Changes in mortality from smoking in two American Cancer Society prospective studies since 1959

Regulation of endothelial function by cigarette smoke and next-generation tobacco and nicotine products

Cigarette smoking is the most important avoidable cardiovascular risk factor. It causes endothelial dysfunction and atherosclerosis and increases the risk of its severe clinical complications like coronary artery disease, myocardial infarction, stroke, and peripheral artery disease. Several next-generation tobacco and nicotine products have been developed to decrease some of the deleterious effects of regular tobacco smoking. This review article summarizes recent findings about the impact of cigarette smoking and next-generation tobacco and nicotine products on endothelial dysfunction. Both cigarette smoking and next-generation tobacco products lead to impaired endothelial function. Molecular mechanisms of endothelial dysfunction like oxidative stress, reduced nitric oxide availability, inflammation, increased monocyte adhesion, and cytotoxic effects of cigarette smoke and next-generation tobacco and nicotine products are highlighted. The potential impact of short- and long-term exposure to next-generation tobacco and nicotine products on the development of endothelial dysfunction and its clinical implications for cardiovascular diseases are discussed.

Tobacco use disorder and the lungs

This narrative review provides a summary of the impact of tobacco smoking on the respiratory system and the benefits of smoking cessation. Tobacco smoking is one of the leading preventable causes of death world-wide and a major risk factor for lung cancer and chronic obstructive pulmonary disease. Smoking is also associated with an increased risk of respiratory infections and appears to be related to poorer outcomes among those with COVID-19. Non-smokers with second-hand smoke exposure also experience significant adverse respiratory effects. Smoking imposes enormous health- and non-health-related costs to societies. The benefits of smoking cessation, in both prevention and management of respiratory disease, have been known for decades and, to this day, cessation support remains one of the most important cost-effective interventions that health professionals can provide to people who smoke. Cessation at any age confers substantial health benefits, even in smokers with established morbidities. As other treatments for chronic respiratory disease advance and survival rates increase, smoking cessation treatment will become even more relevant. While smoking cessation interventions are available, the offer of these by clinicians and uptake by patients remain limited.

[Bronchial carcinoma and tobacco: An update]

Lung cancer remains the most lethal cancer. The most common cause is smoking, which is also preventable, unlike the causes of other types of cancer. A genetic characteristic has emerged over several years, which explains particular profiles of smokers, or highly dependent smokers. The emergence of new therapies for the treatment of lung cancer, and the impact of tobacco on reducing the effectiveness of these therapies must challenge practitioners to obtain a complete cessation of smoking regardless of the stage of the disease.

Lung cancer mortality in Australia: Projected outcomes to 2040

OBJECTIVES

The aim was to develop and validate a statistical model which uses past trends for lung cancer mortality and historical and current data on tobacco consumption to project lung cancer mortality rates into the future for Australia.

METHODS

We used generalized linear models (GLMs) with Poisson distribution including either age, birth cohort or period, and/or various measures of population tobacco exposure (considering cross-sectional smoking prevalence, cigarettes smoked and tar exposure per capita). Sex-specific models were fitted to data for 1956-2015 and age-standardized lung cancer mortality rates were projected forward to 2040. Possible lags of 20-30 years between tobacco exposure and lung cancer mortality were examined. The best model was selected using analysis of deviance. To validate the selected model, we temporarily re-fitted it to data for 1956-1990 and compared the projected rates to 2015 with the observed rates for 1991-2015.

RESULTS

The best fitting model used information on age, birth cohort and tar exposure per capita; close concordance with the observed data was achieved in the validation. The forward projections for lung cancer mortality using this model indicate that male and female age-standardized rates will decline over the period 2011-2015 to 2036-2040 from 27.2 to 15.1 per 100,000, and 15.8 to 11.8 per 100,000, respectively. However, due to population growth and ageing the number of deaths will increase by 7.9% for males and 57.9% for females; from 41,040 (24,831 males, 16,209 females) in 2011-2015 to 52,403 (26,805 males, 25,598 females) in 2036-2040.

CONCLUSION

In the context of the mature tobacco epidemic with past peaks in tobacco consumption for both males and females, lung cancer mortality rates are expected to continually decline over the next 25 years. However, the number of lung cancer deaths will continue to be substantial, and to increase, in Australia's ageing population.

["Heat not burn" tobacco devices as new tobacco industry products: health risks]

Increased tobacco control measures in recent years have directed the tobacco industry to develop alternative tobacco products, such as "heat not burn" (HnB) tobacco devices that are implied to be less hazardous than conventional cigarettes. There are extensive studies from manufacturers available, which show that the emissions of HnB tobacco devices have significantly lower levels of harmful substances compared to conventional cigarettes. In addition, manufacturers have published studies to investigate whether switching from a conventional tobacco cigarette to the HnB product reduces possible health risks.The purpose of this report is to review current studies by manufacturers and independent institutions as well as to discuss possible reduced health hazards.The German Federal Institute for Risk Assessment (BfR) has carried out its own studies of selected analytes in the emissions of one HnB product confirming the lower levels of harmful substances in the emissions. The results are consistent with data from other independent studies. The nicotine content in the emissions is in the same range as the nicotine emissions of conventional cigarettes, which suggests a comparable addictiveness and dependence potential. Manufacturers have reported mutagenic effects of emissions by HnB tobacco devices that, however, are considerably weaker compared to conventional cigarettes. Nevertheless, the use of the HnB tobacco product remains associated with health risks.Switching from conventional cigarettes to tobacco heaters can significantly reduce the consumer's exposure to harmful substances. However, this article also illustrates that it is still unclear to what extent the reduced levels lead to lowered health risks. Therefore more independent studies, but also long-term studies, are needed.

Cigarette Filter Ventilation and its Relationship to Increasing Rates of Lung Adenocarcinoma

The 2014 Surgeon General's Report on smoking and health concluded that changing cigarette designs have caused an increase in lung adenocarcinomas, implicating cigarette filter ventilation that lowers smoking machine tar yields. The Food and Drug Administration (FDA) now has the authority to regulate cigarette design if doing so would improve public health. To support a potential regulatory action, two weight-of-evidence reviews were applied for causally relating filter ventilation to lung adenocarcinoma. Published scientific literature (3284 citations) and internal tobacco company documents contributed to causation analysis evidence blocks and the identification of research gaps. Filter ventilation was adopted in the mid-1960s and was initially equated with making a cigarette safer. Since then, lung adenocarcinoma rates paradoxically increased relative to other lung cancer subtypes. Filter ventilation 1) alters tobacco combustion, increasing smoke toxicants; 2) allows for elasticity of use so that smokers inhale more smoke to maintain their nicotine intake; and 3) causes a false perception of lower health risk from "lighter" smoke. Seemingly not supportive of a causal relationship is that human exposure biomarker studies indicate no reduction in exposure, but these do not measure exposure in the lung or utilize known biomarkers of harm. Altered puffing and inhalation may make smoke available to lung cells prone to adenocarcinomas. The analysis strongly suggests that filter ventilation has contributed to the rise in lung adenocarcinomas among smokers. Thus, the FDA should consider regulating its use, up to and including a ban. Herein, we propose a research agenda to support such an effort.

Reduction of risk of dying from tobacco-related diseases after quitting smoking in Italy

AIMS AND BACKGROUND

The aims of this paper are to compute the risks of dying of ischemic heart disease (IHD), lung cancer (LC), stroke, and chronic obstructive pulmonary disease (COPD) for Italian smokers by gender, age and daily number of cigarettes smoked, and to estimate the benefit of stopping smoking in terms of risk reduction.

METHODS

Life tables by sex and smoking status were computed for each smoking-related disease based on Italian smoking data, and risk charts with 10-year probabilities of death were computed for never, current and former smokers.

RESULTS

Men aged 45-49 years, current smokers, have a 8, 10, 3 and 1 in 1,000 chance of dying of IHD, LC, stroke and COPD, respectively, whereas women with the same characteristics have a 2, 6, 3 and 1 in 1,000 chance, respectively, for all smokers combined, i.e., independent of the smoking intensity. The risk reduction rates from quitting smoking are remarkable: a man who quits smoking at 45-49 years can reduce the risk of dying of IHD, LC, stroke and COPD in the next 10 years by 43%, 53%, 57% and 55%, respectively; a woman by 49%, 49%, 59% and 57%, respectively.

CONCLUSIONS

Estimates of risk reduction by quitting smoking are useful to provide a sounder scientific basis for public health messages and clinical advice.

Time-varying processes involved in smoking lapse in a randomized trial of smoking cessation therapies

INTRODUCTION

Researchers have increasingly begun to gather ecological momentary assessment (EMA) data on smoking, but new statistical methods are necessary to fully unlock information from such data. In this paper, we use a new technique, the logistic time-varying effect model (logistic TVEM), to examine the odds of smoking in the 2 weeks after a quit attempt.

METHODS

Data are from a subsample of participants from a randomized, placebo-controlled trial of smoking cessation pharmacotherapies who achieved initial abstinence (N = 1,106, 58% female). Participants completed up to 4 EMA assessments per day during the 2 weeks after their quit day. Predictors include baseline nicotine dependence, EMA measures of craving and negative affect, and whether an individual was assigned to a placebo, monotherapy, or combination therapy condition. Time-varying effects of these predictors were estimated using logistic TVEM.

RESULTS

Cravings were a significant predictor of smoking throughout the entire 2 weeks postquit, whereas the effect of baseline dependence became nonsignificant by the second week, and the effect of negative affect increased over time. Individuals in the monotherapy and combination therapy conditions had decreased odds of smoking compared with placebo in the first week postquit, but these differences were nonsignificant in the second week.

CONCLUSIONS

Findings suggest that pharmacotherapies are more effective compared with placebo earlier in a quit attempt, when the effect of baseline nicotine dependence on smoking is stronger, whereas the effect of craving and negative affect increased over time. Future cessation therapies may be more successful by providing additional support in the second week after quit attempt.

Historical Perspectives of the Causation of Lung Cancer: Nursing as a Bystander

Lung cancer is the leading cause of cancer deaths worldwide. Less-known forces are involved in the etiology of lung cancer and have relevant implications for providers in ameliorating care. The purpose of this article is to discuss theories of causation of lung cancer using historical analyses of the evolution of the disease and incorporating related explanations integrating the relationships of science, nursing, medicine, and society. Literature from 160 years was searched and Thagard's model of causation networks was used to exhibit how nursing and medicine were significant influences in lung cancer causation theory. Disease causation interfaces with sociological norms of behavior to form habits and rates of health behavior. Historically, nursing was detrimentally manipulated by the tobacco industry, engaging in harmful smoking behaviors, thus negatively affecting patient care. Understanding the underlying history behind lung cancer causation may empower nurses to play an active role in a patient's health.

Continued increases in the relative risk of death from smoking

OBJECTIVES

We examined changes in the relative risk of death among current and former smokers over recent decades in the United States.

METHODS

Data from the National Health Interview Survey (NHIS) and National Health and Nutrition Examination Survey (NHANES) were linked to subsequent deaths. We calculated age-standardized death rates by gender and smoking status, and estimated multivariate discrete time logit regression models.

RESULTS

The risk of death for a smoker compared with that for a never-smoker increased by 25.4% from 1987 to 2006 based on NHIS data. Analysis of NHANES data from 1971 to 2006 showed an even faster annual increase in the relative risk of death for current smokers. Former smokers also showed an increasing relative risk of death, although the increase was slower than that among current smokers and not always statistically significant. These trends were not related to increasing educational selectivity of smokers or increased smoking intensity or duration among current smokers. Smokers may have become more adversely selected on other health-related variables.

CONCLUSIONS

A continuing increase in the relative risk of death for current and former smokers suggests that the contribution of smoking to national mortality patterns is not decreasing as rapidly as would be implied by the decreasing prevalence of smoking among Americans.

Systematic review with meta-analysis of the epidemiological evidence in the 1900s relating smoking to lung cancer

BACKGROUND

Smoking is a known lung cancer cause, but no detailed quantitative systematic review exists. We summarize evidence for various indices.

METHODS

Papers published before 2000 describing epidemiological studies involving 100+ lung cancer cases were obtained from Medline and other sources. Studies were classified as principal, or subsidiary where cases overlapped with principal studies. Data were extracted on design, exposures, histological types and confounder adjustment. RRs/ORs and 95% CIs were extracted for ever, current and ex smoking of cigarettes, pipes and cigars and indices of cigarette type and dose-response. Meta-analyses and meta-regressions investigated how relationships varied by study and RR characteristics, mainly for outcomes exactly or closely equivalent to all lung cancer, squamous cell carcinoma ("squamous") and adenocarcinoma ("adeno").

RESULTS

287 studies (20 subsidiary) were identified. Although RR estimates were markedly heterogeneous, the meta-analyses demonstrated a relationship of smoking with lung cancer risk, clearly seen for ever smoking (random-effects RR 5.50, CI 5.07-5.96) current smoking (8.43, 7.63-9.31), ex smoking (4.30, 3.93-4.71) and pipe/cigar only smoking (2.92, 2.38-3.57). It was stronger for squamous (current smoking RR 16.91, 13.14-21.76) than adeno (4.21, 3.32-5.34), and evident in both sexes (RRs somewhat higher in males), all continents (RRs highest for North America and lowest for Asia, particularly China), and both study types (RRs higher for prospective studies). Relationships were somewhat stronger in later starting and larger studies. RR estimates were similar in cigarette only and mixed smokers, and similar in smokers of pipes/cigars only, pipes only and cigars only. Exceptionally no increase in adeno risk was seen for pipe/cigar only smokers (0.93, 0.62-1.40). RRs were unrelated to mentholation, and higher for non-filter and handrolled cigarettes. RRs increased with amount smoked, duration, earlier starting age, tar level and fraction smoked and decreased with time quit. Relationships were strongest for small and squamous cell, intermediate for large cell and weakest for adenocarcinoma. Covariate-adjustment little affected RR estimates.

CONCLUSIONS

The association of lung cancer with smoking is strong, evident for all lung cancer types, dose-related and insensitive to covariate-adjustment. This emphasises the causal nature of the relationship. Our results quantify the relationships more precisely than previously.

Chapter 10: A macro-model of smoking and lung cancer: examining aggregate trends in lung cancer rates using the CPS-I and CPS-II and two-stage clonal expansion models

Past studies have examined the relationship of lung cancer to smoking using longitudinal data for select samples. This study applies the two-stage clonal expansion (TSCE) model to U.S. +xsmoking data over a 25-year period. Smoking Base Case (SBC) data on actual smoking duration and intensity from the years 1975-2000 are applied by gender to separate TSCE models, which are then calibrated to historical trends in lung cancer death rates using regression analysis. The uncalibrated and calibrated TSCE models are also applied to SBC data for two scenarios: (1) no tobacco control and (2) complete tobacco control. The results are used to develop estimates of the number of lives saved as a result of tobacco control and how many lives would be saved if cigarette use had ceased in 1965. Predictions of lung cancer from the TSCE models with CPS-II and the CPS-I data for males and especially females are considerably below historical rates with the deviations from historical rates increasing over time. Residual trends unrelated to the smoking models were also found. Tobacco control activities saved approximately 625,000 lives between the years 1975 and 2000. An additional 2,110,000 lives would have been saved if all smoking was stopped in 1965. Tobacco control has successfully prevented lung cancer deaths, but many more lives could be saved with further reductions in smoking rates. Systematic biases were observed from TSCE models using CPS-I and CPS-II data to estimate smoking-related lung cancer deaths.

Chapter 14: Comparing the adequacy of carcinogenesis models in estimating U.S. population rates for lung cancer mortality

The relationship between smoking and lung cancer is well established and cohort studies provide estimates of risk for individual cohorts. While population trends are qualitatively consistent with smoking trends, the rates do not agree well with results from analytical studies. Four carcinogenesis models for the effect of smoking on lung cancer mortality were used to estimate lung cancer mortality rates for U.S. males: two-stage clonal expansion and multistage models using parameters estimated from two Cancer Prevention Studies (CPS I and CPS II). Calibration was essential to adjust for both shift and temporal trend. The age-period-cohort model was used for calibration. Overall, models using parameters derived from CPS I performed best, and the corresponding two-stage clonal expansion model was best overall. However, temporal calibration did significantly improve agreement with the population rates, especially the effect of age and cohort.

Chapter 1:The impact of the reduction in tobacco smoking on U.S. lung cancer mortality, 1975-2000: an introduction to the problem

To better understand the contribution of cigarette smoking, and its changing role in lung cancer, this article provides an introduction to a special issue of Risk Analysis, which considers the relationship between smoking and lung cancer death rates during the period 1975-2000 for U.S. men and women aged 30-84 years. Six models are employed, which are part of a consortium of lung cancer modelers funded by National Cancer Institute's Cancer Intervention and Surveillance Modeling Network (CISNET). Starting with birth-cohort-specific smoking histories derived from National Health Interview Surveys, three scenarios are modeled: Actual Tobacco Control (observed trends in smoking), Complete Tobacco Control (a counterfactual lower bound on smoking rates that could have been achieved had all smoking ceased after the first Surgeon General's report in 1964), and No Tobacco Control (a counterfactual upper bound on smoking rates if smoking patterns that prevailed before the first studies in the 1950s began to inform the public about the hazards of smoking). Using these three scenarios and the lung cancer models, the number and percentage of lung cancer deaths averted from 1975-2000, among all deaths that could have been averted if tobacco control efforts been immediate and perfect, can be estimated. The variability of the results across multiple models provides a measure of the robustness of the results to model assumptions and structure. The results provide not only a portrait of the achieved impact of tobacco control on lung cancer mortality, but also the bounds of what still needs to be achieved.

Has the lung cancer risk from smoking increased over the last fifty years?

BACKGROUND

We examine whether the lung cancer risk due to smoking has increased over time.

METHODS

Lung cancer risk equations based on prospective mortality data collected from 1960 to 1972 were applied to 5-year birth-cohort-specific estimates of smoking behaviors among white males to estimate lung cancer mortality rates for U.S. white males from 1960 to 2000. These estimated rates were compared to U.S. white male mortality rates for the same birth cohorts.

RESULTS

Observed birth-cohort-specific U.S. lung cancer mortality rates are substantially higher than those expected from changes in smoking behaviors, and the proportional difference increases with advancing calendar year. This trend persisted even when the duration term was increased in the risk equation. However, adjusting for changes in cigarette design over time by adding a term for the duration of smoking after 1972 resulted in the predicted rates closely approximating the observed U.S. mortality rates.

CONCLUSION

Lung cancer risk estimates observed during the 1960s under predict current lung cancer mortality rates in U.S. white males. Adjustment for the duration of smoking after 1972 results in estimates that reasonably approximate the observed U.S. lung cancer mortality, suggesting that lung cancer risks from smoking are increasing in the United States coincident with changes in cigarette design.

Do changes in cigarette design influence the rise in adenocarcinoma of the lung?

Background

Incidence rates for adenocarcinoma of the lung are increasing and are higher in the United States than in many other developed countries. We examine whether these trends may be associated with changes in cigarette design.

Methods

Lung cancer risk equations based on observations during 1960–1972 from the American Cancer Society Cancer Prevention Study I are applied to 5-year birth cohort–specific estimates of changes in smoking behaviors to predict birth cohort–specific rates of squamous cell carcinoma and adenocarcinoma of the lung among US White men for the period 1973–2000. These expected rates are compared to observed rates for the same birth cohorts of White men in the US Surveillance, Epidemiology and End Results (SEER) data.

Results

Changes in smoking behaviors over the past several decades adequately explain the changes in squamous cell carcinoma rates observed in the SEER data. However, predicted rates for adenocarcinoma do not match the observed SEER data without inclusion of a term increasing the risk for adenocarcinoma with the duration of smoking after 1965.

Conclusion

The risk of developing squamous cell carcinoma from smoking appears to have remained stable in the United States over the past several decades; however, the risk of adenocarcinoma has increased substantially in a pattern temporally associated with changes in cigarette design.

Evaluating oral noncombustible potential-reduced exposure products for smokers

INTRODUCTION

Potential-reduced exposure products (PREPs) are marketed as a way for smokers to continue using tobacco while possibly lessening their tobacco toxicant intake. Some tobacco-based PREPs are combustible and intended to be smoked, while others are noncombustible and intended to be administered orally (e.g., Camel Snus [CS] tobacco sachets and Ariva tobacco tablets). The ability of these noncombustible PREPs to reduce smokers' exposure to cigarette-delivered toxicants and suppress tobacco abstinence symptoms effectively is unclear. Clinical laboratory methods have been used to measure combustible PREP-associated toxicant exposure and abstinence symptom suppression and could be applied to evaluating the effects of orally administered noncombustible PREPs.

METHODS

In this study, 21 smokers (6 women) participated in four 5-day conditions that differed by product used: CS, Ariva, own brand cigarettes, or no tobacco. Measures included expired-air carbon monoxide (CO), the urinary metabolite of nicotine (cotinine), the urinary metabolite of the carcinogen NNK (NNAL-T), and subjective effect ratings.

RESULTS

Relative to own brand, all other conditions were associated with CO and cotinine levels that were lower and abstinence symptom ratings that were greater. Only no-tobacco use was associated with significantly lower NNAL levels. Acceptability ratings were also lower in all conditions relative to own brand.

DISCUSSION

Although these oral products reduce exposure to CO, their ineffective abstinence symptom suppression and low acceptability may limit their viability as PREPs. As with combustible PREPs, clinical laboratory study of orally administered noncombustible PREPs will be a valuable part of any comprehensive PREP evaluation strategy.

Population-based trends in lung cancer incidence in women

Lung cancer is the leading cause of cancer mortality in women worldwide. Although the rise and growing epidemic status of lung cancer are overwhelmingly attributed to tobacco use, its rank in nonsmokers as the seventh most common cause of cancer worldwide suggests that other factors contribute to this disease. The majority of lung cancers among nonsmokers occur in women. Aside from geographic, cultural, and genetic differences, hormonal and possibly infectious factors also may play etiologic roles. This review aims to discuss the epidemiology of lung cancer in women, as well as the incidence of second primaries, and presents current opinions on the myriad of causes.

Reconciling human smoking behavior and machine smoking patterns: implications for understanding smoking behavior and the impact on laboratory studies

BACKGROUND

Recent Food and Drug Administration legislation enables the mandating of product performance standards for cigarette smoke and the evaluation of manufacturers' health claims for modified tobacco products. Laboratory studies used for these evaluations and also for understanding tobacco smoke toxicology use machines to generate smoke. The goal of this review is to critically evaluate methods to assess human smoking behavior and replicate this in the laboratory.

METHODS

Smoking behavior and smoking machine studies were identified using PubMed and publicly available databases for internal tobacco company documents.

RESULTS

The smoking machine was developed to generate smoke to allow for comparing cigarette tar and nicotine yields. The intent was to infer relative human disease risk, but this concept was flawed because humans tailor their smoking to the product, and chemical yields and toxicologic effects change with different smoking profiles. Although smoking machines also allow for mechanistic assessments of smoking-related diseases, the interpretations also are limited. However, available methods to assess how humans puff could be used to provide better laboratory assessments, but these need to be validated. Separately, the contribution of smoke mouth-holding and inhalation to dose need to be assessed, because these parts of smoking are not captured by the smoking machine. Better comparisons of cigarettes might be done by tailoring human puff profiles to the product based on human studies and comparing results across regimens.

CONCLUSIONS

There are major research gaps that limit the use of smoking machine studies for informing tobacco control regulation and mechanistic studies.

Smoking trajectories, health, and mortality across the adult lifespan

This study extends research on the association between smoking behavior and chronic disease by following a cohort from the time of initiation of regular smoking patterns into old age and by examining the association of lifetime smoking trajectories with chronic disease and mortality. Participants consisted of 232 males selected from the Harvard classes of 1942-1944 and followed biennially through 2003. Five distinct smoking trajectories were identified based on the age at which participants quit daily smoking. Participants following smoking trajectories with later cessation had a higher likelihood of developing lung disease and lived shorter lives than those who quit smoking at an earlier age. This study confirms that the earlier a smoker quits, the greater the health benefits, and that these benefits are observed even decades after smoking cessation. Additionally, by showing different survival rates between trajectory groups 25 and 40 years after quitting, the results run counter to previous work that has found no difference in mortality between smokers and non-smokers 15 years after cessation.

Male tobacco smoke load and non-lung cancer mortality associations in Massachusetts

Background

Different methods exist to estimate smoking attributable cancer mortality rates (Peto and Ezzati methods, as examples). However, the smoking attributable estimates using these methods cannot be generalized to all population sub-groups. A simpler method has recently been developed that can be adapted and applied to different population sub-groups. This study assessed cumulative tobacco smoke damage (smoke load)/non-lung cancer mortality associations across time from 1979 to 2003 among all Massachusetts males and ages 30–74 years, using this novel methodology.

Methods

Annual lung cancer death rates were used as smoke load bio-indices, and age-adjusted lung/all other (non-lung) cancer death rates were analyzed with linear regression approach. Non-lung cancer death rates include all cancer deaths excluding lung. Smoking-attributable-fractions (SAFs) for the latest period (year 2003) were estimated as: 1-(estimated unexposed cancer death rate/observed rate).

Results

Male lung and non-lung cancer death rates have declined steadily since 1992. Lung and non-lung cancer death rates were tightly and steeply associated across years. The slopes of the associations analyzed were 1.69 (95% confidence interval (CI) 1.35–2.04, r = 0.90), and 1.36 (CI 1.14–1.58, r = 0.94) without detected autocorrelation (Durbin-Watson statistic = 1.8). The lung/non-lung cancer death rate associations suggest that all-sites cancer death rate SAFs in year 2003 were 73% (Sensitivity Range [SR] 61–82%) for all ages and 74% (SR 61–82%) for ages 30–74 years.

Conclusion

The strong lung/non-lung cancer death rate associations suggest that tobacco smoke load may be responsible for most prematurely fatal cancers at both lung and non-lung sites. The present method estimates are greater than the earlier estimates. Therefore, tobacco control may reduce cancer death rates more than previously noted.

Smoke load/cancer death rate associations in Korea females, 1985-2004

BACKGROUND

Korea female death rates from many cancers have risen rapidly since 1985. The sources of those cancer death epidemics are unclear but may be related to rising cumulative tobacco smoke damage (smoke load). We assessed Korea female smoke load/cancer death rate associations from 1985 to 2004.

METHODS

Lung cancer rates were used as a smoke load bio-index. Subtracting lung, stomach, and uterine corpus cancer death World age standard rates (rates) from all-sites rates gave us non-lung-stomach-uterine corpus (NLSUc) rates. Lung/NLSUc linear regressions were run, adjusted for autocorrelation. Estimated, lower, and upper bound smoking-attributable fractions (SAFs) were calculated using the formula SAF=1-{(unexposeds' cancer death rate)/(observed rate)}, based on the linear regression and respective best, upper, and lower bound estimated lung, stomach, and uterine cancer death rates in the unexposed.

RESULTS

Lung cancer death rates (smoke load) can explain 88% of the variance in NLSUc rates from 1985 to 2004 after adjusting for autocorrelation. The estimated Korea female all-sites cancer death rate SAF in 2004 was 43% (sensitivity range 29-56%).

CONCLUSIONS

Smoke load, probably from tobacco given the epidemic time course, may cause a large cancer death burden in Korea females despite their very low self-reported prevalence of smoking.

Relationship of human toenail nicotine, cotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol to levels of these biomarkers in plasma and urine

Recently, we developed sensitive and quantitative methods for analysis of the biomarkers of tobacco smoke exposure nicotine, cotinine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) in human toenails. In this study, we further evaluated the newly developed toenail biomarkers by investigating their relationship to demographic factors, reported exposure, plasma nicotine, cotinine, and trans-3'-hydroxycotinine, and urinary NNAL. Toenails of 105 smokers, mean age 38.9 years (range, 19-68), were analyzed. Fifty-five (53.4%) were male, with approximately equal numbers of Whites and African-Americans. The average number of cigarettes smoked per day was 18 (range, 5-50). There was no effect of age or gender on the toenail biomarkers. Toenail NNAL was higher in White than in African-American participants (P = 0.019). Toenail nicotine and toenail cotinine correlated significantly with cigarettes smoked per day (r = 0.24; P = 0.015 and r = 0.26; P = 0.009, respectively). Toenail nicotine correlated with plasma nicotine (r = 0.39; P < 0.001); toenail cotinine correlated with plasma cotinine (r = 0.45; P < 0.001) and plasma trans-3'-hydroxycotinine (r = 0.30; P = 0.008); and toenail NNAL correlated with urine NNAL (r = 0.53; P = 0.005). The results of this study provide essential validation data for the use of toenail biomarkers in investigations of the role of chronic tobacco smoke exposure in human cancer.

Clinical laboratory evaluation of potential reduced exposure products for smokers

Smoking-related cancer and other disease account for more than 400,000 U.S. deaths annually. Smoking cessation reduces smoking-related disease rates, but relapse rates are high. Thus, interest in reducing the harm of continued smoking is growing. Potential reduced exposure products (PREPs) are marketed to reduce smokers' exposure to smoke toxicants such as carbon monoxide (CO) and carcinogens and may be harm reduction tools. New PREPs are proliferating, but past experience with "low-yield" cigarettes that failed to reduce smokers' toxicant exposure suggests that comprehensive evaluation is necessary to predict if these new products are likely to alter the harm caused by smoking. The purpose of the study was to develop clinical laboratory methods for PREP evaluation. Smokers (N = 35) completed four, 5-day conditions that differed by product used: Advance, Eclipse, own brand cigarettes, or no cigarettes. Carcinogen (as assessed by one nitrosamine and one polycyclic aromatic hydrocarbon biomarker) and nicotine exposure were assessed via thrice-weekly urine sampling. Withdrawal symptoms were measured daily, and smoking behavior was assessed on the first and last day of each condition. Relative to own brand, Advance reduced exposure to the nitrosamine NNK and CO, and Eclipse reduced exposure to nicotine and the nitrosamine NNK, increased exposure to CO, and resulted in larger, longer, and more frequent puffs. No smoking reduced exposure to the nitrosamine NNK, CO, and nicotine, whereas withdrawal was elevated (all p values <.05). Clinical laboratory evaluation of PREPs for smokers is valuable for measuring users' smoke toxicant exposure, withdrawal, and smoking behavior and should be incorporated into a comprehensive PREP evaluation strategy.

The consequences of the unregulated cigarette

This article considers changes in cigarette design in relation to the concept of "dose", drawing attention to the observation that there is not one smoking related epidemic of lung cancer, but at least two. Squamous carcinoma is declining in parallel with smoking prevalence while adenocarcinoma is increasing in the face of declining smoking prevalence. It is concluded that the adenocarcinoma epidemic is unnecessary and is due substantially to cigarette design changes, including increases in tobacco specific nitrosamines, manipulation of droplet size and ventilated filters. The need for regulation of smoke constituents is emphasised.

Tobacco smoke overload and ethnic, state, gender, and temporal cancer mortality disparities in Asian-Americans and Pacific Islander-Americans

BACKGROUND

Asians and Pacific Islanders (APIs) are important populations nationally and globally. So we assessed cumulative tobacco smoke overexposure (smoke overload)/cancer mortality associations across states, ethnicities, years, and genders among API-Americans.

METHODS

Death rates were adjusted to the 2000 United States age standard, lung cancer death rates used as a smoke overload bio-index, and lung/non-lung cancer death rate linear regressions run. Cancer death rate smoking-attributable fractions (SAFs) are equal to 1--estimated unexposed rate/observed rate.

RESULTS

The two lowest smoke overload and non-lung cancer death rates were in South Asian (Indo)-Californian females and males. The highest were in Korean-Californian males. Non-lung cancer death rates were tightly and steeply associated with smoke overload across ethnicity, state, year, or gender. Cancer death rate smoking-attributable fractions ranged from 0 in female and 6% in male Indo-Californians, to 39% in female and 57% in male API-Americans in 2002, to 71% in Korean-Californian and 69% in API Hawaiian males.

DISCUSSION

Many API American cancer death rate disparities across genders, ethnicities, states, or years can be explained by smoke overload disparities. Tobacco control may greatly reduce cancer death rates and disparities among API-Americans and, likely, others.

Do reductions in the tar and nicotine yields of cigarettes help to explain recent reductions in lung cancer rates in young men and women in the United States?

Between 1985 and 2000, lung cancer rates in U.S. men and women aged 35-54 yr have declined. To investigate whether these declines can adequately be explained by changes in smoking prevalence, consumption, and duration, or if changes in tar and nicotine yields also contributed, two model-fitting approaches were used. Both approaches used individual person National Health Interview Survey data on smoking prevalence, age of starting and time of quitting, and national estimates of consumption per smoker and yields. Both approaches compared observed rates (by sex and age) relative to 1985, with those predicted after successively including various smoking variables into the model, making varying allowance for compensation for reduced yield. Approach A was simpler, based on mean smoking statistics estimated separately for current and former smokers. Approach B used the multistage model and individual smoking histories to estimate risk. Both approaches showed observed declines in risk were (except for men aged 35-39 yr) clearly greater than predicted based only on prevalence, consumption, and duration. Including yield generally improved the fit. At younger ages, models assuming substantial compensation (consistent with evidence from studies relating nicotine yield and intake) fitted well, but at age 50-54 yr in both sexes and age 45-49 yr in women, the decline was better fitted by models assuming little compensation. The conclusions were not sensitive to the precise parameter values assumed in the modeling. Interpretation is not straightforward, but the findings suggest declines in yields have contributed to the recent declines in rates in young U.S. men and women.

The influence of gender, race, and menthol content on tobacco exposure measures

Research has suggested that race, gender, and menthol cigarette use influence tobacco-smoke exposure measures and smoking-related disease risk. For example, a high proportion of Black smokers prefer menthol cigarettes and, despite smoking fewer cigarettes per day (CPD) than do Whites, tend to have higher cotinine levels. Additionally, Black males are more at risk for smoking-related lung cancer. High cotinine levels and smoking menthol cigarettes may lead to higher toxin intake, which contributes to increased disease risk. We explored the relationship between tobacco exposure variables (i.e., cotinine, CPD, carbon monoxide [CO], nicotine content, and nicotine dependence) with respect to race, gender, and menthol content in a sample of 307 smokers recruited from the greater Boston area to participate in a smoking cessation treatment trial. The pattern of correlations between tobacco exposure measures and cotinine showed a consistently positive correlation between cotinine and CO in all smokers and a correlation between cotinine and CPD in those who smoked nonmenthol cigarettes. Cotinine and CPD correlations varied by gender and race among menthol cigarette smokers. Consistently, we found a significant gender x race x menthol interaction on salivary cotinine level as well as cotinine/CPD ratio. These findings suggest that the relationship between number of cigarettes consumed and salivary cotinine is more complex than previously believed. It is not sufficient to look at race alone; researchers and clinicians need to look at race and gender concurrently, as well as type of cigarette consumed.

Methods to assess potential reduced exposure products

The availability of tobacco products purported to reduce toxin exposure or potentially reduce health risks necessitates the development of methods and identification of biomarkers that can be used to assess these products. These assessments occur on multiple levels and stages, from identifying constituents in the tobacco products and smoke, to human exposure and health effects trials, to postmarketing surveillance. A conference of multidisciplinary experts was convened to present and discuss methods and biomarkers to assess these products and to consider the infrastructure necessary to facilitate the evaluation process. Although no currently available set of measures was thought to be sufficient for determining the relative health risk of potential reduced exposure products, this paper provides a blueprint for future research toward this end.

Cancer death epidemics in United States Black males: evaluating courses, causation, and cures

BACKGROUND

Estimates that smoking contributes 38-72% of the United States (US) Black male cancer death rate leave a wide range of uncertainty. This paper uses additional and regional data, and refined methods, to reassess that range.

METHODS

This study uses lung cancer rates as an exposure index, linear regression, age adjusted US 1950-2001 and US regional 1969-2001 death rates (rates), and the formula: smoking-attributable fraction (SAF)=(1-((rate in the unexposed) / (rate in the exposed))). Estimated lung cancer rates in the unexposed range between rates predicted for a population with no smoking-attributable lung cancers to rates seen in "nonsmokers."

RESULTS

Lung cancer death rates predicted 99.9% and 99.8% of the variances in non-lung non-stomach cancer death rates from 1950-1980 and 1950-1988, respectively (each P<0.0001). That suggests 2001 all-sites cancer death SAFs of 63% (sensitivity range 60-66%) nationally and from 43% in the Northeast to 67% in the South.

CONCLUSIONS

Smoking may cause most premature cancer deaths and temporal and regional cancer death rate disparities in Black men.

Does increased cigarette consumption nullify any reduction in lung cancer risk associated with low-tar filter cigarettes?

Epidemiological data suggest that smoking filter and lower tar cigarettes is associated with less lung cancer risk than is smoking plain and higher tar cigarettes. A recent National Cancer Institute monograph claimed these apparent benefits of lower delivery products may be illusory if relative risks are adjusted for daily consumption, and switching leads to "compensation" for reduced nicotine intake by increasing numbers of cigarettes smoked. To investigate this, we compared relative risks unadjusted and adjusted for daily cigarette consumption. Overall estimates of the filter/plain relative risk, using random-effects meta-analysis, were 0.61 (95%confidence interval 0.54 to 0.70) for unadjusted data and 0.66 (0.58 to 0.76) for adjusted data. The lower tar/higher tar relative risk was estimated as 0.60 (0.45 to 0.81) for unadjusted data and 0.73 (0.64 to 0.83) for adjusted data. The risk reductions were clearly seen regardless of gender, study location, period, or design, and when only studies providing both unadjusted and adjusted estimates were considered. Whether or not relative risk estimates are adjusted for cigarette consumption is not crucial to the conclusion of a clear advantage to filter cigarettes and tar reduction. Data on "compensation" for amount smoked were reviewed and any increase following switching to reduced-tar-yield cigarettes was shown to be quite small. Other biases in the epidemiology are also discussed, and we conclude that the apparent advantage to reduced-tar-delivery products is real and likely to be a marked underestimate of the reduction in lung cancer risk from lifetime smoking of low-tar cigarettes.

Cigarette tar yields in relation to mortality from lung cancer in the cancer prevention study II prospective cohort, 1982-8

OBJECTIVE

To assess the risk of lung cancer in smokers of medium tar filter cigarettes compared with smokers of low tar and very low tar filter cigarettes.

DESIGN

Analysis of the association between the tar rating of the brand of cigarette smoked in 1982 and mortality from lung cancer over the next six years. Multivariate proportional hazards analyses used to assess hazard ratios, with adjustment for age at enrollment, race, educational level, marital status, blue collar employment, occupational exposure to asbestos, intake of vegetables, citrus fruits, and vitamins, and, in analyses of current and former smokers, for age when they started to smoke and number of cigarettes smoked per day.

SETTING

Cancer prevention study II (CPS-II).

PARTICIPANTS

364 239 men and 576 535 women, aged > or = 30 years, who had either never smoked, were former smokers, or were currently smoking a specific brand of cigarette when they were enrolled in the cancer prevention study.

MAIN OUTCOME MEASURE

Death from primary cancer of the lung among participants who had never smoked, former smokers, smokers of very low tar (< or = 7 mg tar/cigarette) filter, low tar (8-14 mg) filter, high tar (> or = 22 mg) non-filter brands and medium tar conventional filter brands (15-21 mg).

RESULTS

Irrespective of the tar level of their current brand, all current smokers had a far greater risk of lung cancer than people who had stopped smoking or had never smoked. Compared with smokers of medium tar (15-21 mg) filter cigarettes, risk was higher among men and women who smoked high tar (> or = 22 mg) non-filter brands (hazard ratio 1.44, 95% confidence interval 1.20 to 1.73, and 1.64, 1.26 to 2.15, respectively). There was no difference in risk among men who smoked brands rated as very low tar (1.17, 0.95 to 1.45) or low tar (1.02, 0.90 to 1.16) compared with those who smoked medium tar brands. The same was seen for women (0.98, 0.80 to 1.21, and 0.95, 0.82 to 1.11, respectively).

CONCLUSION

The increase in lung cancer risk is similar in people who smoke medium tar cigarettes (15-21 mg), low tar cigarettes (8-14 mg), or very low tar cigarettes (< or = 7 mg). Men and women who smoke non-filtered cigarettes with tar ratings > or = 22 mg have an even higher risk of lung cancer.

Treatment of adolescent tobacco smokers: issues and opportunities for exposure reduction approaches

The cycle of tobacco dependence typically begins with the initiation of tobacco use during adolescence. Many teenagers try to quit smoking, fail and subsequently desire treatment for their tobacco dependence. Adolescents do not currently benefit from the same level of societal support for quit attempts as adults, and they may be less motivated for total cessation despite the short and long-term health consequences of smoking. Overall, the combination of low participation, high attrition and low complete cessation rates for adolescent smokers in treatment prompts the consideration of alternative treatment endpoints. It is likely that interactions among the processes of child and adolescent development, smoke exposure and trajectory influence patterns of tobacco use and treatment for tobacco dependence in adolescents. A rational framework is needed to integrate the study of these dynamic interactions to address tobacco dependence among youth from an exposure reduction, in addition to a cessation, perspective. This paper considers the issues and potential implications of tobacco exposure reduction therapy as an intermediate treatment goal for adolescent smokers who are dependent or dependence-prone, but for whom initial treatment interventions do not yield complete tobacco cessation.

Benefits of smoking cessation for longevity

OBJECTIVES

This study determined the life extension obtained from stopping smoking at various ages.

METHODS

We estimated the relation between smoking and mortality among 877,243 respondents to the Cancer Prevention Study II. These estimates were applied to the 1990 US census population to examine the longevity benefits of smoking cessation.

RESULTS

Life expectancy among smokers who quit at age 35 exceeded that of continuing smokers by 6.9 to 8.5 years for men and 6.1 to 7.7 years for women. Smokers who quit at younger ages realized greater life extensions. However, even those who quit much later in life gained some benefits: among smokers who quit at age 65 years, men gained 1.4 to 2.0 years of life, and women gained 2.7 to 3.7 years.

CONCLUSIONS

Stopping smoking as early as possible is important, but cessation at any age provides meaningful life extensions.

The American Cancer Society Cancer Prevention Study II Nutrition Cohort: rationale, study design, and baseline characteristics

BACKGROUND

Large-scale, prospective cohort studies have played a critical role in discovering factors that contribute to variability in cancer risk in human populations. Epidemiologists and volunteers at the American Cancer Society (ACS) were among the first to establish such cohorts, beginning in the early 1950s and continuing through the present, and these ACS cohorts have made landmark contributions in many areas of epidemiologic research.

METHODS AND RESULTS

The Cancer Prevention Study II Nutrition Cohort was established in 1992 and was designed to investigate the relation between diet and other lifestyle factors and exposures and the risk of cancer, mortality, and survival. The cohort includes over 84,000 men and 97,000 women who completed a mailed questionnaire in 1992. New questionnaires are sent to surviving cohort members every other year to update exposure information and to ascertain new occurrences of cancer; a 90% response rate was achieved for follow-up questionnaires in 1997 and 1999. Reported cancers are verified through medical records, registry linkage, or death certificates. The cohort is followed actively for all cases of incident cancer and for all causes of death. Through a collaborative effort among ACS national and division staff, volunteers, and the American College of Surgeons, blood samples were collected from a subgroup of 40,000 cohort members and are in storage at a central repository for future investigation of dietary, hormonal, genetic, and other factors and cancer risk. Collection of DNA samples from buccal cells in an additional 50,000 cohort members is underway currently and will be completed in 2002.

CONCLUSIONS

This new cohort of both men and women promises to be particularly valuable for the study of cancer occurrence, mortality, and survival as they relate to obesity and weight change, physical activity at various points in life, vitamin supplement use, exogenous hormone use, other medications (such as aspirin and nonsteroidal anti- inflammatory drugs) and cancer screening modalities.

A longitudinal study of the effects of tobacco smoking and other modifiable risk factors on ill health in middle-aged and old Americans: results from the Health and Retirement Study and Asset and Health Dynamics among the Oldest Old survey

BACKGROUND

While the effects of smoking and other modifiable risk factors on mortality and specific diseases are well established, their effects on ill health more generally are less known. Using two national, longitudinal surveys, the objective of this study was to analyze the effect of smoking and other modifiable risk factors on ill health, defined in a multidimensional fashion (i.e., disability, impaired mobility, health care utilization, and self-reported health).

METHODS

The analyses were based on the Health and Retirement Study (HRS) (12,652 persons 50-60 years old surveyed in 1992, 1994, 1996, and 1998) and the Asset and Health Dynamics among the Oldest Old survey (8,124 persons 60-70 years old surveyed in 1993, 1996, and 1998).

RESULTS

Smoking was strongly related to mortality and to ill health, with similar relative effects in the middle-aged and the elderly. There were consistent adverse dose-response relationships between smoking and ill health in the HRS. Persons who had quit smoking at least 15 years prior to the survey were no more likely than never smokers to experience ill health. A dose-response relationship was found between exercise and ill health. For body mass index and alcohol, there were U-shaped relationships with ill health.

CONCLUSIONS

Public health efforts designed to encourage smoking cessation should emphasize improvements in ill health in addition to decreased mortality.

The American Cancer Society Cancer Prevention Study II Nutrition Cohort: rationale, study design, and baseline characteristics

BACKGROUND

Large-scale, prospective cohort studies have played a critical role in discovering factors that contribute to variability in cancer risk in human populations. Epidemiologists and volunteers at the American Cancer Society (ACS) were among the first to establish such cohorts, beginning in the early 1950s and continuing through the present, and these ACS cohorts have made landmark contributions in many areas of epidemiologic research.

METHODS AND RESULTS

The Cancer Prevention Study II Nutrition Cohort was established in 1992 and was designed to investigate the relation between diet and other lifestyle factors and exposures and the risk of cancer, mortality, and survival. The cohort includes over 84,000 men and 97,000 women who completed a mailed questionnaire in 1992. New questionnaires are sent to surviving cohort members every other year to update exposure information and to ascertain new occurrences of cancer; a 90% response rate was achieved for follow-up questionnaires in 1997 and 1999. Reported cancers are verified through medical records, registry linkage, or death certificates. The cohort is followed actively for all cases of incident cancer and for all causes of death. Through a collaborative effort among ACS national and division staff, volunteers, and the American College of Surgeons, blood samples were collected from a subgroup of 40,000 cohort members and are in storage at a central repository for future investigation of dietary, hormonal, genetic, and other factors and cancer risk. Collection of DNA samples from buccal cells in an additional 50,000 cohort members is underway currently and will be completed in 2002.

CONCLUSIONS

This new cohort of both men and women promises to be particularly valuable for the study of cancer occurrence, mortality, and survival as they relate to obesity and weight change, physical activity at various points in life, vitamin supplement use, exogenous hormone use, other medications (such as aspirin and nonsteroidal anti-inflammatory drugs) and cancer screening modalities.

Lung cancer mortality rates in birth cohorts in the United States from 1960 to 1994

We sought to describe the changing death rates from lung cancer in the US white population in sequential birth cohorts, adjusting for cohort smoking prevalence and duration. We searched the US mortality database (1960-1994) for all deaths among whites in which lung cancer was listed as the underlying cause of death. To determine the population at risk for lung cancer, we used the 1970, 1978-1980, and 1992 National Health Interview Surveys to estimate the annual number of current and recent smokers (those who had quit within 5 years) in 11 5-year birth cohorts, starting in 1901. We then determined annual lung cancer mortality rates for each birth cohort, stratified by sex and adjusting for the prevalence and duration of smoking. The population-based rates of lung cancer mortality were much higher among men than among women across all ages and birth cohorts, reflecting higher smoking rates among men. These differences decreased after we controlled for current and recent smoking within the cohorts and were slightly increased in women after we controlled for duration of smoking. Differences in lung cancer death rates across birth cohorts of US men and women primarily reflect differences in the prevalence and duration of smoking in these birth cohorts. Changes in cigarette design that have greatly reduced tar yields have a relatively small effect compared with that of people's smoking status and duration of smoking.

Health impact of "reduced yield" cigarettes: a critical assessment of the epidemiological evidence

Cigarettes with lower machine measured "tar" and nicotine yields have been marketed as "safer" than high tar products over the last four decades, but there is conflicting evidence about the impact of these products on the disease burden caused by smoking. This paper critically examines the epidemiological evidence relevant to the health consequences of "reduced yield" cigarettes. Some epidemiological studies have found attenuated risk of lung cancer but not other diseases, among people who smoke "reduced yield" cigarettes compared to smokers of unfiltered, high yield products. These studies probably overestimate the magnitude of any association with lung cancer by over adjusting for the number of cigarettes smoked per day (one aspect of compensatory smoking), and by not fully considering other differences between smokers of "high yield" and "low yield" cigarettes. Selected cohort studies in the USA and UK show that lung cancer risk continued to increase among older smokers from the 1950s to the 1980s, despite the widespread adoption of lower yield cigarettes. The change to filter tip products did not prevent a progressive increase in lung cancer risk among male smokers who began smoking during and after the second world war compared to the first world war era smokers. National trends in vital statistics data show declining lung cancer death rates in young adults, especially males, in many countries, but the extent to which this is attributable to "reduced yield" cigarettes remains unclear. No studies have adequately assessed whether health claims used to market "reduced yield" cigarettes delay cessation among smokers who might otherwise quit, or increase initiation among non-smokers. There is no convincing evidence that past changes in cigarette design have resulted in an important health benefit to either smokers or the whole population. Tobacco control policies should not allow changes in cigarette design to subvert or distract from interventions proven to reduce the prevalence, intensity, and duration of smoking.