Adolescent smokers' response to reducing the nicotine content of cigarettes: Acute effects on withdrawal symptoms and subjective evaluations

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.

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.

Qualitative reactions to a low nicotine product standard for cigarettes from adolescents and young adults living in the United States who smoke

The Biden Administration is considering a low nicotine product standard for cigarettes. This qualitative study examined reactions to a nicotine reduction policy among adolescents and young adults (AYA) who smoke cigarettes. After completing a lab study involving masked exposure either to low nicotine or normal nicotine research cigarettes and unmasked exposure to e-cigarettes varying in nicotine concentration and flavor, we conducted follow-up semi-structured interviews (N = 25) to explore participants' knowledge, attitudes, and perceptions of a low nicotine product standard and their anticipated tobacco use behavior after policy implementation. Interviews were audio-recorded, transcribed verbatim, double-coded, and analyzed using reflexive thematic analysis. Nearly half of participants supported the policy because they thought it would prevent young people from starting smoking and/or would help people quit. Reasons some participants opposed the policy included beliefs that adults should have the choice to smoke or that a nicotine reduction policy is counterintuitive because the government benefits from cigarette sales. Others believed the policy would be ineffective because youth could circumvent the policy (e.g., illicit market) or would increase their smoking to maintain the same nicotine level. Almost half of participants said they would quit smoking while the other half said they would continue smoking, although potentially reduce their smoking. Overall, our qualitative findings point to the need for pre-policy media campaigns targeting AYA who smoke to minimize negative reactions, dispel fears, and correct misperceptions as well as encourage quitting and provide information on accessing cessation resources.

Electronic Nicotine Delivery Systems: An Updated Policy Statement From the American Association for Cancer Research and the American Society of Clinical Oncology

Combustible tobacco use has reached historic lows, demonstrating the importance of proven strategies to reduce smoking since publication of the 1964 Surgeon General's report. In contrast, the use of electronic nicotine delivery systems (ENDS), specifically e-cigarettes, has grown to alarming rates and threatens to hinder progress against tobacco use. A major concern is ENDS use by youth and adults who never previously used tobacco. While ENDS emit fewer carcinogens than combustible tobacco, preliminary evidence links ENDS use to DNA damage and inflammation, key steps in cancer development. Furthermore, high levels of nicotine can also increase addiction, raise blood pressure, interfere with brain development, and suppress the immune system. The magnitude of long-term health risks will remain unknown until longitudinal studies are completed. ENDS have been billed as a promising tool for combustible tobacco cessation, but further evidence is needed to assess their potential efficacy for adults who smoke. Of concern, epidemiological studies estimate that approximately 15%-42% of adults who use ENDS have never used another tobacco product, and another 36%-54% dual use both ENDS and combustible tobacco. This policy statement details advances in science related to ENDS and calls for urgent action to end predatory practices of the tobacco industry and protect public health. Importantly, we call for an immediate ban on all non-tobacco-flavored ENDS products that contain natural or synthetic nicotine to reduce ENDS use by youth and adults who never previously used tobacco. Concurrently, evidence-based treatments to promote smoking cessation and prevent smoking relapse to reduce cancer incidence and improve public health remain top priorities for our organizations. We also recognize there is an urgent need for research to understand the relationship between ENDS and tobacco-related disparities.

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.

Non-nicotine constituents in cigarette smoke extract enhance nicotine addiction through monoamine oxidase A inhibition

Tobacco addiction has been largely attributed to nicotine, a component in tobacco leaves and smoke. However, extensive evidence suggests that some non-nicotine components of smoke should not be overlooked when considering tobacco dependence. Yet, their individual effect and synergistic effect on nicotine reinforcement remain poorly understood. The study herein focused on the role of non-nicotine constituents in promoting the effects of nicotine and their independent reinforcing effects. Denicotinized cigarettes were prepared by chemical extracting of cut tobacco, and the cigarette smoke extracts (CSE, used as a proxy for non-nicotine ingredients) were obtained by machine-smoking the cigarettes and DMSO extraction. The compositions of harmful components, nicotine, and other minor alkaloids in both cut tobacco and the CSE of experimental denicotinized cigarettes were examined by GC-MS, and compared with 3R4F reference cigarettes. individually and in synergy with nicotine were determined by conditioned place preference (CPP), dopamine (DA) level detection, the open field test (OFT), and the elevated plus maze (EPM). Finally, the potential enhancement mechanism of non-nicotinic constituents was investigated by nicotine metabolism and monoamine oxidase A (MAOA) activity inhibition in the striatum of mice and human recombinant MAOA. Thenicotine content in smoke from the experimental denicotinized cigarettes (under ISO machine-smoking conditions) was reduced by 95.1% and retained most minor alkaloids, relative to the 3R4F reference cigarettes. It was found that non-nicotine constituents increased acute locomotor activities. This was especially pronounced for DA levels in NAc and CPP scores, decreased the time in center zone. There were no differences in these metrics with DNC group when compared to the NS group. Non-nicotine constituents alone did not show reinforcing effects in CPP or striatum DA levels in mice. However, in the presence of nicotine, non-nicotine constituents further increased the reinforcing effects. Furthermore, non-nicotine constituents may enhance nicotine's reinforcing effects by inhibiting striatum MAOA activity rather than affecting nicotine metabolism or total striatum DA content in mice. These findings expand our knowledge of the effect on smoking reinforcement of non-nicotine constituents found in tobacco products.

Electronic Nicotine Delivery Systems: An Updated Policy Statement from the American Association for Cancer Research and the American Society of Clinical Oncology

Combustible tobacco use has reached historic lows, demonstrating the importance of proven strategies to reduce smoking since publication of the 1964 Surgeon General's report. In contrast, the use of electronic nicotine delivery systems (ENDS), specifically e-cigarettes, has grown to alarming rates and threatens to hinder progress against tobacco use. A major concern is ENDS use by youth and adults who never previously used tobacco. While ENDS emit fewer carcinogens than combustible tobacco, preliminary evidence links ENDS use to DNA damage and inflammation, key steps in cancer development. Furthermore, high levels of nicotine can also increase addiction, raise blood pressure, interfere with brain development, and suppress the immune system. The magnitude of long-term health risks will remain unknown until longitudinal studies are completed. ENDS have been billed as a promising tool for combustible tobacco cessation, but further evidence is needed to assess their potential efficacy for adults who smoke. Of concern, epidemiological studies estimate that approximately 15% to 42% of adults who use ENDS have never used another tobacco product, and another 36% to 54% "dual use" both ENDS and combustible tobacco. This policy statement details advances in science related to ENDS and calls for urgent action to end predatory practices of the tobacco industry and protect public health. Importantly, we call for an immediate ban on all non-tobacco-flavored ENDS products that contain natural or synthetic nicotine to reduce ENDS use by youth and adults who never previously used tobacco. Concurrently, evidence-based treatments to promote smoking cessation and prevent smoking relapse to reduce cancer incidence and improve public health remain top priorities for our organizations. We also recognize there is an urgent need for research to understand the relationship between ENDS and tobacco-related disparities.

Withdrawal Symptoms among Cigarette and Waterpipe Smokers: A Study in Natural Setting

Background:

The rates of tobacco use, including cigarette and waterpipe smoking, are surging in the Eastern Mediterranean region. The use of these products causes nicotine dependence that makes even short-term tobacco abstinence difficult due to aversive symptoms. During the daytime fasting of the month of “Ramadan”, people accept significant disruption in regular activities, including tobacco smoking. Thus, daytime during Ramadan (before sunset) is likely associated with abstinence symptoms emerging among tobacco smokers. We assessed this hypothesis by measuring tobacco/nicotine abstinence symptoms and craving among smokers of cigarettes or waterpipes during Ramadan.

Methods:

A cross-sectional survey-based study was conducted on a convenience sample of adults. Participants were assessed for general information about tobacco smoking, dependence, and nicotine desire or craving, and withdrawal symptoms using the Minnesota Nicotine Withdrawal Scale (MNWS) and the Tiffany-Drobes Questionnaire on Smoking Urges.

Results:

The study sample included 632 exclusive cigarette smokers and 161 exclusive waterpipe tobacco smokers. After fasting and abstaining from tobacco during the day, approximately 75% of cigarette smokers and 20% of waterpipe smokers reported smoking within the first 30 minutes. In addition, 10% of cigarette smokers and 30% of waterpipe smokers reported smoking within the first 60 minutes. Regarding smoking urge, no significant difference was found between cigarette and waterpipe smokers. For nicotine craving and withdrawal, significant differences between cigarette and waterpipe smokers were found when comparing mean scores for each of the following items: (i) urge to smoke, (ii) craving nicotine, (iii) hunger, (iv) desire for sweets, and (v) depression/feeling blue (P-values < 0.05).

Conclusion:

This study provided evidence from the month of Ramadan that waterpipe smoking is associated with abstinence-induced smoking urge and withdrawal symptoms that are comparable to cigarette smoking. More interdisciplinary research must be focused on developing interventions to reduce tobacco smoking, including waterpipe.

A review of the evidence on cigarettes with reduced addictiveness potential

Background

In May 2018, the Secretariat for the World Health Organization Framework Convention on Tobacco Control convened a meeting to discuss the potential for reducing the addictiveness of tobacco products. A central focus was to review research findings on the behavioral effects of reducing the addictiveness of cigarettes.

Methods

This manuscript reports the results of a review of the behavioral science literature, updated through April 2021, with special attention to both the potential benefits and unintended consequences of reducing nicotine in cigarettes.

Results

Available evidence suggests that reducing nicotine content in cigarettes to very low levels could benefit public health in three primary ways, by 1) decreasing uptake of regular smoking, 2) decreasing the amount people smoke, and 3) increasing the likelihood of smoking cessation. Current evidence also suggests that reducing nicotine in cigarettes may produce similar benefits across many important subpopulations of people who smoke, including those with psychiatric comorbidities, those who use other substances, those with low socioeconomic status, young people, people who smoke infrequently and people who prefer menthol cigarettes. Cigarette nicotine reduction could also lead to some undesirable outcomes, such as experiencing withdrawal, product manipulation, an illicit market, and harm misperceptions; strategies that may mitigate each are discussed.

Conclusion

Overall, behavioral research suggests product standards that limit the nicotine content of combusted tobacco products could render cigarettes and similar products less addictive. The availability of legal, non-combusted products that effectively substitute for cigarettes and the dissemination of public health campaigns that clarify misperceptions about the relationship between nicotine, tobacco and disease may facilitate the extent to which a nicotine reduction policy reduces smoking.

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.

Cigarette use, anxiety, and insomnia from adolescence to early adulthood: A longitudinal indirect effects test

BACKGROUND

Cigarette use during adolescence has been linked to increased risk for insomnia symptoms, but limited work has examined factors that may account for this association. Adolescent cigarette use and anxiety symptoms characterized by physiological hyperarousal evidence bidirectional associations, as do anxiety symptoms and insomnia symptoms. This suggests that adolescent cigarette use, anxiety symptoms characterized by physiological hyperarousal, and insomnia symptoms may increase and maintain one another. The current study tests physiological hyperarousal anxiety symptoms as a potential indirect effect in the cigarette-insomnia symptoms link across adolescence and young adulthood.

METHODS

We examined data from adolescents and young adults from Waves 1, 2, 3 and 4 of the National Longitudinal Study of Adolescent to Adult Health (N = 2,432 with full data). Insomnia symptoms were assessed at baseline (ages 12-16 years), 1 year later (13-17 years), and 14 years after baseline (26 - 30 years) among a nationally representative sample of adolescents. Cigarette use was assessed at baseline, 1 year later, 6 years after baseline, and 14 years after baseline. Anxiety symptoms were assessed at baseline and 1 year later.

RESULTS

Structural equation models indicated that anxiety symptoms exerted an indirect effect on the longitudinal associations between adolescent cigarette use and adult insomnia symptoms. Anxiety symptoms and cigarette use evidenced bidirectional associations during adolescence.

CONCLUSIONS

These results suggest that increases in anxiety symptoms characterized by physiological hyperarousal may be one mechanism whereby cigarette use during adolescence is associated with increased insomnia symptoms during early adulthood. Prevention efforts aimed at reducing cigarette use during adolescence may have long term additional benefits for anxiety symptoms and insomnia symptoms.

Responses to Gradual and Immediate Reduction of Nicotine in Cigarettes in Young Versus Older Adult Smokers

INTRODUCTION

As the FDA works to determine whether a nicotine reduction policy would benefit public health, one key question is whether to mandate an immediate or gradual reduction in nicotine levels in cigarettes. The aim of this study was to determine whether the effects of gradual versus immediate nicotine reduction on cigarettes per day (CPD), total nicotine equivalents, and subjective responses differed in younger adults versus older adults.

METHODS

Using data from a recent randomized trial conducted in the United States (N = 1250) that switched smokers over a 20-week period to very low nicotine content (VLNC) cigarettes either immediately, gradually (via monthly reductions in nicotine content), or not at all (control condition, normal nicotine content research cigarette), we analyzed the moderating effect of age (age 18-24 or 25+).

RESULTS

For both age groups, CPD in the immediate condition was significantly lower relative to gradual condition (estimated mean difference of 6.3 CPD in young adults, 5.2 CPD in older adults; p's < .05). Younger and older adults in the immediate and gradual reduction conditions had lower total nicotine equivalents at Week 20 (all p's < .05) than those in the control condition; age group did not moderate this effect. Positive subjective responses to cigarettes were lower among young adults relative to older adults in the immediate condition.

CONCLUSIONS

These results indicate that an immediate reduction in nicotine would result in beneficial effects in both young and older adults. Young adults show less positive subjective effects of smoking following switching to VLNC cigarettes relative to older adults.

IMPLICATIONS

As researchers work to understand how a potential reduced-nicotine product standard for cigarettes may affect public health, one question is whether nicotine should be reduced immediately or gradually. This study demonstrates that both young and older adults who were switched immediately to the lowest content of nicotine smoked fewer CPD and had lower nicotine intake than those in the gradual condition. Furthermore, young adults appear to show lower positive subjective effects following switching to VLNC cigarettes relative to older adults. This is consistent with previous work demonstrating that young people appear to show lower abuse liability for VLNC cigarettes.

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.

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.

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.

Nicotine reduction does not alter essential value of nicotine or reduce cue-induced reinstatement of nicotine seeking

Reduction of nicotine content in tobacco products is a regulatory control strategy intended to decrease smoking dependence, and is hypothesized to produce gradual reductions of nicotine intake. Rats were initially trained to self-administer 0.06 mg/kg/infusion nicotine (Phase 1), which was followed by a threshold procedure to determine nicotine demand via a behavioral economics (BE) paradigm (Phase 2). Rats then either self-administered the training dose (high dose group), or were switched to a low dose of nicotine (0.001 mg/kg/infusion; low dose group) in Phase 3. Both groups then underwent a second threshold procedure and demand curves were re-determined (Phase 4). In Phase 5, responding for nicotine was extinguished over the course of 21 sessions. Cue-induced reinstatement was then evaluated (Phase 6). Rats in the low dose group maintained a steady amount of infusions, and thus, did not compensate for nicotine reduction. Rats in the low dose group also showed similar demand elasticity and nicotine seeking (Phase 6) compared to the high dose group, indicating that nicotine reduction did not decrease nicotine demand or seeking. Further, both groups displayed resistance to extinction, indicating that nicotine reduction did not facilitate extinction learning. These results suggest that although compensation of intake does not occur, decreasing the dose of nicotine does not alter nicotine reinforcement value or relapse vulnerability. Further, these results indicate persistence of nicotine-motivated behavior after self-administration of a low nicotine dose. Translationally, these results suggest that alternative strategies may be needed to achieve positive smoking cessation outcomes.

Nicotine Reduction in Cigarettes: Literature Review and Gap Analysis

BACKGROUND

The US Food and Drug Administration (FDA) is considering reducing nicotine levels in cigarettes to "minimally or non-addictive levels." However, important research gaps remain, and the FDA must determine when the available research is sufficient to support moving forward.

METHODS

The authors conducted a systematic review of research articles in PubMed relating to nicotine reduction. Building on a review of risk assessment best practices, the authors also developed a risk assessment framework for tobacco regulation and used it to guide a gap analysis of nicotine reduction research.

RESULTS

The final sample consisted of 78 articles. The majority examined either nicotine dependence on very low nicotine cigarettes (VLNCs) or markers of potential health effects of using VLNCs. One-third of the identified articles reported results from four large randomized controlled trials (RCTs). While these studies report promising results and suggest that a nicotine reduction rule would be a powerful tool to reduce cigarette smoking, our gap analysis suggests that there is a need for studies that better reflect the use and availability of a wide range of tobacco/nicotine products and the potential for dual- or multi-product use.

CONCLUSION

The current body of research on nicotine reduction is weighted towards RCTs, which is appropriate for a policy that has not yet been implemented anywhere in the world. The FDA must consider a wide range of factors that may impact a product standard's public health impact, including those difficult to assess in RCTs, such as a nicotine reduction rule's impact on smoking initiation and relapse.

IMPLICATIONS

This systematic review presents a gap analysis based on a risk assessment framework to help identify remaining research priorities to inform FDA's potential product standard to reduce nicotine levels in cigarettes. Quickly addressing those gaps would support the FDA's effort to develop a nicotine reduction product standard that will be effective and withstand legal challenges.

Behavioral economic demand and delay discounting are differentially associated with cigarette dependence and use in adolescents

INTRODUCTION

The Reinforcer Pathology Model describes how two behavioral economic processes, increased sensitivity to immediate rewards (delay discounting) and excessive reward derived from a substance (demand), both contribute to problematic patterns of substance use. In a novel application of this model, the current cross-sectional study examined how these distinct processes relate to different facets of cigarette use in adolescents.

METHODS

Adolescent daily cigarette smokers ages 15 to 19 (Mean age 17.7, N = 50) completed a laboratory assessment of demand using a Cigarette Purchase Task for their usual brand cigarettes and an adjusting-amount delay discounting task. Demand was conceptualized as two factors (Amplitude and Persistence) and delay discounting was calculated as Area Under the Curve (log AUC). The two factors of demand and discounting AUC were included as statistical predictors of level of cigarette dependence and average number of cigarettes smoked per day in linear regression models.

RESULTS

Amplitude of demand was marginally significant predictor (p = .06) of cigarettes smoked per day whereas neither Persistence of demand nor delay discounting significantly predicted this outcome. Both Amplitude of demand and delay discounting, but not Persistence, were associated with level of cigarette dependence. The effects of amplitude of demand and delay discounting on cigarette dependence or use did not significantly interact.

CONCLUSIONS

Results of this study suggest that amplitude of cigarette demand may be a risk factor for both cigarette consumption and dependence, while discounting - a known risk factor for cigarette initiation - may relate specifically to level of dependence.

Effects of Cigarette Nicotine Content and Menthol Preference on Perceived Health Risks, Subjective Ratings, and Carbon Monoxide Exposure Among Adolescent Smokers

INTRODUCTION

Minimal research exists on adolescent smokers' perceptions of very low-nicotine-content (VLNC) cigarettes. As approximately half of adolescent smokers prefer menthol cigarettes, it is important to consider the influence of menthol preference on VLNC cigarette perceptions and to what extent menthol preference may affect VLNC smoking behavior. This study examined the effects of cigarette nicotine content and menthol preference or menthol smoking on health risk perceptions, subjective ratings, and carbon monoxide (CO) boost in adolescent smokers.

METHODS

Across two counterbalanced sessions, adolescent smokers sampled VLNC and normal nicotine content (NNC) research cigarettes following overnight abstinence. Cigarettes were mentholated or non-mentholated consistent with participants' usual brand. In each session, participants smoked the research cigarette and then completed the Perceived Health Risk Scale and Cigarette Evaluation Scale. Breath CO readings were obtained pre- and post-smoking. Mixed-factor ANOVA tests compared outcomes with cigarette type (VLNC vs. NNC) as the within-subjects factor and menthol preference as the between-subjects factor.

RESULTS

Participants (N = 50) were M = 17.7 years old, smoked M = 8.2 cigarettes/day, and 56% typically smoked menthol cigarettes. Participants reported lower risk of developing lung cancer, other cancers, emphysema, bronchitis, and heart disease (ps ≤ .05) when smoking VLNC cigarettes relative to NNC cigarettes. Perceived risk of addiction and stroke did not differ by nicotine content. Menthol preference or menthol smoking did not moderate risk perceptions, subjective ratings, or CO boost.

CONCLUSIONS

Adolescents may incorrectly perceive that VLNC cigarettes are less harmful products. Health communication campaigns could help to correct VLNC misperceptions and potentially minimize unintended consequences of a nicotine reduction policy.

Anticipated Effects of Nicotine Reduction on Youth Smoking Initiation and Maintenance

This commentary summarizes emerging findings on the potential impact of a nicotine reduction policy on youth and young adults. We conclude that: (1) adolescent smokers and nonsmokers alike are likely to be less sensitive to reinforcement from very low nicotine content (VLNC) cigarettes compared with adults; (2) reducing nicotine in cigarettes to 0.4 mg/g would reduce the abuse potential of cigarettes in adolescents and young adults; (3) findings to date do not support concerns that nicotine reduction leads to compensatory smoking in young smokers; and (4) if the scope of a reduced nicotine product standard were applied to all combusted tobacco products, that would likely maximize public health benefit of this policy.

Effects of repetitive transcranial magnetic stimulation on nicotine consumption and craving: A systematic review

We performed a systematic review of the studies employing repetitive transcranial magnetic stimulation (rTMS) in subjects with smoking addiction. High-frequency (HF) rTMS over the prefrontal cortex (PFC), in particular the left dorsolateral PFC (DLPFC), might represent a save and innovative treatment tool for tobacco consumption and craving in nicotine-dependent otherwise healthy people. rTMS can be effective for this indication also in patients with schizophrenia, but the results are conflicting and sufficient evidence from large-scale trials is still lacking. Promising results have been obtained using particular techniques for brain stimulation, such as deep rTMS and theta burst stimulation. Multiple-target HF rTMS can also have a potential in smoking cessation. fMRI and EEG recordings have proven to be useful for objectively assessing the treatment effects. TMS is likely to be most effective when paired with an evidence-based self-help intervention, cognitive-behavioral interventions and nicotine replacement therapy. However, the most recent studies employed different protocols and yielded heterogeneous results, which should be replicated in further controlled studies with larger sample sizes and rigorous standards of randomization. To date, no recommendation other than that a possible efficacy of HF-rTMS of the left DLPFC can be made for alternative rTMS procedures in nicotine craving and consumption.