Toward a comprehensive long term nicotine policy

Research progress and prospect on the safety of heated tobacco products

In recent years, Heated tobacco products (HTP) have gradually entered the market and become more and more popular with consumers because of their low risk (compared with traditional cigarette). With the increasing popularity and proportion of HTP in the international market, people pay more and more attention to the safety evaluation of HTP, but there is still a lack of systematic review of HTP safety research. In this review, the harmful components of HTP, multi-organ functional programming effects (including respiratory system, cardiovascular system, etc.), and mechanism of the effect generation (including oxidative stress, inflammatory response, etc.) were systematically reviewed, the safety effects of HTP and traditional cigarettes were compared in detail, and the shortcomings and future research directions in the field of HTP safety were discussed. In summary, this review conforms to the general trend of contemporary "tobacco and health", helps people to understand and evaluate HTP more systematically, and provides a strong theoretical support and literature basis for the tobacco industry to carry out HTP risk assessment and exposure improvement.

Adult smokers' Complete Switching Away from Cigarettes at 6, 9, and 12 Months after Initially Purchasing a JUUL e-Cigarette

Background: Electronic nicotine delivery systems (ENDS) have the potential to benefit public health if smokers completely switch from cigarettes to ENDS. Methods: A cohort of adult smokers (age ≥ 21) who purchased a JUUL Starter Kit was followed for 12 months after the initial purchase. We defined "switching" as past-30-day abstinence from smoking (even if JUUL use had stopped), and analyzed factors associated with achievement and maintenance of self-reported repeated point-prevalence switching (RPPS) at three follow-ups, i.e., no past-30-day smoking at months 6, 9, and 12. Results: RPPS was reported by 21.6% of the 12,537 evaluable smokers. Smokers with lighter smoking history and lower cigarette dependence at baseline were more likely to report RPPS. RPPS was also associated with daily use of JUUL (Month-3: OR = 2.32, 95% CI = 2.02-2.68; Month-6: OR = 1.73, 95% CI = 1.42-2.10), and with greater subjective reinforcing effects from JUUL use (assessed by the mCEQ, Month-3: OR = 1.46, 95% CI = 1.38-1.56; Month-6: OR = 1.11; 95% CI = 1.02-1.20). Even among smokers who did not meet the criteria of RPPS (i.e., who smoked at least once), 35.5% reported past 30-day point-prevalence switching on at least one follow-up, and their cigarette consumption was substantially reduced compared to baseline. Conclusions: Approximately one-fifth of adult smokers reported 30-day point-prevalence abstinence at 6, 9, and 12 months after purchasing JUUL. Greater use of JUUL and stronger subjective reinforcing effects were associated with nonsmoking, validating the potential for ENDS to substitute for smoking, with potential for positive impacts on individual and population health.

Beyond the European Union Tobacco Products Directive: smokers' and recent quitters' support for further tobacco control measures (2016-2018)

BACKGROUND

Several measures recommended by the WHO Framework Convention on Tobacco Control have not been implemented in the European Union, despite changes in the legislation such as the Tobacco Products Directive (TPD). This study aims to understand smokers' and recent quitters' levels of support for tobacco control measures that go beyond the TPD during and after its implementation.

METHODS

Data from wave 1 (2016, n=6011) and wave 2 (2018, n=6027) of the EUREST-PLUS International Tobacco Control Policy Evaluation Project Six European Countries Survey, a cohort of adult smokers in Germany, Greece, Hungary, Poland, Romania, Spain were used to estimate the level of support for seven different tobacco control measures, overall and by country.

RESULTS

In 2018, the highest support was for implementing measures to further regulate tobacco products (50.5%) and for holding tobacco companies accountable for the harm caused by smoking (48.8%). Additionally, in 2018, 40% of smokers and recent quitters supported a total ban on cigarettes and other tobacco products within ten years, if assistance to quit smoking is provided. Overall, support for tobacco control measures among smokers and recent quitters after the implementation of the TPD remained stable over time.

CONCLUSION

There is considerable support among smokers and recent quitters for tobacco control measures that go beyond the current measures implemented. A significant percentage of smokers would support a ban on tobacco products in the future if the government provided assistance to quit smoking. This highlights the importance of implementing measures to increase smoking cessation in conjunction with other policies.

The Australia Smoking and Vaping Model: The Potential Impact of Increasing Access to Nicotine Vaping Products

BACKGROUND

We model the potential impact of relaxing current nicotine vaping product (NVP) restrictions on public health in Australia.

AIMS AND METHODS

A Restricted NVP Scenario was first developed to project current smoking and vaping rates, where a U.S. smoking model was calibrated to recent Australian trends. To model less restrictive NVP policies, a Permissive NVP Scenario applied rates of switching from smoking to vaping, initiation into NVP and cigarette use, and cessation from smoking and vaping based on U.S. trends. The model measures vaping risk relative to the excess mortality rate of smoking. The public health impacts are measured as the difference between smoking- and vaping-attributable deaths (SVADs) and life years lost (LYLs) in the Restricted and Permissive NVP Scenarios. Sensitivity analysis is conducted regarding the NVP excess risk and other factors.

RESULTS

Assuming an NVP excess risk of 5% that of smoking, 104.2 thousand SVADs (7.7% reduction) and 2.05 million LYLs (17.3% reduction) are averted during 2017-2080 in the Permissive NVP Scenario compared to the Restricted NVP Scenario. Assuming 40% NVP excess risk, 70 thousand SVADs and 1.2 million LYLs are averted. The impact is sensitive to the rate at which smokers switch to NVPs and quit smoking, and relatively insensitive to the smoking initiation and NVP initiation and cessation rates.

CONCLUSIONS

The model suggests the potential for public health gains to be achieved by relaxing NVP access regulations. However, the model would benefit from better information regarding the impact of NVPs on smoking under a relaxation of current restrictions.

IMPLICATIONS

Australia has implemented a strong array of cigarette-oriented policies, but has restricted access to NVPs. The Smoking and Vaping Model offers a framework for modeling hypothetical policy scenarios. The Australian model shows the potential for public health gains by maintaining cigarette-oriented policies while relaxing the current restrictive NVP policy. Modeling results under a permissive NVP policy are particularly sensitive to the estimated rates of smoking cessation and switching to vaping, which are not well established and will likely depend on past and future cigarette-oriented policies and the specific NVP policies implemented in Australia.

Clinical Pharmacology of Electronic Nicotine Delivery Systems (ENDS): Implications for Benefits and Risks in the Promotion of the Combusted Tobacco Endgame

Electronic nicotine delivery systems (ENDS) such as e-cigarettes and heated tobacco products are novel battery-operated devices that deliver nicotine without combustion of tobacco. Because cigarette smoking is sustained by nicotine addiction and the toxic combustion products are mainly responsible for the harmful effects of smoking, ENDS could be used to promote smoking cessation while exposing users to lower levels of toxicants compared with conventional cigarettes. The currently available evidence from clinical and observational studies indicates a potential role of e-cigarettes as smoking cessation aids, although many continue to use e-cigarettes long after quitting smoking. Nicotine and toxicant delivery vary considerably by device and depend on the characteristics of the e-liquid formulation. Because smokers tend to titrate their nicotine intake to maintain their desired pharmacologic effects, device and liquid characteristics need to be considered when using ENDS as an aid to quit smoking. Factors potentially limiting their use are the currently still unknown long-term safety of these products and concerns regarding widespread use among youth. Implications of clinical pharmacology data on ENDS for the cigarette endgame and regulation by the U.S. Food and Drug administration are discussed.

Sociodemographic Patterns of Exclusive, Dual, and Polytobacco Use Among U.S. High School Students: A Comparison of Three Nationally Representative Surveys

PURPOSE

This study examines sociodemographic patterns of exclusive/dual/polytobacco use among U.S. high school students using multiple national surveys.

METHODS

Using three national youth surveys (Population Assessment of Tobacco and Health [PATH] Wave 4 [2016-2017], 2017 Youth Risk Behavior Survey, and 2017 National Youth Tobacco Survey), we classified tobacco products into four groups: (1) electronic nicotine delivery systems (ENDS), (2) conventional cigarettes (CCs), (3) other combustible tobacco products, and (4) smokeless tobacco products. We created 16 categories of non/exclusive/dual/polytobacco use within the past 30 days using the four product groups and calculated weighted population prevalence by sex and race/ethnicity (all surveys) and parental education and income (PATH), based on variable availability.

RESULTS

The results from 9,331, 12,407, and 9,699 high school students in PATH, Youth Risk Behavior Survey, and National Youth Tobacco Survey, respectively, largely agreed and pointed to similar conclusions. ENDS was the most prevalent exclusive use product (3.8%-5.2% across surveys), with CCs falling to second or third (1.2%-2.0% across surveys). By sex, exclusive, dual, and poly smokeless tobacco product use were more common for males, whereas exclusive CC use was more common for females. By race/ethnicity, non-Hispanic Whites had a higher prevalence of exclusive ENDS use and ENDS/CC dual use than non-Hispanic Blacks. As income and parental education levels increased from low to high, the prevalence of exclusive CC use decreased, whereas the prevalence of exclusive ENDS use increased.

CONCLUSION

Understanding sociodemographic patterns of tobacco use can help identify groups who may be at greater risk for tobacco-related health outcomes.

Antiproliferative and antioxidant properties of nematocysts crude venom from jellyfish Acromitus flagellatus against human cancer cell lines

This study aimed to investigate the antiproliferative and antioxidant properties of crude venom from the nematocyst of Jellyfish Acromitus flagellates on human lung cancer (A549) and liver cancer (HepG2) cell lines. The prepared crude venom was subjected to analyses of the biochemical constituents, protein profiles, antioxidant and anticancer activities by standard methods. The extracted venom was pale-yellow in color and viscous/sticky. The biochemical composition such as, protein (1.547 mg/ml), lipid (0.039 mg/ml) and carbohydrate (0.028 mg/ml) was estimated. Protein profiles were determined by SDS PAGE, the result revealed that the molecular weight range from 205 - 3.5 kDa. The free radical scavenging activity was analyzed by the reducing potential (56.36%), DPPH (72.47%), hydroxyl (68.50%), superoxide anion (65.75%), and nitric oxide (33.04%). The cell viability was observed by using different concentrations (20 to 100 µg/ml) of crude venom on A549 and HepG2 cancer cell lines and the IC50 values were recorded in (60 μg/ml and 40 μg/ml) respectively, while it had none cytotoxic effects on Vero cell line up to the concentration of 90 μg/ml. These results suggest that crude venom from nematocyst of A. flagellatus possesses anti-cancer activity and able to develop novel drugs on marine-derived compounds.

Optical coherence tomography angiography to evaluate murine fetal brain vasculature changes caused by prenatal exposure to nicotine

Maternal smoking causes several defects ranging from intrauterine growth restriction to sudden infant death syndrome and spontaneous abortion. While several studies have documented the effects of prenatal nicotine exposure in development and behavior, acute vasculature changes in the fetal brain due to prenatal nicotine exposure have not been evaluated yet. This study uses correlation mapping optical coherence angiography to evaluate changes in fetal brain vasculature flow caused by maternal exposure to nicotine during the second trimester-equivalent of gestation in a mouse model. The effects of two different doses of nicotine were evaluated. Results showed a decrease in the vasculature for both doses of nicotine, which was not seen in the case of the sham group.

Trends in Tobacco Product Use Patterns Among U.S. Youth, 1999-2014

Introduction

We examined trends in seven mutually exclusive tobacco product use patterns (T-PUPs) in nationally representative samples of U.S. youth over time and age.

Methods

We used time varying effect modeling on National Youth Tobacco Surveys, 1999-2014 (N = 38662, 9-17 years, M = 15.02). Regression coefficients were estimated as a non-parametric function of time. T-PUPs were cigarette only, non-cigarette combustible only, noncombustible only, non-cigarette combustible and noncombustible dual, cigarette and noncombustible dual, cigarette and non-cigarette combustible dual, and POLY (i.e. cigarettes, non-cigarette combustibles, and noncombustibles) use.

Results

Among youth tobacco users, cigarette only use was the predominant T-PUP from 1999 to 2010. After 2010 and 2013, non-cigarette combustible only (AOR 1.38, CI = 1.02-1.87) and noncombustible only (AOR 1.57, CI = 1.00-2.45) use became more prevalent than cigarette only use. In 2011, dual and POLY T-PUPs were on the rise although not significantly different from cigarette only use. Cigarette only use was the predominant T-PUP among 11- to 17-year-old tobacco users. Non-cigarette combustible only (AOR 0.14, CI = 0.10-0.19), noncombustible only (AOR 0.01, CI = 0.008-0.02), non-cigarette combustible and noncombustible (AOR 0.01, CI = 0.01-0.03), cigarette and noncombustible (AOR 0.02, CI = 0.01-0.04), cigarette and non-cigarette combustible (AOR 0.32, CI = 0.24-0.43), and POLY (AOR 0.02, CI = 0.01-0.04) use were less prevalent than cigarette only use at age 17.

Conclusions

Non-cigarette, dual, and POLY T-PUPs are rising among youth tobacco users. Screening for all tobacco use and delivering treatment during pediatrician visits should be standard clinical practice.

Implications

Tracking trends in tobacco product use patterns (T-PUPs) over time and age is necessary to achieve Healthy People 2020 goal of reducing tobacco use among youth. Trends over time show a rise of non-cigarette T-PUPs especially noncombustible products but cigarette only use remains the most prevalent among 11- to 17-year-old tobacco users. The recent extension of FDA's regulatory jurisdiction over all tobacco products (e.g. e-cigarettes, hookah) is a step toward comprehensive tobacco control especially among youth. Public health practitioners should extend prevention and cessation efforts among youth to T-PUPs beyond exclusive cigarette smoking.

Perceptions of Alternative Tobacco Products, Anti-tobacco Media, and Tobacco Regulation among Young Adults: A Qualitative Study

Objectives With increased alternative tobacco product (ATP) use and lagging public health action, we explored perceptions of ATPs, anti-tobacco messaging, and tobacco regulation among young adults. Methods Semi-structured interviews were conducted with 60 Georgia college students aged 18-25 using: (1) cigarettes, little cigars/cigarillos (LCCs), smokeless tobacco, or e-cigarettes ≥15 days of the past 30; or (2) hookah ≥10 of the past 30 days (due to lower frequency of use). Of 99 participants recruited, 80 consented, and 60 participated. Results Participants were on average 21.01 years old (SD = 2.07), 56.7% women, and 65.0% black; 56.7% reported current use of cigarettes, 43.3% LCCs, 26.7% smokeless tobacco, 45.0% e-cigarettes, and 41.7% hookah. Cigarettes were perceived as most harmful to health and most addictive. E-cigarettes and hookah were generally regarded as lowest risk. Many indicated that ATP risk information was limited or inaccessible and that most anti-tobacco campaigns were irrelevant to ATPs. Participants requested more research and dissemination of evidence regarding ATP risks and need for ATP regulation. Conclusions In light of low risk perceptions regarding ATPs among young adults, research, anti-tobacco campaigns, and regulation must address their known and potential risks.

Smokers' risk perceptions and misperceptions of cigarettes, e-cigarettes and nicotine replacement therapies

INTRODUCTION AND AIMS

To identify the range and coherence of smokers and recent ex-smokers' general beliefs about the harms associated with smoking and the implications of these beliefs for their assessments of the relative harms and addictiveness of various nicotine containing products.

DESIGN AND METHODS

The study consisted of 18 single participant interviews with current smokers or vapers (13 M, 5 F) and three focus groups (15 M, 14 F) with current smokers/vapers and recent quitters. Both individual interviews and focus groups included semi-structured discussions of how nicotine and cigarette smoke cause disease and addiction, and a structured task involving rating the relative harmfulness and addictiveness of 17 nicotine products against a reference, popular, cigarette.

RESULTS

Most participants were able to give adequate accounts of what makes cigarette smoking harmful and addictive but this general knowledge was not consistently applied to making harmfulness and addictiveness judgements about specific products. Many participants applied simple affect-based heuristics to harmfulness and addictiveness judgments, even when they had apparently demonstrated more sophisticated knowledge earlier. Most used binary safe/dangerous thinking, with addictiveness and harmfulness strongly linked and a decoupling of satisfaction and addictiveness.

DISCUSSION AND CONCLUSIONS

Many smokers appear to have reasonable general knowledge of the risks of smoking but cannot reliably apply this knowledge to practical risk judgements. We need to rethink how we communicate with the public about the risks of smoking, and using other nicotine products, in ways that allow them to make more informed decisions about their smoking.

Taking Stock of Tobacco Control Program and Policy Science and Impact in the United States

The 60% decline in the prevalence of cigarette smoking among U.S. adults over the past 50 years represents a significant public health achievement. This decline was steered in part by national, state, and local tobacco control programs and policies, such as public education campaigns; widespread smoke-free air laws; higher cigarette prices that have been driven by large increases in federal, state, and local cigarette excise taxes; and other tobacco control policy and systems-level changes that discourage smoking. Using the MPOWER framework informed by the Centers for Disease Control and Prevention (CDC) Office on Smoking and Health and the World Health Organization (WHO), this paper reviews these accomplishments and identifies gaps in tobacco control policy implementation and additional research needed to extend these historic successes.

The Advertising Strategies of Early E-cigarette Brand Leaders in the United States

Objectives

We examined differential advertising strategies used by 4 major United States e-cigarette companies with differential affiliations with the traditional tobacco industry (ie, Njoy - independent, Blu - acquired, Vuse and MarkTen - launched by cigarette companies) over time.

Methods

We conducted a mixed-methods study regarding e-cigarette adspend, adspend per media channel (eg, TV, print), and advertising messaging strategies among these 4 top e-cigarette brands from January 2013 through December 2015.

Results

E-cigarette adspend increased from $59 million in 2013 to $91 million in 2014, followed by a sharp decline to $37 million in 2015. These companies showed distinct spending trajectories overall and across media channels, with Njoy and Vuse spending a higher proportion of their dollars on TV and Blu and MarkTen spending more on print. Marketing messages were also different by company. Key themes included switching from cigarettes (particularly by Njoy and Blu), circumventing smoke-free policies (particularly by Blu), and technological advancement (particularly by Vuse and MarkTen).

Conclusions

These e-cigarette brands have shifted their adspend, use of media channels, and advertising messaging strategies over time. Some differing strategies may reflect the different affiliations of each brand to the traditional cigarette industry.

A Risk Assessment Matrix for Public Health Principles: The Case for E-Cigarettes

Besides nicotine replacement therapies, a realistic alternative for smoking cessation or for smoking substitution may come from electronic cigarettes (ECs), whose popularity has been steadily growing. As for any emerging behaviour associated with exposure to inhalational agents, there is legitimate cause for concern and many health organizations and policy makers have pushed for restrictive policy measures ranging from complete bans to tight regulations of these products. Nonetheless, it is important to reframe these concerns in context of the well-known harm caused by cigarette smoking. In this article, we discuss key public health principles that should be considered when regulating ECs. These include the concept of tobacco harm reduction, importance of relative risk and risk continuum, renormalization of smoking, availability of low-risk product, proportionate taxation, and reassessment of the role of non-tobacco flavours. These public health principles may be systematically scrutinized using a risk assessment matrix that allows: (1) to determine the measure of certainty that a risk will occur; and (2) to estimate the impact of such a risk on public health. Consequently, the ultimate goal of responsible ECs regulation should be that of maximizing the favourable impact of these reduced-risk products whilst minimizing further any potential risks. Consumer perspectives, sound EC research, continuous post-marketing surveillance and reasonable safety and quality product standards should be at the very heart of future regulatory schemes that will address concerns while minimizing unintended consequences of ill-informed regulation.

DECOY: Documenting Experiences with Cigarettes and Other Tobacco in Young Adults

OBJECTIVES

We examined psychographic characteristics associated with tobacco use among Project DECOY participants.

METHODS

Project DECOY is a 2-year longitudinal mixed-methods study examining risk for tobacco use among 3418 young adults across 7 Georgia colleges/universities. Baseline measures included sociodemographics, tobacco use, and psychographics using the Values, Attitudes, and Lifestyle Scale. Bivariate and multivariable analyses were conducted to identify correlates of tobacco use.

RESULTS

Past 30-day use prevalence was: 13.3% cigarettes; 11.3% little cigars/cigarillos (LCCs); 3.6% smokeless tobacco; 10.9% e-cigarettes; and 12.2% hookah. Controlling for sociodemographics, correlates of cigarette use included greater novelty seeking (p < .001) and intellectual curiosity (p = .010) and less interest in tangible creation (p = .002) and social conservatism (p < .001). Correlates of LCC use included greater novelty seeking (p < .001) and greater fashion orientation (p = .007). Correlates of smokeless tobacco use included greater novelty seeking (p = .006) and less intellectual curiosity (p < .001). Correlates of e-cigarette use included greater novelty seeking (p < .001) and less social conservatism (p = .002). Correlates of hookah use included greater novelty seeking (p < .001), fashion orientation (p = .044), and self-focused thinking (p = .002), and less social conservatism (p < .001).

CONCLUSIONS

Psychographic characteristics distinguish users of different tobacco products.

Preferred flavors and reasons for e-cigarette use and discontinued use among never, current, and former smokers

OBJECTIVES

To compare e-cigarette flavors preferred and reasons for use and discontinued use across never, current, and former e-cigarette users and cigarette smokers.

METHODS

We recruited 1567 participants aged 18-34 years through Facebook ads targeting tobacco users and nonusers in August 2014 to complete an online survey. We assessed tobacco use, preferred flavors, and reasons for e-cigarette use and discontinued use.

RESULTS

Our sample was 49 % male, 87 % White; 56 % current cigarette smokers; and 53 % e-cigarette users. Current e-cigarette users used an average of 20.9 days in the past 30 (SD = 11.7) and 55.2 puffs/day (SD = 37.3). Compared to never and current smokers, former smokers used e-cigarettes more frequently (p's <0.001). Among users and nonusers, the most preferred was fruit flavors, and the most commonly reported reason for e-cigarette use was "they might be less harmful than cigarettes". The most endorsed reason for discontinued e-cigarette use was "using other tobacco products instead". Never, current, and former smokers had distinct reasons for e-cigarette use and discontinued use and differed in flavor preferences.

CONCLUSIONS

Regulating marketing and flavors may impact e-cigarette uptake by young adults.

A Risk-Continuum Categorization of Product Use Among US Youth Tobacco Users

INTRODUCTION

To examine prevalence and correlates of five mutually exclusive tobacco-use patterns among US youth tobacco users.

METHODS

A nationally representative sample of tobacco users (N = 3202, 9-17 years) was classified into five product-use patterns. Weighted multinominal and multivariate logistic regression models were used to examine prevalence of product-use patterns by gender, race and ethnicity, and grade level; and associations between product-use patterns and perceived accessibility of tobacco products, exposure and receptivity to pro-tobacco marketing, social benefits of smoking, and tobacco-associated risks.

RESULTS

Dual use (ie, use of two product categories) was the most prevalent pattern (30.5%), followed by non-cigarette combustible only (26.7%), polytobacco (ie, use of three product categories; 17.5%), cigarette only (14.9%), and noncombustible only (10.4%) use. Product-use patterns differed by gender, race, and ethnicity. Compared to cigarette only users, dual and polytobacco users were more likely to be exposed to and be receptive to pro-tobacco marketing, and were less likely to acknowledge tobacco-use related risks (Ps < .05).

CONCLUSIONS

Curbing tobacco use warrants research on users of more than one tobacco-product categories according to the risk-continuum categorization.

IMPLICATIONS

We present a risk-continuum categorization of product-use patterns among tobacco users not older than 17 years. We classify tobacco users into five mutually exclusive product-use patterns: cigarette only users, non-cigarette combustible only users, noncombustible only users, dual use, and polytobacco use. This categorization overcomes limitations in current literature on tobacco-use patterns, which include exclusion of certain products (eg, e-cigarettes) and product-use patterns (eg, exclusive users of non-cigarette products), and inconsistent classification of tobacco users. It is parsimonious yet complex enough to retain differential characteristics of sub-tobacco users based on number (single, dual, polytobacco) and categories (cigarettes, non-cigarette combustibles, noncombustibles) of tobacco products consumed.

The tobacco endgame: a qualitative review and synthesis

The tobacco endgame concept reorients discussion away from the persistent control of tobacco toward plans for ending the tobacco epidemic, and envisions a tobacco-free future. A variety of policy approaches have been proposed, with many offered prior to the introduction of the unifying term ‘endgame’. We conducted a qualitative synthesis of the literature on tobacco control endgames, and drew on media accounts and discussion of analogous ideas for illustrative purposes. We identified proposals focused on the product, user, market/supply or larger institutional structures. Research on public support for these proposals was limited, but suggestive of some public appetite for endgame ideas. Advocates should be encouraged to explore new policy options and consider the goal of a tobacco-free future.

The Reinforcing Effects of Nicotine in Humans and Nonhuman Primates: A Review of Intravenous Self-Administration Evidence and Future Directions for Research

INTRODUCTION

Cigarette smoking is largely driven by the reinforcing properties of nicotine. Intravenous (IV) self-administration procedures are the gold standard for investigating the reinforcing effects of psychoactive drugs. The goal of this review was to examine the results of published investigations of the reinforcing effects of nicotine measured using IV self-administration procedures in humans and nonhuman primates.

RESULTS

The body of literature using nonhuman primate subjects indicates nicotine functions as a positive reinforcer when available for self-administration via IV catheters. However, it can also be difficult to establish IV nicotine self-administration in nonhuman primates and sometimes supplemental strategies have been required (e.g., priming injections or food deprivation) before subjects acquire the behavior. Although the body of literature using human subjects is limited, the evidence indicates nicotine functions as a reinforcer via the IV route of administration in adult cigarette smokers. Rates of nicotine self-injection can be variable across subjects and responding is sometimes inconsistent across sessions in both humans and nonhuman primates.

CONCLUSIONS

The Family Smoking Prevention and Tobacco Control Act, enacted in 2009, gave the Food and Drug Administration regulatory authority over the manufacture, marketing, and distribution of tobacco products. Research examining the threshold reinforcing doses for initiation and maintenance of nicotine self-administration, comparisons of the reinforcing effects of nicotine in adolescent versus adult subjects, investigations of gender differences in the reinforcing effects of nicotine, and studies of the abuse liability of non-nicotine tobacco product constituents and their ability to alter the reinforcing effects of nicotine will inform potential tobacco regulatory actions.

Cigarette users' interest in using or switching to electronic nicotine delivery systems for smokeless tobacco for harm reduction, cessation, or novelty: a cross-sectional survey of US adults

INTRODUCTION

We examined: (a) current (past 30-day) smokers' interest in using or switching to electronic nicotine delivery systems (ENDS) or smokeless tobacco for various reasons; (b) correlates of interest in these products; and (c) subgroups of current smokers in relation to interest in these products.

METHODS

We conducted a cross-sectional survey assessing sociodemographics, tobacco use, interest in ENDS and smokeless tobacco among smokers, and knowledge about ENDS among 2,501 US adults recruited through an online consumer panel. We oversampled tobacco users (36.7% current cigarette smokers), ethnic minorities, and southeastern US state residents.

RESULTS

On average, participants were more interested in ENDS than smokeless tobacco across all reasons provided. Additionally, they were less interested in either product because of their potential use in places prohibiting smoking or due to curiosity and more interested in reducing health risk or cigarette consumption or to aid in cessation. We documented high rates (27.9%) of misbeliefs about Food and Drug Administration approval of ENDS for cessation, particularly among current smokers (38.5%). Also, 27.2% of current smokers had talked with a health care provider about ENDS, with 18.0% reporting that their provider endorsed ENDS use for cessation. Furthermore, cluster analyses revealed 3 groups distinct in their interest in the products, sociodemographics, and smoking-related characteristics.

CONCLUSIONS

This study highlights higher interest in ENDS versus smokeless tobacco and greater interest in both for harm reduction and cessation than due to novelty or smoking restrictions. Developing educational campaigns and informing practitioners about caveats around ENDS as cessation or harm reduction aids are critical.

Perceived harm of tobacco products and individual schemas of a smoker in relation to change in tobacco product use over one year among young adults

INTRODUCTION

Given increases in nondaily smoking and alternative tobacco use among young adults, we examined the nature of change of various tobacco product use among college students over a year and predictors of use at one-year follow-up.

METHODS

An online survey was administered to students at six Southeast colleges and universities (N = 4,840; response rate = 20.1%) in Fall 2010, with attempts to follow up in Fall 2011 with a random subsample of 2,000 participants (N = 718; response rate = 35.9%). Data were analyzed from 698 participants with complete data regarding tobacco, marijuana, and alcohol use over a one-year period, perceived harm of tobacco use, and schemas of a "smoker" (as per the Classifying a Smoker Scale).

RESULTS

Baseline predictors of current smoking at follow-up included being White (p = .001), frequency of smoking (p < .001), alternative tobacco use (p < .001), and perceived harm of smoking (p = .02); marginally significant predictors included marijuana use (p = .06) and lower scores on the Classifying a Smoker Scale (p = .07). Baseline predictors of current smoking at follow-up among baseline nondaily smokers included more frequent smoking (p = .008); lower Classifying a Smoker Scale score was a marginally significant predictor (p = .06). Baseline predictors of alternative tobacco use at follow-up included being male (p = .007), frequency of smoking (p = .04), alternative tobacco use (p < .001), and frequency of alcohol use (p = .003); marginally significant predictors included marijuana use (p = .07) and lower perceived harm of smokeless tobacco (p = .06) and cigar products (p = .08).

CONCLUSIONS

Tobacco control campaigns and interventions might target schemas of a smoker and perceived risks of using various tobacco products, even at low levels.

Perceived harm, addictiveness, and social acceptability of tobacco products and marijuana among young adults: marijuana, hookah, and electronic cigarettes win

BACKGROUND

There has been an increase in non-daily smoking, alternative tobacco product and marijuana use among young adults in recent years.

OBJECTIVES

This study examined perceptions of health risks, addictiveness, and social acceptability of cigarettes, cigar products, smokeless tobacco, hookah, electronic cigarettes, and marijuana among young adults and correlates of such perceptions.

METHODS

In Spring 2013, 10,000 students at two universities in the Southeastern United States were recruited to complete an online survey (2,002 respondents), assessing personal, parental, and peer use of each product; and perceptions of health risks, addictiveness, and social acceptability of each of these products.

RESULTS

Marijuana was the most commonly used product in the past month (19.2%), with hookah being the second most commonly used (16.4%). The least commonly used were smokeless tobacco products (2.6%) and electronic cigarettes (4.5%). There were high rates of concurrent product use, particularly among electronic cigarette users. The most positively perceived was marijuana, with hookah and electronic cigarettes being second. While tobacco use and related social factors, related positively, influenced perceptions of marijuana, marijuana use and related social factors were not associated with perceptions of any tobacco product. Conclusions/Importance: Marketing efforts to promote electronic cigarettes and hookah to be safe and socially acceptable seem to be effective, while policy changes seem to be altering perceptions of marijuana and related social norms. Research is needed to document the health risks and addictive nature of emerging tobacco products and marijuana and evaluate efforts to communicate such risks to youth.

Emerging nicotine delivery products. Implications for public health

The idea of clean nicotine delivery systems that would satisfy nicotine craving and promote smoking cessation has been considered as a possible public health tool for many years. Nicotine medications have been useful for smoking cessation but have not found widespread popularity among smokers, perhaps because of slow nicotine delivery and other sensory characteristics that differ from cigarettes. Traditional smokeless tobacco delivers as much nicotine as cigarettes and has been advocated for harm reduction but contains carcinogenic nitrosamines and has not been proven to promote cessation. Furthermore, there is concern that dual use of smokeless tobacco and cigarettes may inhibit quitting smoking. Newer oral dissolvable tobacco products contain lower levels of toxicants than other smokeless tobacco but also deliver much less nicotine and have not been popular with consumers. Electronic cigarettes that aerosolize nicotine without generating toxic tobacco combustion products have become quite popular and hold promise as a way to attract smokers away from cigarettes, although efficacy in promoting smoking cessation has not yet been demonstrated. There are concerns about safety of long-term use, and there is evidence that youth, including nonsmokers, are taking up e-cigarette use. E-cigarettes are marketed for use when one cannot smoke conventional cigarettes, and such use might result in more persistent cigarette smoking. Although their benefits and risks are being vigorously debated, e-cigarettes or other clean nicotine delivery devices could play an important role as an adjunct to a U.S. Food and Drug Administration regulatory intervention to make cigarettes less addictive and in this context could contribute to the end of cigarette smoking and smoking-induced disease.

In and across bureaucracy: structural and administrative issues for the tobacco endgame

This article assesses the structural choices for the proposed tobacco endgame strategies. I focus on the issues associated with particular structural choices for the location of the implementation. Specifically, I discuss issues related to implementation of the endgame within a specific single agency, and issues related to a more widespread, broad implementation involving several agencies. Where appropriate, I provide examples of how the dynamics discussed would apply to particular endgame strategies. Issues related to design, administration, authority and finances are raised.

Nicotine yesterday, today, and tomorrow: a global review

This intentionally selective global review reflects the views and frustrations of a public health physician with 45 years of frontline experience in tobacco control. In particular, it focuses on the nexus between research and policy and the long periods between relevant discoveries and application as policy. Consideration is given to the relative neglect of the possibility of reducing the carcinogenicity and toxicity of the cigarette on the grounds that it is the preferred source of nicotine for the global majority of nicotine users. Although the outcome of such change is unquantifiable, there is much in cigarette smoke that can be changed to make it less carcinogenic and less toxic. It is difficult to think of excuses for accepting the status quo.

Nicotine reduction: strategic research plan

BACKGROUND

Reducing nicotine content in cigarettes and other combustible products to levels that are not reinforcing or addictive has the potential to substantially reduce tobacco-related morbidity and mortality. The authority to reduce nicotine levels as a regulatory measure is provided in the U.S. Family Smoking Prevention and Tobacco Control Act and is consistent with the general regulatory powers envisioned under the relevant articles of the World Health Organization's Framework Convention on Tobacco Control. Many experts have considered reducing nicotine in cigarettes to be a feasible national policy approach, but more research is necessary.

PURPOSE

This article describes proceedings from a conference that had the goals of identifying specific research gaps, describing methods and measures to consider for addressing these gaps, and considering ways to foster collaboration.

RESULTS AND CONCLUSION

Identified research gaps included determining the dose of nicotine that would be optimal for reducing and extinguishing cigarette use, examining approaches for reducing nicotine levels in the general and special populations of smokers, understanding how constituents other than nicotine may contribute to the reinforcing effects of tobacco, and identifying unintended consequences to determine ways to mitigate them. Methods that can be used ranged from brain imaging to large human clinical trials. The development and availability of valid biomarkers of exposure and effect are important. Infrastructures to facilitate collaboration need to be established.

Research required for the effective implementation of the framework convention on tobacco control, articles 9 and 10

This paper is part of a series of articles intended to set out the research questions that are relevant to the successful implementation of the various provisions of the Framework Convention on Tobacco Control (FCTC). This paper focuses on issues affecting Articles 9 and 10 of the FCTC. This paper focuses on the research that is most important for most countries, rather than on what is desirable in countries with high levels of research capacity. Articles 9 and 10 of the FCTC address the regulation of contents and emissions of tobacco products and regulation of tobacco product disclosure. Such regulation will be essential if the long-term objective of reducing the danger of tobacco products is to be achieved. There are many components of tobacco and tobacco smoke that are excessively toxic and dangerous to the user. Many of these components are carcinogenic and addictive and can be removed or reduced substantially with current known technology. The fact that these components remain in tobacco and tobacco smoke at levels that are unnecessarily dangerous is precisely the reason why the successful implementation of Articles 9 and 10 of the FCTC is important to tobacco control. This paper discusses the scientific challenges involved in successfully implementing Articles 9 and 10 of the FCTC, which focuses on regulating carcinogens and toxins in tobacco and tobacco smoke, the abuse liability of tobacco products, and the additives and engineering features in tobacco products that make tobacco products appealing to future consumers. The research issues we focus on are those required to support the early stages of regulation. As regulation proceeds, new and more sophisticated research questions will undoubtedly emerge.

Dose-response effects of spectrum research cigarettes

INTRODUCTION

Experimental cigarettes are needed to conduct studies examining the effects of varying doses of nicotine content on smoking behavior. The National Institute on Drug Abuse contracted with Research Triangle Institute to make such cigarettes available to researchers. The goal of this study was to determine whether cigarettes that vary in nicotine content produce an expected dose-response effect.

METHOD

Two studies were conducted. The first study recruited subjects from 3 sites and consisted of a single, within-subject laboratory session. Subjects first smoked 4 puffs on their usual-brand cigarette and then in double-blind, random-order, smoked 4 puffs on each experimental cigarette that contained either low nicotine (LN, 0.4 mg/g), intermediate nicotine (IN, 5.7-5.8 mg/g), or high nicotine (HN, 11.4-12.8 mg/g). Each puffing bout was separated by a 30-min interval. Subjects completed questionnaires and were assessed for vital signs after each cigarette. The second study involved 1 site and used a between-subject design in which subjects were assigned to 1 of the 3 experimental cigarettes for 1 week. Subjective responses and biomarkers of exposure were assessed.

RESULTS

In the first study, significant dose-response effects were observed, particularly between the LN and HN cigarettes. The second study showed decreases in cigarette smoking and exposure biomarkers predominantly in the LN group, with no changes in the HN cigarette group.

CONCLUSIONS

These results are similar to those observed in prior literature, confirming that these experimental cigarettes can be used safely and with the expected pharmacological effects.

The combined effect of very low nicotine content cigarettes, used as an adjunct to usual Quitline care (nicotine replacement therapy and behavioural support), on smoking cessation: a randomized controlled trial

AIM

To determine the combined effect of very low nicotine content (VLNC) cigarettes and usual Quitline care [nicotine replacement therapy (NRT) and behavioural support] on smoking abstinence, in smokers motivated to quit.

DESIGN

Single-blind, parallel randomized trial.

SETTING

New Zealand. PARTICIPANTS Smokers who called the Quitline for quitting support were randomized to either VLNC cigarettes to use whenever they had an urge to smoke for up to 6 weeks after their quit date, in combination with usual Quitline care (8 weeks of NRT patches and/or gum or lozenges, plus behavioural support) or to usual Quitline care alone.

MEASUREMENTS

The primary outcome was 7-day point-prevalence smoking abstinence 6 months after quit day. Secondary outcomes included continuous abstinence, cigarette consumption, withdrawal, self-efficacy, alcohol use, serious adverse events and views on the use of the VLNC cigarettes at 3 and 6 weeks and 3 and 6 months.

FINDINGS

A total of 1410 participants were randomized (705 in each arm), with a 24% loss to follow-up at 6 months. Participants in the intervention group were more likely to have quit smoking at 6 months compared to the usual care group [7-day point-prevalence abstinence 33 versus 28%, relative risk (RR) = 1.18, 95% confidence interval (CI): 1.01, 1.39, P = 0.037; continuous abstinence 23 versus 15%, RR = 1.50, 95% CI: 1.20, 1.87, P = 0.0003]. The median time to relapse in the intervention group was 2 months compared to 2 weeks in the usual care group (P < 0.0001).

CONCLUSIONS

Addition of very low nicotine content cigarettes to standard Quitline smoking cessation support may help some smokers to become abstinent.

Qualitative exploration of public and smoker understanding of, and reactions to, an endgame solution to the tobacco epidemic

Background

There is increasing interest in ending the tobacco epidemic and in applying ‘endgame’ solutions to achieve that goal at national levels. We explored the understanding of, and reactions to, a tobacco-free vision and an endgame approach to tobacco control among New Zealand smokers and non-smokers.

Methods

We recruited participants in four focus groups held in June 2009: Māori (indigenous people) smokers (n=7); non-Māori smokers (n=6); Māori non-smokers (n=7); and non-Māori non-smokers (n=4). Participants were from the city of Whanganui, New Zealand. We introduced to them the vision of a tobacco-free New Zealand and the concept of a semi-autonomous agency (Tobacco-Free Commission [TFC]) that would control the tobacco market as part of an endgame approach.

Results

There was mostly strong support for the tobacco-free New Zealand vision among all groups of participants. The reason most commonly given for supporting the vision was to protect children from tobacco. Most participants stated that they understood the TFC concept and reacted positively to it. Nevertheless, rather than focusing on organisational or structural arrangements, participants tended to focus on supporting the specific measures which a future TFC might facilitate such as plain packaging of tobacco products. Various concerns were also raised around the TFC, particularly around the feasibility of its establishment.

Conclusions

We were able to successfully communicate a complex and novel supply-side focused tobacco control policy intervention to smokers and non-smokers. The findings add to the evidence from national surveys that there is public support, including from smokers, for achieving a tobacco-free vision and using regulatory and policy measures to achieve it. Support for such measures may be enhanced if they are clearly communicated and explained with a rationale which stresses protecting children and future generations from tobacco smoking.

Use of emerging tobacco products in the United States

This paper provides the first nationally representative estimates for use of four emerging products. Addressing the issue of land-line substitution with cell phones, we used a mixed-mode survey to obtain two representative samples of US adults. Of 3,240 eligible respondents contacted, 74% completed surveys. In the weighted analysis, 13.6% have tried at least one emerging tobacco product; 5.1% snus; 8.8% waterpipe; 0.6% dissolvable tobacco products; 1.8% electronic nicotine delivery systems (ENDS) products. Daily smokers (25.1%) and nondaily smokers (34.9%) were the most likely to have tried at least one of these products, compared to former smokers (17.2%) and never smokers (7.7%), P<.001. 18.2% of young adults 18-24 and 12.8% of those >24 have tried one of these products, P<.01. In multivariable analysis, current daily (5.5, 4.3-7.6), nondaily (6.1, 4.0-9.3), and former smoking status (2.7, 2.1-3.6) remained significant, as did young adults (2.2, 1.6-3.0); males (3.5, 2.8-4.5); higher educational attainment; some college (2.7, 1.7-4.2); college degree (2.0, 1.3-3.3). Use of these products raises concerns about nonsmokers being at risk for nicotine dependence and current smokers maintaining their dependence. Greater awareness of emerging tobacco product prevalence and the high risk demographic user groups might inform efforts to determine appropriate public health policy and regulatory action.

Non-cigarette tobacco products: what have we learnt and where are we headed?

A wide variety of non-cigarette forms of tobacco and nicotine exist, and their use varies regionally and globally. Smoked forms of tobacco such as cigars, bidis, kreteks and waterpipes have high popularity and are often perceived erroneously as less hazardous than cigarettes, when in fact their health burden is similar. Smokeless tobacco products vary widely around the world in form and the health hazards they present, with some clearly toxic forms (eg, in South Asia) and some forms with far fewer hazards (eg, in Sweden). Nicotine delivery systems not directly reliant on tobacco are also emerging (eg, electronic nicotine delivery systems). The presence of such products presents challenges and opportunities for public health. Future regulatory actions such as expansion of smoke-free environments, product health warnings and taxation may serve to increase or decrease the use of non-cigarette forms of tobacco. These regulations may also bring about changes in non-cigarette tobacco products themselves that could impact public health by affecting attractiveness and/or toxicity.

A systematic review of nicotine by inhalation: is there a role for the inhaled route?

INTRODUCTION

A considerable minority of adults remain addicted to smoking cigarettes despite substantial education and public health efforts. Nicotine replacement therapies have only modest long-term quit rates. The pulmonary route of nicotine delivery has advantages over other routes. However, there are regulatory and technical barriers to the development of pulmonary nicotine delivery devices, and hence, none are commercially available. Current knowledge about pulmonary nicotine delivery is scattered throughout the literature and other sources such as patent applications. This review draws together what is currently known about pulmonary nicotine delivery and identifies potential ways that deep lung delivery can be achieved with a simple portable device.

AIMS

To systematically review clinical trials of nicotine inhalers, determine whether they delivered nicotine via the lung, and identify ways that pulmonary delivery of medicinal nicotine might be achieved and the technical issues involved.

METHODS

Systematic search of Medline and Embase.

RESULTS

Thirty-eight trials met the inclusion criteria. Cough, reflex interruption of smooth inspiration, and throat scratch limited the usefulness of nicotine inhalers. The pharmacokinetic profiles of portable nicotine inhalers were inferior to smoking, but among commercially available products, electronic cigarettes are currently the most promising.

CONCLUSIONS

Pulmonary nicotine delivery might be maximized by use of nicotine salts, which have a more physiological pH than pure nicotine, by ensuring the mass of the particles is optimal for alveolar absorption, and by adding flavoring agents. Metered-dose inhalers potentially can deliver nicotine more efficiently than other nicotine products, facilitating smoking cessation and improving smokers' lives.

Tobacco and nicotine product testing

INTRODUCTION

Tobacco product testing is a critical component of the Family Smoking Prevention and Tobacco Control Act (FSPTCA), which grants the Food and Drug Administration the authority to regulate tobacco products. The availability of methods and measures that can provide accurate data on the relative health risks across types of tobacco products, brands, and subbrands of tobacco products on the validity of any health claims associated with a product, and on how consumers perceive information on products toxicity or risks is crucial for making decisions on the product's potential impact on public health. These tools are also necessary for making assessments of the impact of new indications for medicinal products (other than cessation) but more importantly of tobacco products that may in the future be marketed as cessation tools.

OBJECTIVE

To identify research opportunities to develop empirically based and comprehensive methods and measures for testing tobacco and other nicotine-containing products so that the best science is available when decisions are made about products or policies.

METHODS

Literature was reviewed to address sections of the FSPTCA relevant to tobacco product evaluation; research questions were generated and then reviewed by a committee of research experts.

RESULTS

A research agenda was developed for tobacco product evaluation in the general areas of toxicity and health risks, abuse liability, consumer perception, and population effects.

CONCLUSION

A cohesive, systematic, and comprehensive assessment of tobacco products is important and will require building consensus and addressing some crucial research questions.

Research opportunities related to establishing standards for tobacco products under the Family Smoking Prevention and Tobacco Control Act

INTRODUCTION

This paper was written in response to a request from the U.S. National Cancer Institute. The goal is to discuss some research directions related to establishing tobacco product standards under the Family Smoking Prevention and Tobacco Control Act, which empowers the U.S. Food and Drug Administration to regulate tobacco products. Potential research related to tobacco product ingredients, nicotine, and harmful or potentially harmful constituents of tobacco products is discussed.

DISCUSSION

Ingredients, which are additives, require less attention than nicotine and harmful or potentially harmful constituents. With respect to nicotine, the threshold level in tobacco products below which dependent users will be able to freely stop using the product if they choose to do so is a very important question. Harmful and potentially harmful constituents include various toxicants and carcinogens. An updated list of 72 carcinogens in cigarette smoke is presented. A crucial question is the appropriate levels of toxicants and carcinogens in tobacco products. The use of carcinogen and toxicant biomarkers to determine these levels is discussed.

CONCLUSIONS

The need to establish regulatory standards for added ingredients, nicotine, and other tobacco and tobacco smoke constituents leads to many interesting and potentially highly significant research questions, which urgently need to be addressed.

Daring to dream: reactions to tobacco endgame ideas among policy-makers, media and public health practitioners

Background

Tobacco control strategies have mainly targeted reducing demand. Supply-side focused measures, though less familiar, deserve consideration, particularly to achieve 'endgame' tobacco control aims (e.g. achieving close to zero smoking prevalence). We explored attitudes towards supply-side focused 'endgame' tobacco control approaches and how they can be best communicated with senior policymakers, journalists, and public health practitioners.

Methods

We identified five supply-side focused approaches which could potentially lead to the tobacco endgame: two structural models and three discrete actions. The structural models were: (i) a Nicotine Authority to coordinate tobacco control activities and regulate the nicotine/tobacco market for public health aims; and (ii) a Tobacco Supply Agency acting as a monopoly purchaser of tobacco products and controlling the tobacco supply for public health aims. The actions were: (a) allocating progressively reducing tobacco product import quotas (the 'sinking lid') until importation and commercial sale of tobacco products ceased; (b) making tobacco companies responsible for reducing smoking prevalence with stringent financial penalties if targets were missed; and (c) new laws to facilitate litigation against tobacco companies. These approaches were presented as means to achieve a tobacco free New Zealand by 2020 to 19 senior policymakers, journalists, and public health physicians in two focus groups and eight interviews, and their reactions sought.

Results

The tobacco-free vision was widely supported. Participants engaged fully with the proposed tobacco control approaches, which were viewed as interesting or even intriguing. Most supported increasing the focus on supply-side measures. Views differed greatly about the desirability, feasibility and likely effectiveness of each approach. Participants identified a range of potential barriers to implementation and challenges to successfully advocating and communicating these approaches. The current framing of tobacco as a risky but legal commodity was noted as an important potential barrier to implementing endgame approaches.

Conclusions

Endgame tobacco control approaches were considered to be viable policy options. Further policy analysis, research and public discussion are needed to develop endgame approaches. A significant change in the public framing of tobacco may be a prerequisite for implementing endgame solutions.

Nicotine reduction revisited: science and future directions

Regulation of nicotine levels in cigarettes and other tobacco products is now possible with the passage of the Family Smoking Prevention and Tobacco Control Act (FSPTCA) in 2009, giving the US Food and Drug Administration (FDA) authority to regulate tobacco products, and with Articles 9-11 of the WHO Framework Convention on Tobacco Control. Both regulatory approaches allow establishing product standards for tobacco constituents, including nicotine. The FSPTCA does not allow nicotine levels to be decreased to zero, although the FDA has the authority to reduce nicotine yields to very low, presumably non-addicting levels. The proposal to reduce levels of nicotine to a level that is non-addicting was originally suggested in 1994. Reduction of nicotine in tobacco products could potentially have a profound impact on reducing tobacco-related morbidity and mortality. To examine this issue, two meetings were convened in the US with non-tobacco-industry scientists of varied disciplines, tobacco control policymakers and representatives of government agencies. This article provides an overview of the current science in the area of reduced nicotine content cigarettes and key conclusions and recommendations for research and policy that emerged from the deliberations of the meeting members.

Clinical trials methods for evaluation of potential reduced exposure products

Potential reduced exposure products (PREPs) to tobacco toxicants may have promise in reducing tobacco-related morbidity or mortality or may promote greater harm to individuals or the population. Critical to determining the risks or benefits from these products are valid human clinical trial PREP assessment methods. Such an assessment involves determining the effects of these products on biomarkers of exposure and effect, which serve as proxies for harm, and assessing the potential for consumer uptake and abuse of the product. This article identifies critical methodologic issues associated with PREP assessments, reviews the methods that have been used to assess PREPs, and describes the strengths and limitations of these methods. Additionally, recommendations are provided for clinical trial PREP assessment methods and future research directions in this area based on this review and on the deliberations from a National Cancer Institute sponsored Clinical Trials PREP Methods Workshop.

The Strategic Dialogue on Tobacco Harm Reduction: a vision and blueprint for action in the US

The issues related to tobacco harm reduction continue to challenge the tobacco control research and policy communities. The potential for combusting tobacco products to reduce exposure and risk remains largely unknown, but this has not stopped manufacturers from offering such products making these claims. The role of oral tobacco products in a harm reduction regimen has also been a source of dialogue and debate. Within the last few years, major cigarette manufacturing companies have begun selling smokeless products for the first time, claiming to target current cigarette smokers. Other cigarette manufacturers are also offering smokeless products in markets around the world. The harm reduction debate has at times been divisive. There has been no unifying set of principles or goals articulated to guide tobacco control efforts. In particular, the research needs are extraordinarily high in order to drive evidence-based policy in this area and avoid the mistakes made with "light" cigarettes. This paper discusses recommendations from a strategic dialogue held with key, mostly US-based tobacco control researchers and policy makers to develop a strategic vision and blueprint for research, policy and communications to reduce the harm from tobacco for the US. Short-term and long-term objectives are described.

Progressive commercial cigarette yield reduction: biochemical exposure and behavioral assessment

BACKGROUND

Mandated reduction of exposure to nicotine and other cigarette toxins has been proposed as a possible national regulatory strategy. However, tapering using lower yield commercial cigarettes may not be effective in reducing nicotine or tar exposure due to compensatory smoking behavior. We examined the effects of gradual reduction of nicotine yield in commercial cigarettes on smoking behavior, with an assessment of nicotine intake and exposure to tobacco smoke toxins.

METHODS

This 10-week longitudinal study of 20 smokers involved smoking the usual brand followed by different brands with progressively lower machine-determined yields, ranging from 0.9 to 0.1 mg nicotine, each smoked for 1 week. Subjects were followed for 4 weeks after returning to smoking the usual brand (or quitting). Smoking behaviors, biomarkers of tobacco smoke exposure, and cardiovascular effects were measured.

FINDINGS

Cotinine and other biomarkers of smoke exposure remained unchanged comparing the usual brand with the 0.4 mg nicotine brands. A 30% to 40% decrease in nicotine, carbon monoxide, and carcinogen exposure comparing 0.1 mg nicotine cigarettes with baseline was observed. Self-efficacy was significantly increased and dependence decreased after tapering.

IMPLICATIONS

We confirm prior cross-sectional population and experimental studies showing complete compensation for cigarettes down to the 0.4 mg nicotine range. Nicotine and tobacco toxin exposure were substantially reduced while smoking 0.1 mg nicotine cigarettes. Our data suggest that the degree of nicotine dependence of smokers may be lowered with progressive yield tapering. Gradual tapering of smokers from regular to ultralow nicotine yield commercial cigarettes might facilitate smoking cessation and warrants future research.

Disrupting nicotine reinforcement: from cigarette to brain

Cigarette smoking is a tenacious addiction that is maintained to a significant extent by the reinforcing effects of nicotine. An emerging theme in smoking cessation treatment is the development of methods for interfering with these reinforcing effects. By attenuating nicotine reinforcement, treatments may enhance a smoker's chances of successfully remaining abstinent. Several treatment approaches will be described, including the use of denicotinized cigarettes, nicotine vaccines, nicotinic receptor agonists and antagonists, and modulators of brain reinforcement processes. These techniques highlight the numerous sites along the path between the cigarette and the brain that can be targeted for intervention. In addition to unimodal therapies, treatment combinations will be discussed that might more effectively block cigarette reward and thereby further enhance smoking abstinence.

If nicotine is a developmental neurotoxicant in animal studies, dare we recommend nicotine replacement therapy in pregnant women and adolescents?

Tobacco use in pregnancy is a leading cause of perinatal morbidity and contributes in major ways to attention deficit hyperactivity disorder, conduct disorders and learning disabilities that emerge in childhood and adolescence. Over the past two decades, animal models of prenatal nicotine exposure have demonstrated that nicotine is a neurobehavioral teratogen that disrupts brain development by preempting the natural, neurotrophic roles of acetylcholine. Through its actions on nicotinic cholinergic receptors, nicotine elicits abnormalities of neural cell proliferation and differentiation, promotes apoptosis and produces deficits in the number of neural cells and in synaptic function. The effects eventually compromise multiple neurotransmitter systems because of the widespread regulatory role of cholinergic neurotransmission. Importantly, the long-term alterations include effects on reward systems that reinforce the subsequent susceptibility to nicotine addiction in later life. These considerations strongly question the appropriateness of nicotine replacement therapy (NRT) for smoking cessation in pregnant women, especially as the pharmacokinetics of the transdermal patch may actually enhance fetal nicotine exposure. Further, because brain maturation continues into adolescence, the period when smoking typically commences, adolescence is also a vulnerable period in which nicotine can change the trajectory of neurodevelopment. There are also serious questions as to whether NRT is actually effective as an aid to smoking cessation in pregnant women and adolescents. This review considers the ramifications of the basic science findings of nicotine's effects on brain development for NRT in these populations.

The possible role of ammonia toxicity on the exposure, deposition, retention, and the bioavailability of nicotine during smoking

A complete and rigorous review is presented of the possible effect(s) of ammonia on the exposure, deposition and retention of nicotine during smoking and the bioavailability of nicotine to the smoker. There are no toxicological data in humans regarding ammonia exposure within the context of tobacco smoke. Extrapolation from occupational exposure of ammonia to smoking in humans suggests minimal, non-toxicological effects, if any. No direct study has examined the effect of the ammonia on the total rate or amount of nicotine reaching the arterial bloodstream or brains of smokers. Machine-smoking methods have been reported which accurately quantify >99% of the nicotine in mainstream (MS) smoke for a wide variety of commercial and test cigarettes, including a series of experimental cigarettes having a range in MS smoke ammonia yields using the US Federal Trade Commission (FTC) protocol. However, the actual exposure of nicotine to smokers depends on their own smoking behavior. The nicotine ring system is relatively thermally stable. Protonated nicotine forms nicotine which evaporates before the nicotine ring system decomposes. The experimental data indicate that neither nicotine transfer from tobacco to MS smoke nor nicotine bioavailability to the smoker increases with an increase in any of the following properties: tobacco soluble ammonia, MS smoke ammonia, "tobacco pH" or "smoke pH" at levels found in commercial cigarettes. Gas phase nicotine deposits primarily in the mouth and upper respiratory tract. To the extent that ammonia increases the deposition of nicotine in the buccal cavity and upper respiratory tract during smoking, the total rate and amount of nicotine into the arterial bloodstream and to the central nervous system will decrease. Charged nicotine analogues are actively transported in a number of tissues. This active transport system appears to be insensitive to pH and the form of nicotine in the biological milieu, suggesting that protonated nicotine may be a substrate for active transport. Neither "smoke pH" of commercial cigarettes nor "smoke pHeff" nor the fraction of non-protonated nicotine in tobacco smoke particulate matter are useful, practical smoke parameters for providing understanding or predictability of nicotine bioavailability to smokers. Greater than 95% of both ammonia and nicotine are in the gas phase of environmental tobacco, and both are likely to deposit in the buccal cavity and upper respiratory tract following exposure.