cigarettes and e-cigarettes, and smoking behavior as determined by the smoking latency portion of the Smoking Lapse Paradigm after cue exposure.

RESULTS

Relative to smokers who do not use ENDS, dual users demonstrated higher baseline desire for ENDS and greater ENDS cue reactivity (across product types) in terms of post-cue increases in smoking urge and shorter latency to smoking choice. In contrast, reactivity to the cigarette cue was similar across groups.

CONCLUSIONS

Dual users show heightened ENDS cue reactivity on smoking urge and behavior relative to never users of ENDS, regardless of the type of ENDS cue. Given their reactivity to both cigarette and ENDS cues, it may be difficult for dual users to transition to exclusive vaping or quit tobacco product use altogether.

Combined smoking and alcohol cues: Effects on craving, drug-seeking, and consumption

BACKGROUND

Alcohol and cigarettes are commonly used together, but little is known about their joint motivational impact. Cue reactivity studies have customarily examined alcohol and smoking cues in isolation, despite the potential for cues to elicit stronger motivational responses when combined. This study used a validated cue reactivity procedure (Choice Behavior Under Cued Conditions) systematically to disentangle the separate and joint effects of alcohol and cigarette cues on substance use motivation.

METHODS

Participants were 110 adults (M_age  = 34.0, SD = 10.8) who consumed both cigarettes and alcohol. Participants completed 40 cue reactivity trials with four in vivo cue types: water, alcohol, cigarette, and combined cigarette and alcohol. Participants rated their craving prior to receiving opportunities to spend real money to gain access to the cues. Spending larger amounts of money increased the probability that the substance(s) would be available for consumption. When granted access, participants took one cigarette puff and/or sip of the beverage. A multimethod approach assessed three key motivational indices: craving, drug-seeking (spending, latency to access the cue), and consumption (puff duration, alcohol consumed). Effects of cue type and rates of substance use (cigarettes per day, drinks per day, relative frequency of co-use) were assessed using hierarchical linear models.

RESULTS

Both alcohol and smoking cues enhanced cue-specific craving but not craving for the alternative substance. In a novel finding, combined cues elicited higher craving and greater spending than single-drug cues. All drug cues elicited greater spending than water cues, and spending was moderated by the relative frequency of co-use.

CONCLUSIONS

We found that combined alcohol and cigarette cues provoke more powerful craving and drug-seeking responses and, therefore, may be more motivationally potent among individuals who use multiple substances.

The impact of three weeks of pre-quit varenicline on reinforcing value and craving for cigarettes in a laboratory choice procedure

RATIONALE

Varenicline, a partial nicotinic agonist, is theorized to attenuate pre-quit smoking reinforcement and post-quit withdrawal and craving. However, the mechanisms of action have not been fully characterized, as most studies employ only retrospective self-report measures, hypothetical indices of reinforcing value, and/or nontreatment-seeking samples.

OBJECTIVES

The current research examined the impact of pre-quit varenicline (vs. placebo) on laboratory measures of smoking and food (vs. water) reinforcement and craving.

METHODS

Participants were 162 treatment-seeking smokers enrolled in a randomized controlled trial of smoking cessation ( clinicaltrials.gov ID: NCT03262662). Participants completed two laboratory sessions: a pre-treatment session, ~ 1 week prior to beginning varenicline or placebo, and an active treatment session, after ~ 3 weeks of treatment. At each session, participants completed a laboratory choice procedure; on each of 36 trials, a lit cigarette, food item, or cup of water was randomly presented. Participants reported level of craving and spent $0.01-0.25 to have a corresponding 5-95% chance to sample the cue.

RESULTS

As predicted, spending was significantly higher on cigarette trials than water trials, and varenicline resulted in a greater between-session decline in spending on cigarette trials (but not water) than did placebo. Cigarette craving was enhanced in the presence of smoking cues compared to water, but neither average (tonic) cigarette craving nor cue-specific cigarette craving was significantly influenced by varenicline. Food spending and craving were generally unaffected by varenicline treatment.

CONCLUSIONS

These laboratory data from treatment-seeking smokers provide the strongest evidence to date that varenicline selectively attenuates smoking reinforcement prior to quitting.

Assessment of the Choice Behavior Under Cued Conditions (CBUCC) paradigm as a measure of motivation to smoke under laboratory conditions

BACKGROUND AND AIMS

The Choice Behavior under Cued Conditions (CBUCC) task uses three indices of tobacco use (consumption, money spent to access a cigarette and latency to reach for a cigarette) to assess motivation to smoke under laboratory conditions. Initial research with this procedure has shown that it can evince cue-specific craving and differential responding for smoking versus a neutral cue. This study aimed to replicate these findings and assess the interaction of cue-specific craving and behavior with abstinence prior to testing.

DESIGN

A mixed repeated-measures between-groups factorial design was used. Participants attended a morning laboratory session in which they were randomized to remain abstinent or smoke as usual (between-groups factor) and returned in the afternoon to complete CBUCC. In this, participants were exposed to 40 experimental trials. In each trial they were exposed to a cigarette or water cue behind a movable glass door (repeated-measures factor).

SETTING

University at Buffalo, New York, USA.

PARTICIPANTS

Participants were 106 daily non-treatment-seeking cigarette smokers, data from 102 were used.

MEASUREMENTS

On each of 40 trials, participants rated cigarette craving, and behavioral measures from the CBUCC (money spent, latency to access the cue, puff duration) were recorded.

FINDINGS

Craving and CBUCC behavioral measures showed high internal reliability across trials (Cronbach alphas ranged from 0.88 to 0.98). Craving and money spent were higher in trials with the cigarette cue than the water cue (F₍₁₁₀₀₎  = 45.49, P < 0.001 and F₍₁₁₀₀₎  = 116.26, P < 0.001). Other CBUCC measures did not show a significant effect of cue type. The difference in spending between cigarette and water cues was larger for abstinent participants than non-abstinent participants (F₍₁₁₀₀₎  = 5.0, P = 0.03). Other CBUCC measures did not show a significant interaction between abstinence and cue type. Craving on smoking trials was significantly correlated with cigarette spending (r = 0.54, P < 0.001) in the non-abstinence condition but not in the abstinence condition.

CONCLUSIONS

Craving and 'money spent' in the Choice Behavior under Cued Conditions task (CBUCC) appears to be responsive to cigarette versus water cues, and money spent appears to show greater difference in responsiveness to cigarette than water cues after abstinence.