Addiction Potential of Cigarettes With Reduced Nicotine Content in Populations With Psychiatric Disorders and Other Vulnerabilities to Tobacco Addiction

Racial/ethnic differences in the acute effects of reduced nicotine content cigarettes among adolescents who smoke

OBJECTIVE

Reducing the nicotine content in cigarettes decreases their addictiveness and abuse liability, including among adolescents. Whether these effects differ by race/ethnicity is unknown. This study is a secondary analysis of previously published data collected between 2014-2017. We examined racial/ethnic differences in the effects of smoking cigarettes with varying nicotine content levels on subjective effects and tobacco withdrawal among adolescents who smoke daily.

METHODS

Across two counterbalanced sessions, 50 adolescents recruited from Rhode Island (ages 15-19; 30 % Underrepresented Minorities [URM], 20 % Asians and Pacific Islanders [API]; 50 % Non-Hispanic Whites) self-administered a very low nicotine content (VLNC; 0.4 mg nicotine/g of tobacco) or normal nicotine content control (NNC; 15.8 mg/g) research cigarette following overnight abstinence. Subjective effects were reported post-administration and tobacco withdrawal outcomes were calculated from pre- to post-administration scores. Multilevel linear models tested main and interactive effects between cigarette nicotine content and race/ethnicity on all study outcomes.

RESULTS

Participants reported lower positive subjective effects and reductions in smoking urges after smoking a VLNC cigarette relative to smoking an NNC cigarette (ps < 0.01). A main effect of race/ethnicity emerged, such that API (vs. URM and White) adolescents reported lower positive subjective effects, greater craving reduction, and higher cigarette aversion after smoking, regardless of nicotine content (ps < 0.05). Significant interactions were found between race/ethnicity and nicotine content for cigarette aversion, such that API adolescents rated VLNC (vs. NNC) cigarettes as less aversive than White and URM adolescents did (p = 0.03).

CONCLUSIONS

Findings provide evidence that VLNC cigarettes may reduce abuse liability and tobacco withdrawal symptoms for adolescents across racial/ethnic groups and particularly for API youth.

Reduced Nicotine Cigarettes and E-Cigarettes in High-Risk Populations: 3 Randomized Clinical Trials

Importance

Prohibiting the sale of commonly preferred e-cigarette flavors (eg, fruity and sweet) to discourage use among youths poses a risk of diminishing efforts to decrease smoking in adults.

Objective

To compare reductions in smoking achieved in adults with psychiatric conditions or lower educational level using very low nicotine content (VLNC) cigarettes alone, combined with e-cigarettes limited to tobacco flavor (TF), or combined with e-cigarettes in participant-preferred flavors.

Design, Setting, and Participants

Three randomized clinical trials were conducted for 16 weeks from October 2020 through November 2023 at the University of Vermont, Brown University, and Johns Hopkins University. Participants were adults who smoked daily and were not planning to quit in the next 30 days. These participants were from 3 at-risk populations: those with affective disorders, exemplifying mental illness; those with opioid use disorder, exemplifying substance use disorders; and females of reproductive age with a high-school education or less, exemplifying lower educational level. Participants were randomly assigned to 1 of 4 experimental conditions: (1) normal nicotine content (NNC) cigarettes only; (2) VLNC cigarettes only; (3) VLNC cigarettes plus e-cigarettes with classic TF (hereafter, VLNC + TF); and (4) VLNC cigarettes plus e-cigarettes with preferred flavors (hereafter, VLNC + PF).

Interventions

The NNC cigarettes contained 15.8 mg nicotine/g tobacco, the VLNC cigarettes contained 0.4 mg nicotine/g tobacco, the VLNC + TF had pods containing 5% nicotine by weight and only classic TF, and the VLNC + PF had pods containing 5% nicotine in 8 flavors (including fruity and sweet) from which participants selected 3 flavors.

Main Outcomes and Measures

The primary outcome was mean total cigarettes smoked per day (CPD) during week 16. Tobacco-related biomarkers were assessed, including total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a tobacco-specific carcinogen.

Results

A total of 326 participants (mean [SD] age, 40.09 [10.79] years; 243 females [74.5%]) from 3 randomized clinical trials were included. The VLNC cigarettes decreased total CPD, with least square (LS) means (SEMs) of 22.54 (1.59) in the NNC, 14.32 (1.32) in the VLNC, 11.76 (1.18) in the VLNC + TF, and 7.63 (0.90) in the VLNC + PF conditions. Each VLNC condition differed significantly from NNC, with an adjusted mean difference (AMD) of -8.21 (95% CI, -12.27 to -4.16; P < .001) in the VLNC, -10.78 (95% CI, -14.67 to -6.90; P < .001) in the VLNC + TF, and -14.91 (95% CI, -18.49 to -11.33; P < .001) in the VLNC + PF conditions. Participants in the VLNC + PF condition also decreased smoking below the VLNC and the VLNC + TF conditions (AMDs, -6.70 [95% CI, -9.84 to -3.55; P < .001] and -4.13 [95% CI, -7.05 to -1.21; P = .02]); the VLNC and VLNC + TF conditions did not differ significantly. Consistent with decreases in CPD, NNAL levels in the VLNC + PF condition were lower than in all other conditions, with AMDs (in pmol/mg creatinine) of -0.94 (95% CI, -1.41 to -0.47; P < .001) compared with the NNC condition, -0.47 (95% CI, -0.87 to -0.08; P = .03) compared with the VLNC condition, and -0.46 (95% CI, -0.83 to -0.10; P = .04) compared with the VLNC + TF condition.

Conclusions and Relevance

These results provide further evidence that a reduced-nicotine standard for cigarettes has the potential to decrease smoking and tobacco-toxicant exposure in high-risk populations and that these effects may be enhanced when adults can access e-cigarettes in commonly preferred flavors.

Trial Registration

ClinicalTrials.gov Identifiers: NCT04092387, NCT04090879, NCT04092101.

Associations between compliance with very low nicotine content (VLNC) cigarettes, abstinence self-efficacy, and quit outcomes in a pilot smoking cessation trial

BACKGROUND

Switching to Very Low Nicotine Content (VLNC) cigarettes reduces toxicant exposure and nicotine dependence, and may improve smoking cessation. However, non-compliance with VLNCs is often high, which may reduce their effectiveness. Here, we conducted secondary analyses of a pilot smoking cessation trial utilizing VLNCs to examine associations between pre-cessation VLNC compliance and changes in smoking rate, dependence, and abstinence self-efficacy, as well as quit outcomes.

METHODS

People who smoke daily (n=35) engaged in a 4-week pre-cessation intervention including VLNCs, transdermal nicotine patch, and behavioral counseling. After quit date, participants received 8 weeks of nicotine replacement therapy and 4 additional behavioral sessions, and were followed for 10 weeks to assess abstinence. Compliance with VLNCs was assessed biweekly during pre-cessation using timeline follow-back. Statistical analyses examined associations between VLNC compliance and a) changes in smoking rate, dependence and abstinence self-efficacy over the course of study cigarette use; and b) time to relapse, controlling for other smoking variables.

RESULTS

Greater compliance during the second half of study cigarette use was associated with subsequent improvement in self-efficacy (p<.05). Increased self-efficacy and VLNC compliance both predicted lower likelihood of relapse. Nicotine dependence and cigarettes per day both decreased following study cigarette use, but were unrelated to compliance or relapse.

CONCLUSIONS

Compliance with VLNCs prior to quitting increased abstinence self-efficacy and predicted better quit outcomes above and beyond baseline smoking characteristics. Although preliminary, these findings suggest that identifying strategies to promote exclusive use of VLNCs during a brief pre-cessation window may be beneficial.

Examining the predictive utility of behavioral economic demand indices and subjective effects on the actualized reinforcing value of menthol cigarettes and potential alternatives

INTRODUCTION

Considering recent and proposed bans on menthol cigarettes, methods are needed to understand the substitutability of potential menthol cigarette alternatives (MCAs) for menthol cigarettes. This study examined the prospective relationship between behavioral economic demand indices and subjective effects of usual brand menthol cigarettes (UBMC) and preferred MCAs with subsequent performance on a laboratory-based concurrent-choice task comparing UBMC and MCAs.

METHODS

Eighty participants who typically smoked menthol cigarettes completed this clinical lab study. After sampling each product, participants completed the cigarette purchase task (CPT) and modified cigarette evaluation questionnaire (mCEQ). Following one-week of substituting their preferred MCA for their UBMC, participants completed a 90-min concurrent-choice self-administration task comparing their UBMC and preferred MCA. Linear regression models explored associations between CPT demand indices and mCEQ subjective effects in the lab with subsequent response effort for UBMCs on the concurrent-choice task.

RESULTS

Three demand indices for UBMC were positively associated with UBMC response effort: Essential Value (EV; p=.02), Omax (p=.02), and breakpoint (p=.04). Four CPT demand indices for the preferred MCA significantly corresponded with UBMC response effort: EV (p=.03), Pmax (p=.04), Omax (p=.03), and breakpoint (p=.03). Subjective effects captured by the mCEQ were not associated with response effort.

CONCLUSIONS

Demand indices reflecting Persistence (i.e., sensitivity to escalating price) predicted effort to obtain UBMC puffs on the concurrent-choice task. Among this sample, the CPT captured information on the relative reinforcing value (i.e., addiction potential) of combustible tobacco products similar to the longer self-administration task.

IMPLICATIONS

In an ever-changing product market, assessing the reinforcing efficacy of menthol cigarettes and putative substitutes quickly and with validity is an important methodological tool for understanding abuse liability. Results suggest that behavioral economic demand indices of cigarette purchase task efficiently capture information on the relative reinforcing value of usual brand menthol cigarettes and plausible alternative tobacco products, similar to a 90-min in-laboratory self-administration task.

Addiction potential of combustible menthol cigarette alternatives: a randomised cross-over trial

INTRODUCTION

The Food and Drug Administration (FDA) has issued proposed product standards banning menthol as a characterising flavour in cigarettes and cigars. The public health benefits of these product standards may be attenuated by the role of plausible substitutes in the marketplace. Therefore, the present study examined the addiction potential of plausible combustible menthol alternatives compared with usual brand menthol cigarettes (UBMC).

METHODS

Ninety-eight adult menthol cigarette smokers completed four visits, smoking their UBMC at the first session and three menthol cigarette alternatives in random order at the subsequent visits: (1) a preassembled menthol roll-your-own (mRYO) cigarette using menthol pipe tobacco and mentholated cigarette tube, (2) a menthol filtered little cigar (mFLC) and (3) a non-menthol cigarette (NMC). Measures of smoking topography, exhaled carbon monoxide (CO), craving and withdrawal, subjective effects and behavioural economic demand indices were assessed.

RESULTS

Compared with UBMC, menthol cigarette alternatives resulted in different puffing topography and CO exposure (except mRYO), and lower levels of positive subjective experience and behavioural economic demand indices. Among the alternative products, participants reported the highest level of positive subjective experience and higher demand for mRYO, compared with mFLC and NMC. Similarly, participants were significantly more likely to want to try again, purchase and use the mRYO product regularly compared with mFLC and NMC.

CONCLUSIONS AND RELEVANCE

mRYO cigarettes were the most highly rated cigarette alternative among study products, suggesting their potential appeal as a menthol cigarette substitute and needed inclusion of menthol pipe tobacco and cigarette tubes in FDA's proposed ban.

Multidimensional assessment of the biological effects of electronic cigarettes on lung bronchial epithelial cells

Cigarette smoke (CS) exposure is known to cause injury to respiratory tract epithelial cells and is a contributing factor in the development of chronic obstructive pulmonary disease and lung cancer. Electronic cigarettes (e-cigarettes) are gaining popularity as a potential substitute for conventional cigarettes due to their potential for aiding smoking cessation. However, the safety of e-cigarettes remains uncertain, and scientific evidence on this topic is still limited. In this study, we aimed to investigate the effects of CS and e-cigarette smoke (ECS) of different flavors on human lung bronchial epithelial cells. Real-time smoke exposure was carried out using an air-liquid interface system, and cell viability was assessed. RNA-Seq transcriptome analysis was performed to compare the differences between CS and ECS. The transcriptome analysis revealed a significantly higher number of differentially expressed genes in CS than in ECS. Moreover, the impact of mint-flavored e-cigarettes on cells was found to be greater than that of tobacco-flavored e-cigarettes, as evidenced by the greater number of differentially expressed genes. These findings provide a reference for future safety research on traditional cigarettes and e-cigarettes, particularly those of different flavors. The use of omics-scale methodologies has improved our ability to understand the biological effects of CS and ECS on human respiratory tract epithelial cells, which can aid in the development of novel approaches for smoking cessation and lung disease prevention.

Exploring the Link between Altitude of Residence and Smoking Patterns in the United States

INTRODUCTION

Smoking-related diseases affect 16 million Americans, causing approximately 480,000 deaths annually. The prevalence of cigarette smoking varies regionally across the United States, and previous research indicates that regional rates of smoking-related diseases demonstrate a negative association with altitude. The purpose of this study was to determine the relationship between altitude and the prevalence of cigarette smoking by county (N = 3106) in the United States. We hypothesized that smoking prevalence among adults would be negatively associated with mean county altitude.

METHODS

A multivariate linear regression was performed to examine the relationship between county-level mean altitude and county smoking rate. Covariates were individually correlated with 2020 smoking data, and significant associations were included in the final model.

RESULTS

The multivariate linear regression indicated that the county-level smoking rates are significantly reduced at high altitudes (p < 0.001). The model accounted for 89.5% of the variance in smoking prevalence, and for each 1000-foot increase in altitude above sea level, smoking rates decreased by 0.143%. Based on multivariate linear regression, the following variables remained independently and significantly associated: race, sex, educational attainment, socioeconomic status, unemployment, physical inactivity, drinking behavior, mental distress, and tobacco taxation.

CONCLUSIONS

Our results indicate that smoking rates are negatively associated with altitude, which may suggest that altitude affects the pharmacokinetics, pharmacodynamics, and mechanistic pathways involved in cigarette use. Further research is needed to explore the relationship between altitude and smoking and how altitude may serve as a protective factor in the acquisition and maintenance of tobacco use disorders.

Nicotine and Cardiovascular Health: When Poison is Addictive - a WHF Policy Brief

Nicotine is universally recognized as the primary addictive substance fuelling the continued use of tobacco products, which are responsible for over 8 million deaths annually. In recent years, the popularity of newer recreational nicotine products has surged drastically in many countries, raising health and safety concerns. For decades, the tobacco industry has promoted the myth that nicotine is as harmless as caffeine. Nonetheless, evidence shows that nicotine is far from innocuous, even on its own. In fact, numerous studies have demonstrated that nicotine can harm multiple organs, including the respiratory and cardiovascular systems. Tobacco and recreational nicotine products are commercialized in various types and forms, delivering varying levels of nicotine along with other toxic compounds. These products deliver nicotine in profiles that can initiate and perpetuate addiction, especially in young populations. Notably, some electronic nicotine delivery systems (ENDS) and heated tobacco products (HTP) can deliver concentrations of nicotine that are comparable to those of traditional cigarettes. Despite being regularly advertised as such, ENDS and HTP have demonstrated limited effectiveness as tobacco cessation aids in real-world settings. Furthermore, ENDS have also been associated with an increased risk of cardiovascular disease. In contrast, nicotine replacement therapies (NRT) are proven to be safe and effective medications for tobacco cessation. NRTs are designed to release nicotine in a slow and controlled manner, thereby minimizing the potential for abuse. Moreover, the long-term safety of NRTs has been extensively studied and documented. The vast majority of tobacco and nicotine products available in the market currently contain nicotine derived from tobacco leaves. However, advancements in the chemical synthesis of nicotine have introduced an economically viable alternative source. The tobacco industry has been exploiting synthetic nicotine to circumvent existing tobacco control laws and regulations. The emergence of newer tobacco and recreational nicotine products, along with synthetic nicotine, pose a tangible threat to established tobacco control policies. Nicotine regulations need to be responsive to address these evolving challenges. As such, governments should regulate all tobacco and non-medical nicotine products through a global, comprehensive, and consistent approach in order to safeguard tobacco control progress in past decades.

Effect of nicotine expectancy and nicotine dose reduction on cigarette demand, withdrawal alleviation, and puff topography

BACKGROUND

Current FDA plans include proposed nicotine reduction mandates by the end of 2023. Most research on reduced nicotine cigarettes has been dose-blinded, while a mandate would be known to the public. Few laboratory studies have examined specifically how low nicotine content labeling impacts behavioral response. The purpose of this within-subject, balanced-placebo, human laboratory study was to evaluate the main and interactive effects of nicotine dose expectancy and dose reduction on cigarette reinforcement, withdrawal alleviation, and puff topography.

METHODS

Participants who smoke daily (N=21; 9 female) completed one practice and four experimental sessions in which expectancy (labeled "average" versus "very low" nicotine) and nicotine dose (0.80mg versus 0.03mg yield) were manipulated. Participants in acute withdrawal sampled experimental cigarettes followed by withdrawal alleviation and puff topography measures. Cigarette demand was measured using an incentivized purchase task. Analyses evaluated main and interactive effects of expectancy and nicotine dose.

RESULTS

Nicotine dose manipulation produced expected physiological effects (e.g., heart rate increases) and both reduced nicotine dose and expectation manipulations reduced perceived nicotine content. Expectation of reduced nicotine alone or in combination with reduced nicotine dose did not alter demand, withdrawal alleviation, or topography. Effective withdrawal alleviation was observed in all conditions.

CONCLUSIONS

These data inform nicotine regulation policy by suggesting limited compensatory harms caused by reduced nicotine expectations. The minimal acute effects of reduced nicotine expectancy or exposure on demand suggests that reduced nicotine standards are likely to generate their greatest public health benefit through the slowing of newly initiating cigarette smoking.

E-cigarette Price Impacts legal and Black-Market Cigarette Purchasing Under a Hypothetical Reduced-Nicotine Cigarette Standard

INTRODUCTION

The Tobacco Control Act gives the U.S. Food and Drug Administration authority to establish a reduced-nicotine content standard in combusted cigarettes. This future potential regulation may pose a significant public health benefit; however, black markets may arise to meet demand for normal-nicotine content cigarettes among smokers unwilling to transition to or use an alternative product.

AIMS AND METHODS

We determined the behavioral-economic substitutability of illicit normal-nicotine content cigarettes and e-cigarettes for reduced-nicotine content cigarettes in a hypothetical reduced-nicotine regulatory market. Adult cigarette smokers were recruited online to complete hypothetical cigarette purchasing tasks for usual-brand cigarettes, reduced-nicotine content cigarettes, and illicit normal-nicotine content cigarettes, as well as a cross-commodity task in which reduced-nicotine content cigarettes were available across multiple prices and illicit cigarettes were concurrently available for $12/pack. Participants completed two three-item cross-commodity purchasing tasks in which e-cigarettes were available for $4/pod or $12/pod alongside reduced-nicotine content cigarettes and illicit cigarettes.

RESULTS

Usual-brand cigarette purchasing was greater than illicit normal-nicotine content cigarettes and less than reduced-nicotine content cigarettes. In the cross-commodity purchasing tasks, illicit cigarettes and e-cigarettes both served as economic substitutes for reduced-nicotine content cigarettes; however, when e-cigarettes were available for $4/pod, they were purchased at greater levels than illicit cigarettes and resulted in greater reductions in reduced-nicotine content cigarettes purchasing than when available for $12/pod.

CONCLUSIONS

These data suggest that some smokers are willing to engage in illicit cigarette purchasing in a reduced-nicotine regulatory environment, but e-cigarette availability at lower prices may reduce black-market engagement and shift behavior away from combusted cigarette use.

IMPLICATIONS

E-cigarettes available at low, but not high, prices were stronger substitutes for legal, reduced-nicotine content cigarettes than illegal, normal-nicotine content cigarettes in a hypothetical reduced-nicotine tobacco market. Our findings suggest the availability of relatively inexpensive e-cigarettes may reduce illicit cigarette purchasing and combusted cigarette use under a reduced-nicotine cigarette standard.

Concurrent Choice Assessment of Preference and Substitutability of E-cigarettes and Heated Tobacco Products for Combustible Cigarettes Among African American and White Smokers

INTRODUCTION

Alternative nicotine delivery products, including electronic cigarettes (e-cigarettes) and heated tobacco products (HTPs), contain fewer toxicants than combustible cigarettes and offer a potential for harm reduction. Research on the substitutability of e-cigarettes and HTPs is crucial for understanding their impact on public health. This study examined subjective and behavioral preferences for an e-cigarette and HTP relative to participants' usual brand combustible cigarette (UBC) in African American and White smokers naïve to alternative products.

AIMS AND METHODS

Twenty-two adult African American (n = 12) and White (n = 10) smokers completed randomized study sessions with their UBC and study provided e-cigarette and HTP. A concurrent choice task allowed participants to earn puffs of the products but placed UBC on a progressive ratio schedule, making puffs harder to earn, and e-cigarette and HTP on a fixed ratio schedule to assess behavioral preference for the products. Behavioral preference was then compared to self-reported subjective preference.

RESULTS

Most participants had a subjective preference for UBC (n = 11, 52.4%), followed by an equal preference for e-cigarette (n = 5, 23.8%) and HTP (n = 5, 23.8%). During the concurrent choice task, participants showed a behavioral preference (i.e., more earned puffs) for the e-cigarette (n = 9, 42.9%), followed by HTP (n = 8, 38.1%), and UBC (n = 4, 19.1%). Participants earned significantly more puffs of the alternative products compared to UBC (p = .011) with no difference in earned puffs between e-cigarettes and HTP (p = .806).

CONCLUSIONS

In a simulated lab setting, African American and White smokers were willing to substitute UBC for an e-cigarette or HTP when the attainment of UBC became more difficult.

TRIAL REGISTRATION

NCT04646668.

IMPLICATIONS

Findings suggest that African American and White smokers are willing to substitute their UBC for an alternative nicotine delivery product (e-cigarette or HTP) when the attainment of cigarettes became more difficult in a simulated lab setting. Findings require confirmation among a larger sample under real-world conditions but add to growing evidence suggesting the acceptability of alternative nicotine delivery products among racially diverse smokers. These data are important as policies that limit the availability or appeal of combustible cigarettes are considered or enacted.

Impact of reduced nicotine content on behavioral economic measures of cigarette reinforcement in adolescents who smoke cigarettes

BACKGROUND

Public health officials in the U.S. and New Zealand are considering a reduced nicotine standard for cigarettes to reduce their addictive potential. This study's aim was to evaluate the effects of nicotine reduction on the reinforcing efficacy of cigarettes in adolescents who smoke, which has implications for this policy's potential for success.

METHODS

Adolescents who smoked cigarettes daily (n = 66; mean age: 18.6) participated in a randomized clinical trial assessing effects of assignment to very low nicotine content (VLNC; 0.4 mg/g nicotine) or normal nicotine content (NNC; 15.8 mg/g nicotine) cigarettes. Hypothetical cigarette purchase tasks were completed at baseline and the end of Week 3 and demand curves fit to the data. Linear regressions estimated effects of nicotine content on demand for study cigarettes at baseline and Week 3 and associations between baseline demand for cigarette consumption at Week 3.

RESULTS

An extra sum of squares F-test of fitted demand curves indicated that demand (α) was more elastic among VLNC participants at baseline and Week 3 (F(2, 1016)= 35.72, p < 0.001). Adjusted linear regressions indicated demand was more elastic (ß= 1.45, p < 0.01) and maximum expenditure (Omax) lower (ß= -1.42, p-0.03) among VLNC participants at Week 3. More elastic demand for study cigarettes at baseline predicted lower consumption of cigarettes at Week 3 (p's < 0.01).

CONCLUSIONS

A nicotine reduction policy may reduce the reinforcing value of combustible cigarettes among adolescents. Future work should investigate likely responses to such a policy among youth with other vulnerabilities and evaluate the potential for substitution to other nicotine containing products.

The Impact of Reducing Nicotine Content on Adolescent Cigarette Smoking and Nicotine Exposure: Results From a Randomized Controlled Trial

INTRODUCTION

As the science base around the potential benefits of a reduced-nicotine standard for cigarettes grows, information on the potential effects on adolescent smokers is a high priority. The aim of this randomized trial was to test the influence of 3-week exposure to reduced nicotine cigarettes in a sample of adolescent daily smokers.

AIMS AND METHODS

In this double-blind, two-arm, randomized controlled trial (NCT0258731), following a 1-week baseline, adolescent daily smokers not currently intending to quit (ages 15-19 years, n = 66 randomized) were urn randomized to use either very low nicotine content (VLNC; 0.4 mg/g; n = 33) or normal nicotine content (NNC, 15.8 mg/g; n = 33) research cigarettes for 3 weeks. Participants attended five study sessions at our clinical laboratory. The primary outcome was average total cigarettes smoked per day (CPD; including both study and non-study cigarettes) at week 3.

RESULTS

Stepwise regression results demonstrated that compared with NNC cigarettes (n = 31), assignment to VLNC cigarettes (n = 29), was associated with 2.4 fewer CPD on average than NNC assignment (p < .05) week 3 when controlling for covariates (p < .01, Cohen's d = 0.52 n = 60 completed all procedures). VLNC cigarettes were also associated with lower levels of craving reduction than NNC cigarettes (Questionnaire on Smoking Urges Factor 2, p < .05). No group differences were found for secondary outcomes.

CONCLUSIONS

Adolescent participants assigned to VLNC use for 3 weeks smoked fewer total CPD relative to the NNC group. Overall, data suggest that a VLNC policy would reduce cigarette smoking in adolescents who smoke, but high rates of incomplete adherence suggest that youth may seek alternative sources of nicotine in this scenario.

IMPLICATIONS

The US Food and Drug Administration may enact a reduced-nicotine product standard that would affect all commercially available cigarettes. One important population affected by this policy would be adolescents who smoke. This study, the first clinical trial of VLNC cigarettes in adolescents, demonstrates that adolescents switched to VLNC cigarettes for 3 weeks reduced their CPD relative to the normal-nicotine cigarette control group, without leading to increased respiratory symptoms or increased withdrawal. Biomarkers indicated the use of other sources of nicotine, suggesting that such a policy will need to consider approaches to assist in transitioning away from smoking.

Manipulation of Menthol and Nicotine Content in Cigarettes: Effects on Smoking Behavior and Toxicant Exposure in Women Menthol Smokers

BACKGROUND

The purpose of this study was to determine the effects of smoking and other outcomes of assigning cigarettes with reduced nicotine and/or no menthol to female menthol smokers.

AIMS AND METHODS

Nontreatment-seeking female menthol smokers (N = 263) participated in a randomized controlled trial in which levels of menthol and nicotine in cigarettes were manipulated using experimental cigarettes. After a baseline period, participants were assigned to the following conditions for 6 weeks: (1) their own brand of cigarette (conventional nicotine with menthol), (2) a conventional nicotine cigarette with no menthol, (3) a cigarette with reduced nicotine (RNC) with menthol, or (4) a RNC cigarette and no menthol. Participants then returned to using their own brand and were followed for another 6 weeks. Outcomes included cigarettes smoked, biomarkers of exposure, and dependence measures.

RESULTS

Results indicated that, after an initial increase, rates of smoking of all three experimental cigarettes were at or below baseline rates of smoking of one's own brand. Levels of biomarkers also decreased during the experimental phase but rebounded somewhat after participants resumed smoking their own brand. There was evidence that the overall amount of smoking decreased similarly among women who switched to non-menthol and/or RNC cigarettes.

CONCLUSIONS

These results suggest that no detrimental effect will occur in nicotine or toxicant exposure levels with a ban on characterizing menthol and/or a product standard on nicotine content in cigarettes.

IMPLICATIONS

The implication of this work is that there would be no risk to women menthol smokers associated with regulations restricting nicotine and eliminating menthol in cigarettes.

Examining the latent factor structure of a hypothetical cigarette purchase task among pregnant women

The cigarette purchase task (CPT) is a valid behavioral-economic measure of demand that has smokers estimate hypothetical cigarette consumption under a range of escalating prices. The task involves no experimenter exposure of participants to smoking. CPT demand is measured in terms of five indices: intensity (cigarettes consumed at $0), Omax (largest expenditure), Pmax (price associated with peak expenditure), breakpoint (the first price at which consumption is 0), and elasticity (rate at which consumption changes as a function of increasing price). Out of concern for collinearity, prior studies investigated a more parsimonious CPT latent-factor structure for these derived indices consisting of two factors. The present study examined whether the same two latent-factor solutions extend to pregnant women who smoke. Six hundred sixty-five women completed the CPT as part of recruitment for a clinical trial examining the efficacy of a remote contingency-management intervention to promote smoking cessation during pregnancy. Factor analysis confirmed a two-factor solution to the CPT accounting for 87% of the variance in the five indices with demand intensity and Omax loading onto amplitude and Omax, Pmax, breakpoint, and elasticity loading onto persistence. Backward elimination regression revealed a significant negative relationship between amplitude and persistence (i.e., lower amplitude and persistence scores predicted a higher likelihood of making at least one quit attempt upon learning of pregnancy). These results further support the utility of the CPT for experimentally examining individual differences in smoking among pregnant women in an efficient and ethical manner that does not involve exposing them to cigarette smoke. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Tobacco endgame and priority populations: a scoping review

AIM

To summarise the research literature on the impacts or perceptions of policies to end tobacco use at a population level (ie, tobacco endgame policies) among people from eight priority population groups (experiencing mental illness, substance use disorders, HIV, homelessness, unemployment or low incomes, who identify as lesbian, gay, bisexual, transgender, queer or intersex (LGBTQI+) or who have experienced incarceration).

METHODS

Guided by JBI Scoping Review Methodology, we searched six databases for original research examining the impacts or perceptions of 12 tobacco endgame policies among eight priority populations published since 2000. We report the results according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist.

RESULTS

Of the 18 included studies, one described perceptions of five endgame policies among people on low incomes in Aotearoa (New Zealand), and 17 focused on the effectiveness or impacts of a very low nicotine content (VLNC) cigarette standard among people experiencing mental illness (n=14), substance use disorders (n=8), low incomes (n=6), unemployment (n=1) or who identify as LGBTQI+ (n=1) in the USA. These studies provide evidence that VLNC cigarettes can reduce tobacco smoking, cigarette cravings, nicotine withdrawal and nicotine dependence among these populations.

CONCLUSIONS

Most of the tobacco endgame literature related to these priority populations focuses on VLNC cigarettes. Identified research gaps include the effectiveness of endgame policies for reducing smoking, impacts (both expected and unexpected) and policy perceptions among these priority populations.

Using an experimental tobacco marketplace to pilot test the substitutability of JUUL e-cigarettes and other alternative nicotine and tobacco products for conventional cigarettes among vulnerable populations

The Experimental Tobacco Marketplace (ETM) is an online research marketplace where increasing the cost of cigarettes is used to investigate the substitutability of other fixed-price tobacco products such as electronic nicotine delivery systems (ENDS). The ETM is useful for modeling effects of potential policy changes on use of various concurrently available products. To our knowledge, the ETM has not been used to investigate substitutability of newer generation e-cigarettes or populations at increased risk for smoking, heavy smoking, nicotine dependence, and smoking-attributable adverse effects. In the current pilot study, participants were 30 adult daily smokers with socioeconomic disadvantage or comorbid psychiatric conditions (substance-use disorder or mental illness). In each session, cigarette prices increased ($0.12, $0.25, $0.50, $1.00. and $2.00 per cigarette) while prices for alternative products remained fixed. Across three ETM sessions, either all products, all products except little cigars and cigarillos (LCCs), or all products except ENDS (JUUL e-cigarettes) were available. Linear regression was performed on individual participant data using log-transformed cigarette price to determine demand and substitution. Cigarette demand decreased as price increased across sessions (significantly non-zero slopes, ps ≤ 0.0001). When all products were available, ENDS substitution increased as cigarette price increased (significantly non-zero slope, p = .016). When LCCs were unavailable, ENDS again were a significant substitute (p = .008). When ENDS were unavailable, LCCs did not substitute (ps ≥ 0.48). In all sessions, participants rarely purchased other products (e.g., snus). Overall, ENDS were the most robust substitute for cigarettes, further underscoring the potential importance of ENDS availability on the impact of tobacco regulatory policies.

Effect of brief nicotine corrective messaging on nicotine beliefs in persons who use opioids

This pilot study tested the effect of a brief nicotine education messaging exposure on beliefs about nicotine, nicotine-replacement therapy (NRT), and e-cigarettes. Participants ages 18 and older were recruited via Amazon Mechanical Turk to complete a 20-min online survey in April/May 2020 to assess relationships between opioid use, smoking, and other behaviors. Participants with past-month extra-medical opioid use completed questions on background characteristics and literacy and then were randomized in a 2:1 ratio of two conditions: nicotine education (n = 362) or no message control (n = 181). Beliefs about nicotine, NRT, and e-cigarettes were asked of all participants; this occurred after message exposure for the nicotine education condition. Bivariate and multivariable analyses examined differences in beliefs by study condition. Brief nicotine messaging increased the probability of a correct response to "Nicotine is a cause of cancer" (false, 63% vs. 36%) and reduced the probability of a don't know response (9% vs. 17%) compared to the no message control condition. Nicotine education also reduced false beliefs about harms of long-term NRT use compared to cigarettes (p < .05). In adjusted models, participants in the nicotine education group had lower mean false beliefs about nicotine (p < .001) and to a lesser extent NRT (p = .053) compared with the control group; there was no difference in mean false beliefs about e-cigarettes (p = .547) between groups. A brief education intervention produced similar changes in nicotine beliefs in adults with past-month extra-medical opioid use as in a general adult sample. Findings support the potential for impact of nicotine public education messaging in vulnerable populations. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Potential effects of nicotine content in cigarettes on use of other substances

A national nicotine reduction policy has the potential to reduce cigarette smoking and associated adverse health impacts among vulnerable populations. However, possible unanticipated adverse effects of reducing nicotine content in cigarettes, such as increasing the use of alcohol or other abused substances, must be examined. The purpose of this study was to evaluate the effects of exposure to varying doses of nicotine in cigarettes on use of other substances. This was a secondary analysis (n = 753) of three simultaneous, multisite, double-blind, randomized-controlled trials examining 12 weeks of exposure to study cigarettes varying in nicotine content (0.4, 2.4, 15.8 mg nicotine/g tobacco) among daily smokers from three vulnerable populations: individuals with affective disorders (n = 251), individuals with opioid use disorder (n = 256), and socioeconomically-disadvantaged women of reproductive age (n = 246). Effect of study cigarette assignment on urine toxicology screens (performed weekly) and responses to drug and alcohol use questionnaires (completed at study weeks 6 and 12) were examined using negative binomial regression, logistic regression, or repeated measures analysis of variance, controlling for sex, age, and menthol status. The most common substances identified using urine toxicology included tetrahydrocannabinol (THC; 44.8%), cocaine (9.2%), benzodiazepine (8.6%), and amphetamines (8.0%), with 57.2% of participants testing positive at least once for substance use (27.3% if excluding THC). No significant main effects of nicotine dose were found on any of the examined outcomes. These results suggest that reducing nicotine content does not systematically increase use of other substances, even among individuals at increased risk of substance use. ClinicalTrials.gov Identifiers: NCT02232737, NCT2250664, NCT2250534.

Leveraging the cigarette purchase task to understand relationships between cumulative vulnerabilities, the relative reinforcing effects of smoking, and response to reduced nicotine content cigarettes

We examined if the relative-reinforcing effects of smoking increase with greater cumulative vulnerability and whether cumulative vulnerability moderates response to reduced nicotine content cigarettes. Participants were 775 adults from randomized clinical trials evaluating research cigarettes differing in nicotine content (0.4, 2.4, 15.8 mg/g). Participants were categorized as having low (0-1), moderate (2-3), or high (≥4) cumulative vulnerability. Vulnerabilities included rural residence, opioid use disorder, affective disorder, low educational attainment, poverty, unemployment, and physical disability. We used the cigarette purchase task (CPT) to assess the relative-reinforcing effects of participants' usual-brand cigarettes at baseline and study cigarettes during the 12-week trial. The CPT is a behavioral-economic task wherein participants estimate likely smoking (demand) over 24 h under escalating cigarette price. Demand is characterized by two factors: Amplitude (demand volume at zero/minimal price) and Persistence (demand sensitivity to price). Greater cumulative vulnerability was associated with greater demand Amplitude (F[2709] = 16.04,p < .0001) and Persistence (F[2709] = 8.35,p = .0003) for usual-brand cigarettes. Demand Amplitude for study cigarettes increased with increasing cumulative vulnerability (F[2619] = 19.59, p < .001) and decreased with decreasing nicotine content ([4879] = 5.45, p < .001). The only evidence of moderation was on demand Persistence (F[8867] = 2.00,p = .04), with larger reductions at the 0.4 mg/g compared to 15.8 mg/g doses among participants with low compared to moderate or high cumulative vulnerability. The relative-reinforcing effects of smoking clearly increase with greater cumulative vulnerability. Reducing nicotine content would likely reduce demand Amplitude across cumulative-vulnerability levels but reductions in demand Persistence may be more limited among those with greater cumulative vulnerability.

Effects of very low nicotine content cigarettes on smoking across vulnerable populations

There has been long-standing interest in a reduced-nicotine product standard for combusted tobacco, which is within the regulatory purview of the Food and Drug Administration (FDA). In weighing whether to establish this standard, it is important to consider potential responses among people who are at elevated risk for tobacco-related health harms. In this narrative review, we summarize studies of very low nicotine content (VLNC) cigarettes conducted between 2010 and 2021 in groups that the FDA has identified as vulnerable populations. Studies conducted to date in adults with mental health conditions, adults with opioid use disorder, socioeconomically-disadvantaged adults, and youth or young adults indicate that immediate switching to VLNC cigarettes decreases smoking, with minimal or no unintended negative consequences. Few studies have investigated the effects of VLNC cigarettes in racial or ethnic minorities, people who smoke menthol cigarettes, and pregnant women, but initial findings suggest that responses of these individuals are similar to responses observed in other vulnerable populations. We are not aware of studies that have investigated VLNC cigarettes in military/veteran populations, sexual or gender minority individuals, or people living in underserved rural environments. Future research directions include understanding how to promote cessation in the context of a reduced-nicotine standard, and how to correct VLNC misperceptions in vulnerable populations. Nevertheless, the evidence to date indicates that a reduced-nicotine standard is likely to have the same beneficial effects on smoking reductions as it does in less vulnerable populations, which should provide some confidence in pursuing this regulatory approach.

Using crowdsourcing to study the differential effects of cross-drug withdrawal for cigarettes and opioids in a behavioral economic demand framework

Smoking rates among those who use prescribed or recreational opioids are significantly higher than the general population. Hypothesized neuropharmacological interactions between opioids and nicotine may contribute to this pattern of polysubstance use, especially during withdrawal. However, little research has examined how the withdrawal of one substance may affect the consumption of the other (i.e., cross-drug withdrawal effects). Behavioral economic demand tasks (e.g., hypothetical purchase tasks) can be used to quickly assess the value of a drug. Crowdsourcing can be a convenient tool to gain preliminary insight into different processes in substance valuation that may otherwise be impossible or prohibitively difficult to study. The purpose of the present study was to provide a preliminary examination of the effects of hypothetical withdrawal of cigarettes and opioids on the consumption of those drugs among polysubstance users. Amazon Mechanical Turk workers who reported daily smoking and at least monthly opioid use completed a series of hypothetical purchase tasks for doses of opioids and cigarettes under various withdrawal conditions. Sensitivity to the price of both drugs decreased when under withdrawal for either, indicating a higher drug value of cigarettes and opioids due to effects of cross-drug withdrawal. Nicotine and opioid dependence severity, impulsive choice, and riskiness were also positively related to drug purchasing. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Validity of a little cigars/cigarillos purchase task in dual users of cigars and cigarettes

INTRODUCTION

Hypothetical purchase tasks have been widely used to assess the reinforcing value of tobacco products. However, a task has not yet been validated for little cigars and cigarillos (LCCs), a popular tobacco product class among vulnerable populations. This study sought to validate the LCC Purchase Task (LCCPT) in a sample of experienced LCC smokers.

METHODS

Data were collected from 65 young adult (18-34 years) LCC and cigarette dual users (78.5% male) in Connecticut (2018-2020). Participants completed the usual-brand LCCPT for consumption in 24 h at increasing prices. We calculated four observed demand indices: intensity (consumption at $0), breakpoint (price after which consumption reaches 0), Omax (maximum daily expenditure), and Pmax (price at which daily expenditure was maximized). Two indices were estimated from demand curves: Q0 (predicted consumption as price approaches $0) and price-sensitivity (sensitivity to price increases). Spearman correlations and multivariable regressions examined the associations between demand indices, self-reported cigar use, and dependence.

RESULTS

Correlations were in expected directions. All indices except breakpoint and Pmax were positively correlated with use, and all indices were correlated with multiple measures of dependence. Overall, greater demand and expenditure for LCCs and lower sensitivity to price changes were correlated with greater use and dependence. In regression analyses intensity and price-sensitivity showed the strongest relationships with use and dependence.

CONCLUSIONS

The validity of the LCCPT was supported in a sample of experienced LCC smokers. This instrument can be incorporated into other protocols to assess the abuse liability of LCCs.

Blood Nicotine Predicts the Behavioral Economic Abuse Liability of Reduced-Nicotine Cigarettes

BACKGROUND

Cigarette smoking continues to be a major health concern and remains the leading preventable cause of death in the US. Recent efforts have been made to determine the potential health and policy benefits of reducing nicotine in combustible cigarettes. The degree to which changes in blood nicotine relate to measures of the abuse liability of reduced-nicotine cigarettes is unknown. The current study examined the relation between blood nicotine and behavioral economic demand measures of cigarettes differing in nicotine content.

METHODS

Using a within-subject design, participants smoked a single cigarette during each experimental session. Cigarettes included the participant's usual-brand cigarette and SPECTRUM investigational cigarette differing in nicotine level (mg of nicotine to g of tobacco; 15.8 mg/g, 5.2 mg/g, 2.4 mg/g, 1.3 mg/g, and 0.4 mg/g). During each session, blood was collected at multiple timepoints and behavioral economic demand was assessed. Nonlinear mixed-effects models were used to estimate differences in derived intensity (Q0) and change in elasticity (α).

RESULTS

Measures of blood nicotine decreased in an orderly fashion related to nicotine level and significantly predicted change in elasticity (α), but not derived intensity. No differences in demand parameters between the usual brand and 15.8mg/g cigarettes were observed. However, α was significantly higher (lower valuation) for 0.4mg/g than 15.8mg/g cigarettes.

CONCLUSIONS

The lowest nicotine level (0.4mg/g) corresponded with the lowest abuse liability (α) compared to the full-strength control (15.8mg/g), with the 1.3mg/g level also resulting in low abuse liability.

IMPLICATIONS

This is the first study examining the relative contributions of nicotine content in cigarettes and blood nicotine levels on the behavioral economic demand abuse liability of cigarettes ranging in nicotine content. Our results suggest blood nicotine and nicotine content both predict behavioral economic demand abuse liability. In addition, our results suggest a nicotine content of 1.3mg/g or lower may be effective at reducing cigarette uptake among first-time (naïve) smokers. Our results largely conform to previous findings suggesting a very low nicotine content cigarette maintains lower abuse liability than full-strength cigarettes.

Effects of Reduced Nicotine Content Cigarettes on Fractional Exhaled Nitric Oxide and Self-Reported Respiratory Health Outcomes Among Smokers With Psychiatric Conditions or Socioeconomic Disadvantage

INTRODUCTION

This study examined whether exposure to reduced-nicotine-content cigarettes (RNCCs) for 12 weeks alters respiratory health using Fractional Exhaled Nitric Oxide (FeNO), a validated biomarker of respiratory epithelial health, and the Respiratory Health Questionnaire (RHQ), a subject-rated questionnaire on respiratory symptoms. Participants were 747 adult daily smokers enrolled in three double-blind, randomized clinical trials evaluating effects of cigarette nicotine content (0.4, 2.4, 15.8 mg nicotine/g tobacco) in people with affective disorders, opioid use disorder (OUD), or socioeconomic disadvantage.

AIMS AND METHODS

FeNO levels and RHQ ratings were collected at baseline and Weeks 6 and 12 following randomization. Multiple regression was used to assess associations of FeNO and RHQ with smoking characteristics. Mixed-model repeated-measures ANOVA was used to evaluate the effects of nicotine content on FeNO and RHQ outcomes over the 12-week study period.

RESULTS

FeNO levels but not RHQ ratings varied inversely with smoking characteristics at baseline (Ps < 0.0001) in smokers with affective disorders and socioeconomic disadvantage but less so in those with OUD. Participants with affective disorders and socioeconomic disadvantage, but not those with OUD, who were assigned to RNCCs had higher FeNO levels at Week 12 than those assigned to the 15.8 mg/g dose [F(2,423) = 4.51, p = .01, Cohen's d = 0.21]. No significant dose-related changes in RHQ scores were identified.

CONCLUSIONS

Use of RNCCs across a 12-week period attenuates smoking-related reductions in FeNO levels in smokers with affective disorders and socioeconomic disadvantage although not those with OUD. FeNO changes were not accompanied by changes in respiratory-health ratings.

TRIAL REGISTRATION

Inclusion and exclusion criteria for the sample and experimental manipulation of the nicotine content of assigned cigarettes are registered: NCT02232737, NCT02250664, NCT02250534. The FeNO measure reported in this manuscript is an exploratory outcome that was not registered.

IMPLICATIONS

Should a reduced nicotine content standard be implemented; these results suggest that reduced nicotine content in cigarettes will not exacerbate and instead may attenuate smoking-related decreases in FeNO. This is significant as NO is an important component in maintaining a healthy respiratory system and necessary to defend against infection. Furthermore, the results of the current study demonstrate that the adoption of the reduced nicotine content standard may result in beneficial impacts on respiratory epithelial health among vulnerable populations that are disproportionally affected by the adverse health outcomes precipitated by combustible tobacco use.

Calibrated dynamic borrowing using capping priors

Multisource exchangeability models (MEMs), a BayeTsian approach for dynamically integrating information from multiple clinical trials, are a promising approach for gaining efficiency in randomized controlled trials. When the supplementary trials are considerably larger than the primary trial, care must be taken when integrating supplementary data to avoid overwhelming the primary trial. In this paper, we propose "capping priors," which controls the extent of dynamic borrowing by placing an a priori cap on the effective supplemental sample size. We demonstrate the behavior of this technique via simulation, and apply our method to four randomized trials of very low nicotine content cigarettes.

Estimation of the dose of electronic cigarette chemicals deposited in human airways through passive vaping

BACKGROUND

Existing studies on the health effects of e-cigarettes focused on e-cigarette users themselves. To study the corresponding effects on passive vapers, it is crucial to quantify e-cigarette chemicals deposited in their airways.

OBJECTIVE

This study proposed an innovative approach to estimate the deposited dose of e-cigarette chemicals in the passive vapers' airways. The effect of the distance between active and passive vapers on the deposited dose was also examined.

METHODS

The chemical constituent analysis was conducted to detect Nicotine and flavoring agents in e-cigarette aerosol. The Mobile Aerosol Lung Deposition Apparatus (MALDA) was employed to conduct aerosol respiratory deposition experiments in real-life settings to generate real-time data.

RESULTS

For e-cigarette aerosol in the ultrafine particle regime, the deposited doses in the alveolar region were on average 3.2 times higher than those in the head-to-TB airways, and the deposited dose in the passive vaper's airways increased when being closer to the active vaper.

SIGNIFICANCE

With prolonged exposure and close proximity to active vapers, passive vapers may be at risk for potential health effects of harmful e-cigarette chemicals. The methodology developed in this study has laid the groundwork for future research on exposure assessment and health risk analysis for passive vaping.

Cumulative vulnerabilities as a potential moderator of response to reduced nicotine content cigarettes

Risk for smoking increases in a summative manner corresponding to the number of co-occurring vulnerabilities present (cumulative vulnerability). We examined whether cumulative vulnerabilities moderate response to reduced nicotine content cigarettes in a secondary analysis of results from 775 participants in three 12-week randomized clinical trials examining research cigarettes varying in nicotine content (0.4, 2.4, 15.8 mg nicotine/g tobacco). Participants were categorized as having 0-1, 2-3, or ≥ 4 cumulative vulnerabilities. Vulnerabilities included: rural residence, current substance use disorder, current affective disorder, low educational attainment, poverty, unemployment, physical disability. The primary outcome was total cigarettes per day (CPD) during Week 12; secondary outcomes included CPD across weeks, toxin exposure, dependence severity, craving/withdrawal (17 dependent measures). Results were analyzed using repeated measures analysis of covariance and growth-curve modeling. Total CPD during Week 12 increased as cumulative-vulnerability increased (P = 0.004), and decreased as nicotine content decreased (P < 0.001), with no significant interaction of cumulative vulnerability and dose (P = 0.67). Effects on other outcomes generally followed that same pattern. The only exception across the other outcomes was on Questionnaire-on-Smoking-Urges Factor-2 ratings for usual-brand cigarettes where cumulative vulnerability, dose, and time interacted (P = 0.007), with craving at the 0.4 and 2.4 mg/g doses decreasing over time, but inconsistently across vulnerability categories. Overall, we saw little evidence that cumulative vulnerabilities moderate response to reduced nicotine content cigarettes suggesting that a policy reducing nicotine content in cigarettes to minimally addictive levels could benefit even highly vulnerable smokers including those residing in rural or other regions with overrepresentation of co-occurring vulnerabilities. Clinicaltrials.gov identifiers: NCT02232737, NCT02250664, NCT02250534.

Reactions to reduced nicotine content cigarettes in a sample of young adult, low-frequency smokers

RATIONALE

Reducing nicotine content in cigarettes to ≤ 2.4 mg per g of tobacco [mg/g] reduces smoking behavior and toxicant exposure among adult daily smokers. However, cigarettes with similar nicotine content could support continued experimentation and smoking progression among young adults who smoke infrequently.

OBJECTIVES

This study evaluated the threshold for nicotine in cigarettes that produces reactions associated with smoking progression in a sample of young adults who smoke infrequently.

METHODS

Young adults (n = 87, 18-25 years, 49% female) using tobacco products ≤ 15 days per month completed three counterbalanced, double-blinded sessions, each measuring positive and negative subjective reactions to fixed doses of smoke from investigational cigarettes containing one of three different nicotine contents: normal (NNC; 15.8 mg/g); very low (VLNC; 0.4 mg/g); and intermediate (INC; 2.4 mg/g). In a final session, participants chose one of the cigarettes to self-administer.

RESULTS

Post-cigarette breath carbon monoxide was greater for VLNC than for NNC (p < 0.001). Positive reactions were greater for NNC than INC (p < 0.001) and for INC than VLNC (p = 0.001). Negative reactions were greater for NNC than INC and VLNC (both p < 0.001); INC and VLNC did not differ. Cigarette choices did not differ from an even distribution (43% NNC, 25% INC, 32% VLNC), but choice for NNC or INC was associated with higher ratio of positive to negative reactions during the NNC and INC fixed dose sessions, respectively (p < 0.001).

CONCLUSIONS

Reducing nicotine content will likely lower the abuse liability of cigarettes for most young, low-frequency smokers. Additional work is needed to determine if compensatory smoking may lead to increased toxicant exposure, and if a subset of individuals choosing lower nicotine cigarettes may continue to smoke regardless of nicotine content.

Signaling pathway perturbation analysis for assessment of biological impact of cigarette smoke on lung cells

Exposure to cigarette smoke (CS) results in injury to the epithelial cells of the human respiratory tract and has been implicated as a causative factor in the development of chronic obstructive pulmonary disease and lung cancers. The application of omics-scale methodologies has improved the capacity to understand cellular signaling processes underlying response to CS exposure. We report here the development of an algorithm based on quantitative assessment of transcriptomic profiles and signaling pathway perturbation analysis (SPPA) of human bronchial epithelial cells (HBEC) exposed to the toxic components present in CS. HBEC were exposed to CS of different compositions and for different durations using an ISO3308 smoking regime and the impact of exposure was monitored in 2263 signaling pathways in the cell to generate a total effect score that reflects the quantitative degree of impact of external stimuli on the cells. These findings support the conclusion that the SPPA algorithm provides an objective, systematic, sensitive means to evaluate the biological impact of exposures to CS of different compositions making a powerful comparative tool for commercial product evaluation and potentially for other known or potentially toxic environmental smoke substances.

Impact of nicotine reduction in cigarettes on smoking behavior and exposure: Are there differences by race/ethnicity, educational attainment, or gender?

BACKGROUND

Lowering nicotine in cigarettes may reduce smoking prevalences; however, it is not known whether an immediate or gradual reduction in nicotine is the optimal approach for all population groups.

OBJECTIVES

We examined whether the optimal approach to nicotine reduction depended on the education, gender, or race of people who smoke and whether the optimal approach differentially benefited people who smoke based on their education, gender, or race.

METHODS

Secondary analysis was conducted on a randomized clinical trial (N = 1250) comparing (1) immediate reduction from 15.5 to 0.4 mg of nicotine per gram of tobacco(mg/g);(2) gradual reduction to 0.4 mg/g;(3) control group with normal nicotine cigarettes(15.5 mg/g). Outcomes included cigarettes per day(CPD), carbon monoxide(CO), total nicotine equivalents(TNE), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides(NNAL), phenanthrene tetraol(PheT), N-Acetyl-S-(2-cyanoethyl)-l-cysteine(CEMA). Data were analyzed as area under the curve(AUC).

RESULTS

Results were presented by education (High school[HS] or less n = 505, more than HS n = 745), gender (males n = 701, females n = 549), and race (Black participants n = 373,White participants n = 758). Regardless of education, gender, and race, CPD, CO, TNE, NNAL, PheT, and CEMA were lower in immediate versus gradual nicotine reduction. Comparing immediate versus the control, outcomes were lower for all subgroups; however, the magnitude of the effect for TNE varied by race. Specifically, geometric mean of the AUC of TNE in immediate versus gradual was 49 % lower in Black participants and 61 % lower in White participants (p-value = 0.047).

CONCLUSIONS

Immediately reducing nicotine in cigarettes has the potential to benefit people who smoke across lower and higher educational attainment, male and female gender, and Black and White race.

Regulatory approaches and implementation of minimally addictive combusted products

INTRODUCTION

A joint meeting was held by the World Health Organization (WHO) and the Convention Secretariat of the WHO Framework Convention on Tobacco Control to examine the potential effects of a regulatory policy to reduce nicotine in cigarettes to minimally addictive levels. This paper reviews the feasibility of and approaches to implementing a nicotine product standard.

METHODS

Prior WHO reports on this topic were consulted and a systematic review of the scientific literature was conducted. The paper was reviewed by the participants at the aforementioned meeting and their feedback was incorporated.

RESULTS

The nicotine dose most likely to consistently reduce smoking behavior and dependence is < 0.4 mg nicotine/g tobacco. An immediate rather than a gradual nicotine reduction approach appears to be more beneficial. Smokers are likely to seek nicotine from alternate sources (e.g., nicotine replacement therapies, e-cigarettes) or potentially, the illegal market. As such, the availability of alternative products, as well as strong policies against illegal markets, can potentially mitigate unintended consequences. An effective reduced nicotine regulation must be imbedded in a comprehensive and strong tobacco control program that includes public education and surveillance. Barriers and challenges to implementing a nicotine product standard exist, particularly in low-capacity countries.

CONCLUSION

Not all countries will have the capacity to implement a regulation to reduce nicotine in cigarettes (and preferably other combusted tobacco products) to minimally addictive levels. However, for the countries that choose to implement it, such a policy could potentially dramatically reduce the burden of tobacco use.

Effects of Reduced-Nicotine Cigarettes Across Regulatory Environments in the Experimental Tobacco Marketplace: A Randomized Trial

INTRODUCTION

Cigarette smoking remains the leading preventable cause of death in the United States. Recent efforts have explored the potential health and policy benefits of reducing nicotine, an addictive component, in combustible cigarettes. To date, an experimental, prospective analysis directly comparing the effects of varying regulatory environments on purchases of multiple products has yet to be conducted. The present study compared real purchasing of conventional cigarettes, reduced-nicotine cigarettes, and a variety of other nicotine and tobacco products across a range of regulatory environments.

METHODS

Participants were assigned to one of five groups, each associated with a different nicotine level (mg of nicotine to g of tobacco) in SPECTRUM investigational cigarettes (15.8, 5.2, 2.4, 1.3, and 0.4 mg/g). Across sessions, participants made real purchases for nicotine/tobacco products in an Experimental Tobacco Marketplace. Each session corresponded with a distinct regulatory environment wherein different nicotine/tobacco products were available for purchase.

RESULTS

Our results suggest that the primary drivers of cigarette and nicotine purchasing are regulatory environment and the presence/absence of alternative nicotine and tobacco products. Perhaps surprisingly, nicotine level does not appear to be such a driver of purchasing behavior under these experimental conditions. Investigational cigarette purchasing is lowest when other preferred combustible products are available and highest when investigational cigarettes are the only combustible product available for purchase.

CONCLUSIONS

If a reduced-nicotine policy is implemented, great care should be taken in determining and making available less-harmful nicotine/tobacco products as the availability of preferred combustible products may result in undesirable levels of purchasing.

IMPLICATIONS

This is the first experimental study investigating different potential regulatory effects related to a reduced-nicotine policy by examining purchasing across a range of nicotine/tobacco products. Our results suggest the presence of affordable, highly preferred combustible products is likely to maintain tobacco purchasing at undesirable levels. To promote switching to less-harmful products, affordable alternate nicotine and tobacco products should be readily available. Finally, our results suggest that the availability of noncigarette products, not cigarette nicotine level, will most likely affect purchasing of reduced-nicotine cigarettes.

Acute subjective sensory perceptions predict relative reinforcing effects of smoked nicotine

INTRODUCTION

Smoking is believed partially reinforcing via immediate sensory perceptions. Yet, unknown is whether a cigarette's relative reinforcing efficacy can be predicted by these perceptions and whether this relationship may vary due to constituents known to alter those perceptions.

METHODS

Sensory perceptions of acute smoking were examined as predictors of subsequent cigarette choice behavior. Also tested was whether nicotine content or menthol affected this relationship. Adult dependent smokers (N = 37) participated in five sessions comparing cigarettes varying in nicotine contents (NIC; 1.3, 2.3, 5.5, 11.2, and 17.4 mg/g), relative to the very lowest nicotine content, 0.4 mg/g (VLNC). Non-menthol (n = 17) and menthol (n = 20) cigarettes-matched on nicotine-were provided based on participant preference. One NIC was compared versus VLNC per session (single-blinded); NIC content order was randomized across sessions on separate days. Perceptions (e.g., "liking", "satisfying") were measured immediately after initial sampling of NIC or VLNC, followed by a validated puff-by-puff choice procedure to determine preference for each NIC versus VLNC.

RESULTS

NIC perceptions (difference from VLNC) and puff choices increased with nicotine. Menthol moderated associations between perceptions and nicotine; and between puff choices and nicotine. Perceptions were predictive of puff choice-greater magnitude of difference in perceptions between VLNC and NIC led to more NIC puff choices. When testing perceptions' prediction of puff choices, neither the main effect of menthol or interaction of Perceptions X Nicotine Condition were significant.

CONCLUSIONS

Consistent with assumed-but rarely tested-causes of smoking reinforcement, sensory perceptions from a cigarette predict its relative reinforcing efficacy.

Appeal, subjective effects, and relative reinforcing effects of JUUL that vary in flavor and nicotine content

The U.S. Food and Drug Administration has the authority to regulate characteristics of electronic nicotine delivery systems (ENDS). Prior research indicates that regulation of certain characteristics of these products may have an effect on their appeal and use. Policies that affect appeal and use of ENDS are relevant to attempts to reduce use among young people-including young adults-but are also relevant to adults who use these products as harm reduction tools. Using a novel concurrent choice task, we evaluated the relative reinforcement of JUUL brand ENDS products that varied in flavor (n = 8) and nicotine (n = 8) among samples of young adults who use JUUL. Findings suggest that restricting JUUL flavor to tobacco-only results in decreased appeal, while reducing the nicotine content of JUUL pods to 3%-from the conventional 5%-does not have an effect on product appeal. Findings also validate a novel methodology for delivering fixed doses of ENDS vapor within the context of a task that assesses the relative reinforcement of ENDS products with varying characteristics. This methodology can be applied to assessing the relative reinforcing effects of a wide variety of tobacco products with varied characteristics. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Switching to Progressively Reduced Nicotine Content Cigarettes in Smokers With Low Socioeconomic Status: A Double-Blind Randomized Clinical Trial

INTRODUCTION

The Food and Drug Administration issued an advanced notice of proposed rulemaking for setting a product standard for nicotine levels in cigarettes, with an emphasis on minimally or non-addicting very low nicotine content (VLNC).

METHODS

A 33 week, two-arm, double-blind randomized trial conducted in Hershey, Pennsylvania, USA and Washington, DC, USA included adult daily cigarette smokers (≥5 cigarettes per day) with less than a college degree, and who had no plans to quit within the next six months. Participants were randomized to either reduced nicotine content (RNC) study cigarettes tapered every three weeks to a final VLNC (0.2 mg/cigarette) for six weeks or to usual nicotine content (UNC) study cigarettes (11.6 mg/cigarette). Outcomes included acceptability of study cigarettes measured by attrition (primary outcome), compliance, reduction in cigarette dependence and tobacco biomarkers, and post-intervention cessation.

RESULTS

The RNC (n = 122) versus UNC (n = 123) group had higher attrition (adjusted Hazard Ratio 3.4; 95% confidence interval [CI] 1.99 to 5.81). At the end of the intervention, cotinine levels were 50% lower in the RNC group (mean group difference -137 ng/mL; 95% CI -172, -102). The RNC group smoked fewer CPD (-4.1; 95% CI -6.44, -1.75) and had lower carbon monoxide levels (-4.0 ppm; 95% CI -7.7, -0.4). Forty seven percent (29/62) of the RNC group were biochemically-confirmed compliant with smoking VLNC cigarettes (mean cotinine = 8.9 ng/ml). At three month follow-up, only compliant VLNC smokers quit with an assisted quit attempt (N = 6/22, 27%).

CONCLUSIONS

This study supports a VLNC standard in cigarettes.

IMPLICATIONS

Differential dropout and noncompliance indicate some smokers had difficulty transitioning to cigarettes with reduced nicotine. These smokers will benefit from supplemental nicotine in medicinal or noncombustible tobacco products if a nicotine reduction standard is established. Other smokers successfully transitioned to very low nicotine content cigarettes exclusively and substantially reduced their exposure to nicotine.

Risk Perceptions of Low Nicotine Cigarettes and Alternative Nicotine Products across Priority Smoking Populations

BACKGROUND

As the U.S. Food and Drug Administration considers a low nicotine product standard for cigarettes, it is important to examine how people who smoke, especially individuals from priority populations disproportionately affected by smoking, perceive low nicotine content (LNC) cigarettes and their relative risk perceptions of alternative nicotine delivery system (ANDS) products, including e-cigarettes and snus, and medicinal nicotine.

METHODS

Data are from Wave 4 (2016-2017) of the adult Population Assessment of Tobacco Use and Health (PATH) Study. We examined respondents' absolute risk perceptions about nicotine, LNC cigarettes, ANDS products and medicinal nicotine; their relative risk perceptions of LNC cigarettes and ANDS products compared to conventional cigarettes; and their relative risk perceptions of medicinal nicotine compared to ANDS products.

RESULTS

The majority of respondents across priority smoking populations indicated snus, e-cigarettes, and LNC cigarettes were 'about the same' level of harmfulness or addictiveness as conventional cigarettes. The majority of respondents indicated e-cigarettes to be 'about the same' harmfulness as medicinal nicotine.

CONCLUSIONS

Our study indicates that adults who smoke cigarettes generally have misperceptions about the harms of nicotine and the relative risks of ANDS products and such misperceptions exist regardless of their racial/ethnic identity, sexual orientation, and gender identity.

A Forced-Choice Procedure to Assess the Acute Relative Reinforcing Effects of Nicotine Dose per se in Humans

INTRODUCTION

A method to assess acute reinforcement due to nicotine may aid identification of doses needed to maintain dependence. After describing development of a forced-choice procedure, results are presented from two studies using it to determine the relative reinforcing effects of nicotine dose per se.

AIMS AND METHODS

Choice between a higher versus a very low or no nicotine option, via smoking (Study 1, n = 59) and via nasal spray (Study 2, n = 42), was assessed in nontreatment-seeking dependent smokers abstinent overnight. Using a within-subject design, different nicotine levels for each product were administered under blind conditions, initially to assess their discriminability (Study 1: 1.3-17 mg/g each vs. 0.4 mg/g nicotine Spectrum cigarettes; Study 2: 2.5 µg/kg vs. 0 µg/kg nicotine per spray). At the end of sessions for each study, participants engaged in forced-choice trials to assess preference, requiring a fixed number of puffs/sprays for one and/or the other.

RESULTS

Confirming the procedure's validity, the choice of the higher nicotine option was significantly greater than that for the very low or no nicotine option in both studies. In Study 1, choice relative to 0.4 mg/g was greater for cigarettes 5.3 mg/g or more but not 2.3 mg/g or less (p = .003 for the interaction of higher content vs. 0.4 mg/g comparison). In Study 2, choice was greater for the nicotine versus placebo spray (p < .005), as nicotine was preferred nearly twice as much as the placebo.

CONCLUSION

This forced-choice procedure may efficiently determine the relative reinforcing value of a nicotine dose per se.

IMPLICATIONS

The forced-choice procedure described here may identify nicotine doses that are acutely reinforcing in dependent smokers. A priori research of choice comparisons between small versus zero nicotine doses could inform clinical research in larger and more diverse samples to determine nicotine contents in cigarettes, and perhaps in other commercial products, that are not reinforcing and, thus, likely to reduce the risk of their addictiveness. This procedure may also be applicable to assessing changes in acute nicotine reinforcement due to different product formulations, novel drugs, or other manipulations, perhaps helping inform development of new interventions for cessation or harm reduction.

Relationship between Comorbid Drug Use Disorders, Affective Disorders, and Current Smoking

This study aimed to identify subgroups of adults based on comorbid psychiatric disorders and to examine the relationship with current smoking. Method: The National Epidemiologic Survey on Alcohol and Related Conditions-III, 2012-2013, sampled, recruited, and assessed 36,309 adults, with interviews on drug use and other characteristics. The Alcohol Use Disorder and Associated Disabilities Interview Schedule DSM-5 Version (AUDADIS-5) was used to identify psychiatric conditions. Latent class models were developed based on various psychiatric diagnoses. Multinomial logistic regression estimated the significance of covariates in predicting class membership. Results: Four latent classes optimally distinguished the population: no comorbid conditions (63%), comorbid affective disorders (16%), those with alcohol use disorder (AUD; 17%), and a highly comorbid subgroup (i.e., co-occurring affective and drug use disorders; 4%). Current smoking was about twice as prevalent in the classes defined by psychiatric conditions compared to the group with no comorbid conditions. The highly comorbid class was more likely to be current smokers than the comorbid affective disorders class and the AUD class. Furthermore, the highly comorbid class was younger and had lower income, and the AUD class had a higher proportion of males than the other classes. Conclusions: Cigarette smoking was higher in the nearly 40% of respondents characterized by psychiatric disorders, particularly those with drug use disorders. Correlates of membership in these classes were consistent with known vulnerabilities for smoking, highlighting the need for mental health interventions and future research to explicitly address tobacco cessation in clinical settings based on psychiatric diagnoses.

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).

Using the Cigarette Purchase Task to examine the relative reinforcing value of cigarettes among mothers with versus without opioid dependence

The Cigarette Purchase Task (CPT), in which participants estimate the number of cigarettes they would smoke across increasing cigarette prices, measures the relative reinforcing value of cigarettes. Although opioid-dependent individuals are particularly vulnerable to tobacco addiction, more research is needed to elucidate whether and to what extent their motivation to smoke differs from not-opioid-dependent smokers controlling for potential sociodemographic differences. Participants were 173 women (65 opioid-dependent) in an ongoing clinical trial for smoking cessation. Baseline CPT responses were compared between opioid-dependent and not-opioid-dependent women using five demand indices: Demand Intensity; O_max; P_max; Breakpoint (BP); and α, and two latent factors: Amplitude and Persistence. Final regression models adjusted for sociodemographic characteristics differing between the two groups. Opioid-dependent women had greater demand Intensity (i.e., number of cigarettes they would smoke if they were free) than not-opioid dependent women in the adjusted model, F(1, 156) = 6.93, p = .016. No other demand indices differed significantly. Regarding latent factors, demand Amplitude (i.e., volumetric consumption), but not Persistence (i.e., price insensitivity), was greater for opioid-dependent women in the adjusted model, F(1, 146) = 4.04, p = .046. These results further demonstrate that the CPT is a highly sensitive task that can illuminate potentially important individual and population differences in the relative reinforcing value of smoking. Greater demand Intensity and Amplitude differentiated smokers with comorbid opioid dependence; thus, decreasing smoking prevalence among opioid-dependent populations may require policies and interventions that can decrease cigarette demand Intensity and Amplitude. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Investigating tobacco withdrawal in response to reduced nicotine cigarettes among smokers with opioid use disorder and other vulnerabilities

Individuals with opioid use disorder (OUD) have high prevalence of smoking and poor cessation outcomes. Data suggest that smokers with OUD may experience heightened nicotine reinforcement and more severe tobacco withdrawal compared to smokers without OUD. The Food and Drug Administration is currently considering reducing the nicotine content of cigarettes to reduce smoking prevalence and smoking-related disease. It is critical to understand the effects of reduced nicotine content cigarettes (RNCCs) on tobacco withdrawal in this subgroup. In this secondary analysis, we investigated the ability of RNCCs to attenuate acute tobacco withdrawal and craving severity in smokers with OUD versus those without substance use disorders (SUDs). Smokers maintained on methadone or buprenorphine (opioid-maintained [OM]; n = 65) versus without other SUDs (i.e., non-SUD; n = 135) completed 5 laboratory sessions wherein they smoked their usual brand (UB) or a research cigarette varying in nicotine content (0.4, 2.4, 5.2, 15.8 mg/g of tobacco) under double-blind, acute abstinence conditions. Participants completed the Minnesota Tobacco Withdrawal Scale, including a desire to smoke (craving) item, before and every 15 min for 1 hr following smoking each cigarette. Tobacco withdrawal and craving did not differ significantly by OM status in response to UB or RNCCs. In addition to the Dose × Time interaction, greater depression and cigarette dependence consistently predicted withdrawal and craving (ps < .05). Across all cigarettes, tobacco withdrawal and craving did not significantly differ by OM status, suggesting that smokers receiving opioid agonist treatment may respond favorably to RNCCs. Additional studies with larger and more diverse samples are needed to address this question more definitively. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Reinforcer pathology II: Reward magnitude, reward delay, and demand for alcohol collectively relate to college students' alcohol related problems

The reinforcer pathologies model of addiction posits that two characteristic patterns of operant behavior characterize addiction. Specifically, individuals suffering from addiction have elevated levels of behavioral economic demand for their substances of abuse and have an elevated tendency to devalue delayed rewards (reflected in high delay discounting rates). Prior research has demonstrated that these behavioral economic markers are significant predictors of many of college students' alcohol-related problems. Delay discounting, however, is a complex behavioral performance likely undergirded by multiple behavioral processes. Emerging analytical approaches have isolated the role of participants' sensitivity to changes in reinforcer magnitude and changes in reinforcer delay. The current study uses these analytic approaches to compare participants' discounting of money versus alcohol, and to build regression models that leverage these new insights to predict a wider range of college students' alcohol related problems. Using these techniques, we were able to 1) demonstrate that individuals differed in their sensitivity to magnitudes of alcohol versus money, but not sensitivity to delays to those commodities and 2) that we could use our behavioral economic measures to predict a range of students' alcohol related problems.

Abuse liability of cigarettes with very low nicotine content in pregnant cigarette smokers

The U.S. Food and Drug Administration has proposed reducing the nicotine content of cigarettes to a minimally-addictive level. To our knowledge, this study is the first to examine how pregnant smokers respond to very low nicotine content (VLNC) cigarettes. In Phase 1, participants blindly sampled two VLNC cigarettes (0.4 and 2.4 mg/g of tobacco) and their usual brand (UB) cigarette in separate sessions, then completed a behavioral economic simulation task and measures of subjective effects, craving/withdrawal, and smoking topography. Phase 2 directly compared the relative reinforcing effects of the cigarettes using concurrent choice testing. All possible dose-pair combinations were tested in separate sessions where puffs were earned ad libitum by clicking the code associated with their preferred cigarette 10 times. Phase 3 tested the 0.4 mg/g-UB dose-pair where UB puffs could be earned with a progressively incremented number of clicks (maximum 8400). Ten pregnant smokers in Burlington, VT and Baltimore, MD participated in 2017-2018. Regarding abuse liability, participants chose the 0.4-mg/g dose less than UB (22% vs. 78%) during concurrent choice testing and the 0.4-mg/g dose sustained less demand than the 2.4-mg/g and UB doses on the simulation task. Positive subjective effects were also lower for both VLNC cigarettes vs. UB. Each cigarette reduced nicotine craving/withdrawal and no significant changes indicative of compensatory smoking were noted. Reducing the nicotine content of cigarettes may decrease their abuse liability in pregnant smokers without causing untoward craving/withdrawal or compensatory smoking. Studies of extended exposure to VLNCs in pregnant women are warranted.

Behavior change, health, and health disparities 2020: Some current challenges in tobacco control and regulatory science

This Special Issue of Preventive Medicine (PM) is the 7th in a series on behavior change, health, and health disparities. This series focuses on personal behavior patterns, including substance use disorders, physical inactivity/obesity, and non-adherence with medical regimens, which are among the most important modifiable causes of chronic disease and premature death. This 7th issue includes 17 commentaries, reviews, and original empirical studies, 16 of which are devoted to current tobacco control and regulatory science research and policy, topics critically important to protecting the public health from the longstanding and devastating harms of tobacco use. The challenge of balancing efforts to protect youth from e-cigarettes while allowing for evidence-based evaluation of their potential to reduce the harms of cigarette smoking among adults features prominently in many of these contributions, complemented by original studies on rural-urban disparities, tobacco harm perceptions, use patterns and toxin exposure, modeling of tobacco-related mortality, novel tobacco research methods, and reducing cigarette smoking through regulatory policies, including nicotine reduction in cigarettes, and novel clinical interventions. Continuing to give space in this series to the U.S. opioid epidemic, we also include an original empirical report on longitudinal trends of non-medical use of opioids from 2008 to 2020 in rural Appalachia, an epicenter in this epidemic. Across each of these topics we have recruited contributions from well-regarded investigators, clinicians, and policymakers to acquaint readers with recent advances and accomplishments while also noting knowledge gaps and unresolved challenges.

Relating individual differences in nicotine dependence severity to underpinning motivational and pharmacological processes among smokers from vulnerable populations

We examined whether elucidating underpinning smoking motivation and related pharmacological processes enhances understanding of nicotine dependence among smokers from vulnerable populations. Data were obtained between Oct, 2016 and Sept, 2019 from 745 adult smokers with co-morbid psychiatric conditions or socioeconomic disadvantage at University of Vermont, Brown University, Johns Hopkins University. Smoking motivation was assessed using the Cigarette Purchase Task (CPT), a behavioral-economic task that models the relative reinforcing value of smoking under varying monetary constraint. Dependence severity was measured using the Heaviness of Smoking Index (HSI), Fagerström Test for Nicotine Dependence total scores (FTND), and FTND total scores minus items 1 and 4 (FTND_2,3,5,6). We also assessed associations between dependence severity and smoking motivation with nicotine levels and metabolism rate. Principal Component Analysis was used to examine the latent structure of the conventional five CPT indices; bivariate and multivariable modeling was used to test associations. Factor analysis resulted in a two-factor solution, Amplitude (demand unconstrained by price) and Persistence (price sensitivity). CPT latent factors were associated with each dependence-severity measure (ps ≤ 0.0001), with associations stronger for Amplitude than Persistence across each, especially HSI which was exclusively associated with Amplitude_. Amplitude and each dependence measure were associated with nicotine intake (ps ≤ 0.0002); Persistence was not (p = .19). Demand Amplitude more than Persistence appears key to understanding individual differences in dependence severity. Regarding potential application, the results suggest a need for interventions that more effectively target demand Amplitude to make greater headway in reducing smoking in vulnerable populations. Trial Registration:clinicaltrials.gov identifiers: NCT02232737, NCT02250664, NCT02250534.

Tobacco harm reduction: Past history, current controversies and a proposed approach for the future

Tobacco harm reduction remains a controversial topic in tobacco control. Tobacco harm reduction involves providing tobacco users who are unwilling or unable to quit using nicotine products with less harmful nicotine-containing products for continued use. The skepticism towards harm reduction is based in part on the experience with low-yield tar/nicotine cigarettes, which were presumed to be associated with lower health risks than higher yield cigarettes and marketed as such by cigarette manufacturers. Only later did the field learn that these cigarettes were a deceptive way for cigarette manufacturers to allay the health concerns over cigarette smoking. Since this experience, there has been a proliferation of tobacco products that might potentially serve as a means to reduce tobacco harm. Some members of the tobacco control community believe that these products have great potential to reduce mortality and morbidity among smokers who completely switch to them. Others believe that we will be addicting another generation to tobacco products. This paper reviews the past history, the current tobacco landscape and controversies, and an approach that might rapidly reduce the yearly half-million deaths associated with cigarette smoking in the U.S.

Modeling smoking-attributable mortality among adults with major depression in the United States

Tobacco-related health disparities disproportionately affect smokers with major depression (MD). Although tobacco simulation models have been applied to general populations, to date they have not considered populations with a comorbid mental health condition. We developed and calibrated a simulation model of smoking and MD comorbidity for the US adult population using the 2005-2018 National Surveys on Drug Use and Health. We use this model to evaluate trends in smoking prevalence, smoking-attributable mortality and life-years lost among adults with MD, and changes in smoking prevalence by mental health status from 2018 to 2060. The model integrates known interaction effects between smoking initiation and cessation, and MD onset and recurrence. We show that from 2018 to 2060, smoking prevalence will continue declining among those with current MD. In the absence of intervention, people with MD will be increasingly disproportionately affected by smoking compared to the general population; our model shows that the smoking prevalence ratio between those with current MD and those without a history of MD increases from 1.54 to 2.42 for men and from 1.81 to 2.73 for women during this time period. From 2018 to 2060, approximately 484,000 smoking-attributable deaths will occur among adults with current MD, leading to 11.3 million life-years lost. Ambitious tobacco control efforts could alter this trajectory. With aggressive public health efforts, up to 264,000 of those premature deaths could be avoided, translating into 7.5 million life years gained. This model can compare the relative health gains across different intervention strategies for smokers with MD.