Increased e-cigarette use prevalence is associated with decreased smoking prevalence among US adults.

BACKGROUND: If US adults who smoke cigarettes are switching to e-cigarettes, the effect may be observable at the population level: smoking prevalence should decline as e-cigarette prevalence increases, especially in sub-populations with highest e-cigarette use. This study aimed to assess such effects in recent nationally-representative data. METHODS: We updated a prior analysis with the latest available National Health Interview Survey data through 2022. Data were cross-sectional estimates of the yearly prevalence of smoking and e-cigarette use, respectively, among US adults and among specific age, race/ethnicity, and sex subpopulations. Non-linear models were fitted to observed smoking prevalence in the pre-e-cigarette era, with a range of 'cut-off' years explored (i.e., between when e-cigarettes were first introduced to when they became widely available). These trends were projected forward to predict what smoking prevalence would have been if pre-e-cigarette era trends had continued uninterrupted. The difference between actual and predicted smoking prevalence ('discrepancy') was compared to e-cigarette use prevalence in each year in the e-cigarette era to investigate whether the observed decline in smoking was statistically associated with e-cigarette use. RESULTS: Observed smoking prevalence in the e-cigarette era was significantly lower than expected based on pre-e-cigarette era trends; these discrepancies in smoking prevalence grew as e-cigarette use prevalence increased, and were larger in subpopulations with higher e-cigarette use, especially younger adults aged 18-34. Results were robust to sensitivity tests varying the analysis design. CONCLUSIONS: Population-level data continue to suggest that smoking prevalence has declined at an accelerated rate in the last decade in ways correlated with increased uptake of e-cigarette use.

What Substances Are Adolescents Vaping? Estimating Nicotine-Specific and Cannabis-Specific Vaping from US National Youth Surveys.

BACKGROUND: Youth use of electronic cigarettes ("e-cigarettes") is an ongoing concern. Vaping is usually assumed to be of nicotine, but survey responses may also include vaping of non-nicotine substances (particularly cannabis), which can impose different risks. The current study quantifies the proportions of nicotine-specific and cannabis-specific vaping among adolescents. METHODS: Data from the Monitoring the Future (MTF) 2021 survey were analyzed with respect to the substance vaped: nicotine, cannabis, or flavoring only. Past-30-day (P30D) nicotine-specific vaping (exclusively, or also having vaped other substances) and cannabis-specific vaping were calculated. Results were also broken down by grade level, cigarette smoking history (current, former, or never), and frequency of e-cigarette use (<20 vs. 20+ days in P30D). RESULTS: Among 4706 P30D e-cigarette users, 84.2% vaped nicotine; the remaining 15.8% reported not vaping any nicotine in P30D. Cannabis vaping was reported by 48.4% of P30D vapers. Vaping both nicotine and cannabis in P30D was more common in current and former smokers than in never-smokers, and in frequent vapers (of any substance). Conversely, never-smokers were more commonly vaping cannabis but not nicotine, compared to current and former smokers. Supplementary NYTS 2022 analyses were consistent with these findings. CONCLUSIONS: A notable proportion of self-reported P30D vapers reported not vaping nicotine; nearly half vaped cannabis. Capturing the variety of substances used in vaping devices is imperative for accurate public health surveillance of both nicotine and cannabis vaping among US adolescents, considering their different respective harms and regulatory frameworks.

Population-level counterfactual trend modelling to examine the relationship between smoking prevalence and e-cigarette use among US adults.

BACKGROUND: Studies have suggested that some US adult smokers are switching away from smoking to e-cigarette use. Nationally representative data may reflect such changes in smoking by assessing trends in cigarette and e-cigarette prevalence. The objective of this study is to assess whether and how much smoking prevalence differs from expectations since the introduction of e-cigarettes. METHODS: Annual estimates of smoking and e-cigarette use in US adults varying in age, race/ethnicity, and sex were derived from the National Health Interview Survey. Regression models were fitted to smoking prevalence trends before e-cigarettes became widely available (1999-2009) and trends were extrapolated to 2019 (counterfactual model). Smoking prevalence discrepancies, defined as the difference between projected and actual smoking prevalence from 2010 to 2019, were calculated, to evaluate whether actual smoking prevalence differed from those expected from counterfactual projections. The correlation between smoking discrepancies and e-cigarette use prevalence was investigated. RESULTS: Actual overall smoking prevalence from 2010 to 2019 was significantly lower than counterfactual predictions. The discrepancy was significantly larger as e-cigarette use prevalence increased. In subgroup analyses, discrepancies in smoking prevalence were more pronounced for cohorts with greater e-cigarette use prevalence, namely adults ages 18-34, adult males, and non-Hispanic White adults. CONCLUSION: Population-level data suggest that smoking prevalence has dropped faster than expected, in ways correlated with increased e-cigarette use. This population movement has potential public health implications.

Assigning dose of nicotine gum by time to first cigarette.

INTRODUCTION: Nicotine gum, a proven effective aid to cessation, comes in two doses: 2-mg and 4-mg. Assignment to the higher dose has traditionally been based on daily cigarette consumption. This paper evaluates efficacy of the gum when the 4-mg dose is assigned based on time to first cigarette (TTFC) being ≤ 30 min. METHODS: In a secondary analysis of a randomized, double-blind, placebo-controlled trial that allocated smokers randomly to placebo, 2-mg, or 4-mg gum (Garvey, A. J., Kinnunen, T., Nordstrom, B. L., Utman, C. H., Doherty, K., Rosner, B., et al. (2000). Effects of nicotine gum dose by level of nicotine dependence. Nicotine & Tobacco Research, 2, 53-63. doi:10.1080/14622200050011303), we evaluated outcomes when 4-mg gum was given to subjects with TTFC ≤ 30 (n = 158, placebo n = 159). RESULTS: Active treatment doubled or tripled abstinence rates versus placebo. This also held among smokers with a history of treatment failure. The effect of 4-mg gum was significant among light smokers (<25 CPD) with TTFC ≤ 30; 2-mg gum was not. CONCLUSION: This analysis suggests that assigning dose of nicotine gum based on TTFC is an effective and appropriate means of dose allocation.

Crossing a border for a low-cost, high-risk environment: smoking status and excessive drinking among young adults in Tijuana.

This study examines the drinking and smoking behavior of 2,311 college-age adults traveling from San Diego, California, to Tijuana, Mexico (December 2006 to December 2008). We describe this Border sample's drinking history and smoking status and estimate multivariate models of evening drinking participation and, conditional on drinking, blood alcohol concentration. Noting limitations, we present implications for identifying young adults at high risk for alcohol and tobacco use, particularly females, and lay the foundation for further research examining young adults? alcohol and tobacco use in reduced price scenarios.

Rapid absorption of nicotine from new nicotine gum formulations.

RATIONALE: A clinically limiting feature of currently-available nicotine gum is its slow rate of nicotine delivery and consequently slow onset of therapeutic effects. Previous research suggested that a nicotine hydrogen tartrate gum (NHTG1) that delivered nicotine more rapidly provided more effective craving relief. A subsequent gum formulation (NTHG2) was developed to further increase speed of delivery. OBJECTIVE: Compare the plasma nicotine absorption and clinical tolerability of NHTG2 to NHTG1 and Nicorette FreshMint. METHODS: A single-dose, randomized, crossover study evaluated the early kinetics of nicotine absorption and tolerability of 4 mg NHTG2 compared to NHTG1 and Nicorette. RESULTS: NHTG2 gum reached higher Cmax (p=0.059 versus Nicorette; p=0.006 versus NHTG1) and delivered significantly more nicotine than Nicorette or NHTG1 within the first 10-30 min of chewing (AUCs0-10, 0-30) and overall (AUC0-180). NHT gums and Nicorette were well tolerated, with little difference in their AE profiles. CONCLUSIONS: Study results indicate that NHTG2 gum provided more rapid uptake of nicotine in blood without notable decreases in tolerability. To the extent that rate of delivery and onset of therapeutic effects are related, these gums would be expected to provide more rapid therapeutic effects.

UK smokers' and ex-smokers' reactions to cigarettes promising reduced risk.

AIMS: This study evaluated the impact of exposure to information about a novel cigarette claiming to reduce exposure to tobacco toxins ('potential reduced exposure product' cigarette or PREP-C) on smokers' and ex-smokers' perceptions of PREP-C, on quit interest among smokers and on interest in resuming smoking among ex-smokers. DESIGN AND PARTICIPANTS: A random digit-dialed telephone survey was conducted in the United Kingdom with 500 current smokers and 106 ex-smokers who had quit within the last 2 years. INTERVENTION: The interviewer described a novel cigarette that claimed to significantly reduce exposure to smoke toxins. MEASUREMENTS: Respondents' interest in purchasing the PREP-C, beliefs about its safety and risk reduction and smokers' quit interest, as measured by stage of change, before and after exposure to PREP-C information. FINDINGS: Among smokers, 76.5% were interested in purchasing PREP-C; interest did not vary by stage of change. Almost all smokers (90.6%) thought PREP-C was safer than regular cigarettes, with 5.4% indicating that the health risks were equivalent to not smoking at all. Exposure to PREP-C description did not change quit interest. Among ex-smokers, 5.6% believed PREP-C carried no health risk and 7.1% expressed purchase interest. CONCLUSIONS: Smokers and ex-smokers interpreted claims of reduced toxin exposure as reduced health risk and responded positively towards PREP-Cs. With the increasing introduction of PREP-Cs world-wide, evaluation of these products and their claims on quitting among smokers and on relapse among ex-smokers is a matter of public health urgency.

Smokers' preferences for medicinal nicotine vs smokeless tobacco.

OBJECTIVE: To assess and compare smokers' interest in medicinal nicotine (MN) and smokeless tobacco (SLT) and preference between them. METHODS: Two studies presented US smokers verbally with MN and SLT concepts and assessed their appeal as smoking substitutes. Both studies evaluated interest and preference between products, with attention to the hypothesis that SLT is preferred over MN. RESULTS: Study 1 described well-known MN and SLT products. Fifty-nine percent preferred MN and 22% SLT. Study 2 presented less familiar MN and SLT products. Forty-four percent preferred MN and 35% SLT. CONCLUSIONS: The data show that MN products, as presented to smokers in this study, are perceived to be more appealing to smokers.

Trends in serious quit attempts in the United States, 2009-14.

BACKGROUND AND AIMS: Quitting smoking is the most potent way to reduce the health risks associated with smoking cigarettes, and public health objectives in the United States include dramatic increases in the proportion of smokers making a serious quit attempt each year. The US Centers for Disease Control and Prevention (CDC) has, since 2000, set as its Healthy People 2020 objective to encourage 80% of smokers to make a serious quit attempt per year. This study assessed the trend in quit attempts from 2009 to 2014. DESIGN: We examined the percentage of US smokers making a serious quit attempt each year from 2009 to 2014 from the repeating cross-sectional National Health Interview Survey (NHIS). SETTING: United States. PARTICIPANTS: The number of qualifying respondents per year ranged from 5748 in 2010 to 7219 in 2012, with a total of 40 362 respondents included in the analysis. MEASUREMENTS: Respondents were deemed to have made a serious quit attempt if they were either current smokers who reported that they stopped smoking for more than 1 day in the past 12 months because they were trying to quit smoking, or reported being former smokers (smoked 100+ cigarettes life-time, but now not smoking) who quit in the past year. FINDINGS: Analyses of trends from 2009 to 2014 showed an overall linear increase in quit attempts [odds ratio (OR) = 1.02, 95% confidence interval (CI) = 1.01-1.04, P = 0.0075], but also a quadratic trend (OR = 1.01, 95% CI = 1.00-1.02, P = 0.0189). CONCLUSIONS: The proportion of US smokers making a serious quit attempt has increased since 2009, due to an upward trend since 2011. The 2014 serious quit attempt rate was 55.0%. These rates are still below the Healthy People 2020 objective of 80% of smokers making a serious quit attempt per year.

Drug counselor report of adolescents abuse of nicotine replacement therapy.

BACKGROUND: Nicotine replacement products (NRT) are formulated and marketed to reduce their abuse liability among adolescents. Few studies have examined the extent of adolescent abuse. The objective of this manuscript is to describe the youth abuse rate for NRT and other over-the-counter (OTC) abusable substances. METHODS: Two cross-sectional telephone surveys of Safe and Drug Free School Coordinators were conducted in 1996/7 (N = 562) and 1998/9 (N = 501). Abuse of NRT and other OTC drugs and circumstances surrounding NRT abuse was ascertained. RESULTS: NRT abuse rates were low and did not change significantly between the two surveys (2.7% in 1996/7 to 4.6% in 1998/9). NRT abuse rates were well below those of other OTC abusable substances (e.g., diet pills and inhalants). CONCLUSIONS: Concerns over promotion of youth dependence to nicotine by offering the sale of NRT OTC to adults have not been realized and policymakers should consider reducing barriers to access these products.

Nicotine replacement therapy use among a cohort of smokers.

BACKGROUND: Nicotine replacement therapy (NRT) has been shown to assist smokers to stop smoking in randomized trials, but little is known about its use in the general population. METHODS: As part of ongoing follow-up of a cohort established in 1989 in Washington County, Maryland, a questionnaire mailed in 1998 included a question about ever use of the two NRT products then available over-the-counter: nicotine gum and nicotine patch. This study reports on ever use of NRT among the 1,954 respondents who were current smokers in 1989 and subsequently provided data on NRT use and smoking habits in 1998. RESULTS: Overall, 36% of the smokers in 1989 had ever used NRT in some form by 1998; 10% used gum only, 16% used patch only, and 10% used both gum and patch. Number of cigarettes smoked per day at baseline was the strongest predictor of ever use of NRT (ptrend < 0.001). Compared to nonusers, ever users of NRT were more likely to have more than 12 years of education (p < 0.01) and be 25-54 years old at baseline (p < 0.001). When NRT use was assessed in relation to smoking status in 1998, 30% of NRT ever users compared to 39% of nonusers had quit smoking (p < 0.01). Among persistent smokers, the likelihood of reducing the number of cigarettes smoked per day was similar between NRT ever users (40%) and nonusers (41%). CONCLUSIONS: Ever use of NRT was common among this cohort of smokers, particularly among heavy smokers. Compared to nonusers, ever users of NRT were less likely to have stopped smoking and equally likely to cut down the frequency of smoking. This may reflect a tendency to turn to NRT for help after failing to quit by other means.

Tobacco control policies and the concurrent use of smokeless tobacco and cigarettes among men, 1992-2002.

Accelerating the decline in smoking prevalence requires an understanding of changes in the concurrent use of and the substitution between different tobacco products, such as smokeless tobacco (SLT) and cigarettes. SLT could play an important role in reducing the toll of smoking-related illness and premature mortality. Research examining the role of tobacco control policies in explaining concurrent use of SLT and cigarettes has been minimal. Using the Current Population Survey Tobacco Use Supplements (CPS-TUS), we examined tobacco control policies in relationship with adult males' SLT use concurrent with smoking over the period 1992-2002. Consistent with the decline in smokeless-only and cigarette-only rates, concurrent use of SLT and cigarettes declined during the period. SLT users, faced with home or workplace smoking bans, are less likely to report smoking. Smokers with a home ban appear more likely to use SLT, but in more recent years, smokers with a workplace ban are less likely to use SLT. Tobacco excise taxes do not signal substitution between cigarettes and SLT products. Understanding current use patterns of the range of tobacco products, including their interaction with available policy levers, is vital in assessing whether changes that might promote substitution of arguably less toxic SLT products for highly toxic cigarettes are likely to lead to net public health gains or losses. Findings of the present study, in concert with other research about transitional probabilities between behavioral states, will inform the design of an effective policy framework that supports the objective of reducing tobacco-related death and disease.

Tobacco harm reduction: conceptual structure and nomenclature for analysis and research.

The goal of tobacco control has always been to reduce death and disease due to tobacco use. Recent discussions have broadened the concept of tobacco control beyond cessation and prevention to include concepts such as the use of medications to achieve reduction in tobacco use, chemoprevention to reduce disease, modifications of tobacco products to reduce toxicity, and behavioral approaches to change smoking and tobacco use behavior. Within each of these broad domains, diverse approaches have been suggested. To facilitate clear discussion and analysis, and to avoid confusion among approaches, we catalog 19 approaches to harm reduction, distinguishing and discussing them on 11 dimensions, including their objectives, mechanisms, toxicology, expected population risks, and consumer appeal. Because there have also been so many suggested applications of medicinal nicotine to smoking intervention, we separately catalog and analyze nine applications, some of which constitute new approaches to harm reduction. The suggested framework is intended to clarify the debate, provide for common nomenclature, and facilitate analysis of diverse approaches to tobacco harm reduction.