Respiratory effects of lowering tar and nicotine levels of cigarettes smoked by young male middle tar smokers. II. Results of a randomised controlled trial

Benefits and risks of pharmacological smoking cessation therapies in chronic obstructive pulmonary disease

Smoking cessation is the most effective way to reduce the risk of developing chronic obstructive pulmonary disease (COPD) or to reduce its progression. However, little is known about the efficacy and safety of different pharmacological smoking cessation therapies used for the treatment of patients with COPD who smoke. The aim of this review was to evaluate the benefits and risks of pharmacological smoking cessation therapies in COPD. We conducted an extensive computer-aided literature search which resulted in the identification of four papers that met the inclusion criteria and contributed to this review. In two studies the efficacy of nicotine polacrilex (nicotine gum) was assessed. In one study, which did not have a control group, the efficacy of nicotine nasal spray was evaluated. The fourth study, a placebo-controlled trial, evaluated the efficacy of bupropion sustained release. The results of these studies indicated that nicotine gum, nicotine nasal spray and bupropion have a good safety profile and seem to increase abstinence rates in smokers with COPD. The incidence and nature of specific adverse effects occurring in patients with COPD seem to be comparable with the adverse effects reported by healthy smokers. However, the efficacy seems to depend on the follow-up period used to define success (i.e. abstinence rates decline with longer follow-up), as well as the intensity and duration of the concomitant psychosocial intervention. This review indicates that for a continuation of the effect of pharmacological smoking cessation therapies, the combination of pharmacotherapy (to reduce craving and withdrawal) and a relapse-prevention programme, in which attention is focused on the behavioural aspects of smoking and smoking cessation, seems to increase abstinence, especially when the psychosocial intervention is prolonged for a longer period. Also, the characteristics of the smokers who are motivated to quit must be taken into account in order to increase the number of successful attempts to quit smoking and prevent relapses. We therefore recommend using a holistic approach in which the possible coexistence of multiple problems (which are known to affect the success of smoking cessation strategies) is integrated.

'Smoke like a man, die like a man'?: a review of the relationship between gender, sex and lung cancer

Lung cancer is one of the most important 'avoidable' causes of death world-wide. It is also one in which differences in relation to sex and gender are especially significant. Increasing lung cancer deaths amongst women alongside stable or decreasing deaths amongst men in many countries have substantially altered the male:female ratio in this disease and produced a need to understand differences between men and women in lung cancer risk, and how they relate to sex and gender. This paper reviews research on differences between men and women in lung cancer incidence, mortality and survival, focusing on material which adds to our understanding of the complex differences between each group. This review suggests that the risk of lung cancer may be different for men and women in response to a complex interaction between biological factors such as hormonal difference and gendered factors such as smoking behaviour. In particular women's apparently greater relative risk of lung cancer and the differences between men and women in the risk of specific histological types of lung cancer need to be understood from a perspective in which both biological influences and gender influences are drawn out.

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.

Smoking and chronic obstructive pulmonary disease

Smoking is overwhelmingly the major cause of chronic bronchitis and emphysema worldwide. Additional risk factors for developing COPD are presented, along with the variables that govern cigarette smoke deposition in the lung. Major paradigms for the pathogenesis of COPD, including the protease-antiprotease and oxidant-antioxidant theories are described, and evidence for impaired reparative mechanisms in the causation of emphysema is noted. A description of the natural history of declining lung function in smokers and in the susceptible subset of smokers that ultimately develop smoking-induced COPD is accompanied by a discussion of the effects of smoking cessation on preservation of lung health. The disordered ventilation and gas-exchange physiology in the cigarette smoke-damaged lung is explained on the basis of the observed morphological changes.

The future of tobacco product regulation and labelling in Europe: implications for the forthcoming European Union directive

The European Commission has announced that it is considering legislation concerning further restrictions on cigarette tar and nicotine yields, as well as new provisions to regulate additives and the labelling of tobacco products. This report considers these issues and their relation to public health. In particular, we argue that further reductions in tar and nicotine yields as measured by the International Standards Organisation/Federal Trade Commission (ISO/FTC) method will be largely cosmetic and certainly misleading to consumers. If a new directive uses the ISO/FTC methodology as a basis for regulation, it risks lending further official support to the concept of "low tar" cigarettes, which may be used by smokers as an alternative to smoking cessation. Although new regulations based on the ISO/FTC methodology may appear to offer health gains, these will be illusory and there may even be negative health consequences, as has been the case with these tests up to the present. We therefore make the following recommendations for the way forward.

Changes in cotinine levels during pregnancy

We measured maternal cotinine levels on residual sera of antenatal blood samples to biochemically document changes in smoking between early and late pregnancy. It was a random sample of 404 mothers who had both an early and late sample. Cotinine levels were used to categorize maternal smoking into nonsmoker (<15 ng/mL) and smoker (> or = 15 ng/mL) groups. Designated smokers were further partitioned into lighter (15-100 ng/mL) and heavier (>100 ng/mL) semiquantitative groupings. There was a positive cotinine result in 113 (28%) mothers in early pregnancy; of these smoking women, 35 (31%) had quit smoking by the time of their late pregnancy blood test and 28 (25%) had reduced their cotinine level by at least 25%. Many more lighter smokers had quit (59%) compared to heavier smokers (17%) (X2 = 20.9, df=1, p<0.001). By late pregnancy, 86 (21%) mothers were still defined as smokers. Almost 30% of pregnant women in this sample were smoking during early pregnancy declining to 21% in late pregnancy.

Assessment of simple colorimetric procedures to determine smoking status of diabetic subjects

The performance of a simple colorimetric assay for urinary nicotine metabolites to assess smoking status in diabetic subjects (n = 251) was investigated. Several variations of the colorimetric assay and a qualitative extraction procedure were evaluated in comparison with a cotinine immunoassay as the “gold standard.” Among these, the best overall performance was achieved with the qualitative test (sensitivity 95%; specificity 100%). The quantitative measurement of total nicotine metabolites performed less well (sensitivity 92%; specificity 97%) but could be improved by incorporating a blank extraction (sensitivity 98%; specificity 98%). Allowance for diuresis appeared to offer no advantage over the other methods. These results support previous findings regarding the use of these colorimetric procedures in nondiabetic subjects and, contrary to other recent observations, their performance was not impaired in diabetic patients.

The prevalence of smoking in Austria

BACKGROUND

A population-based cross-sectional study was performed to assess smoking prevalence in Austria and to compare the results with data from 1986.

METHODS

A representative sample of Austrians (n = 2,400) who in 1995 were > or = 15 years of age was obtained. A total of 2,065 respondents were interviewed about their smoking habits.

RESULTS

Approximately 31% of the population age > or = 15 are regular cigarette smokers, 12% are former smokers, 6% smoke occasionally, and 51% have never smoked. Among males, the prevalence of regular smoking increases with age and reaches its highest level between the ages of 25 and 34. The age distribution among female regular smokers shows a similar pattern, peaking in the same age group (35.7% smokers). No significant differences in smoking prevalence were found according to monthly household income, years of school, and number of inhabitants at place of residence. At the time of interview 45.7% of male and 20.9% of female regular smokers consumed > 20 cigarettes per day. Compared with data from 1986 the prevalence of regular smokers increased from 18.1 to 24.2% among females and from 35.5 to 38.9% among males.

CONCLUSIONS

Smoking prevalence increased in Austria between 1986 and 1995 by 33.7% among females and by 9.6% among males. Patterns of smoking among females (prevalence and cigarettes per day) are approaching those of males.

Filter ventilation and nicotine content of tobacco in cigarettes from Canada, the United Kingdom, and the United States

OBJECTIVES

The purpose was to determine filter ventilation and the nicotine content of tobacco and their contribution to machine-smoked yields of cigarettes from the United States, Canada, and the United Kingdom.

METHODS

Ninety-two brands of cigarettes (32 American, 23 Canadian, and 37 British brands) were purchased at retail outlets in State College, Pennsylvania, United States, Toronto, Canada, and London, United Kingdom. A FIDUS FDT filter ventilation tester measured the percentage air-dilution from filter vents. High-pressure, liquid chromatography was used to measure the nicotine content of tobacco. Regression techniques were used to examine the contributions of tobacco nicotine content and filter ventilation to machine-smoked yields of tar, nicotine, and carbon monoxide (CO).

RESULTS

Ninety-four per cent of the American brands, 91% of the Canadian brands, and 79% of British brands were ventilated. The total nicotine content of tobacco and percent nicotine (by weight of tobacco) averaged 10.2 mg (standard error of the mean (SEM) 0.25, range: 7.2 to 13.4) and 1.5% (SEM 0.03, range 1.2 to 2) in the United States, 13.5 mg (SEM 0.49, range: 8.0 to 18.3) and 1.8% (SEM 0.06, range: 1.0 to 2.4) in Canada, 12.5 mg (SEM 0.33, range: 9 to 17.5) and 1.7% (SEM 0.04, range: 1.3 to 2.4) in the United Kingdom. Multiple regression analyses showed that ventilation was by far the largest factor influencing machine-smoked yields of tar, nicotine, and CO.

CONCLUSION

Filter ventilation appears to be the predominant method for reducing machine-smoked yields of tar, nicotine, and CO in three countries. However, some brands contain about twice as much nicotine (total content or percent nicotine) as do others, indicating that tobacco types or blends and tobacco castings can be used to manipulate nicotine content and nicotine delivery of cigarettes.

Smoking during pregnancy: the dose dependence of birthweight deficits

OBJECTIVE

To assess whether a simple urine based estimate of relative daily nicotine intake could predict smoking related birthweight deficits more accurately than self-reported cigarette consumption.

DESIGN

Active smokers were identified by a simple qualitative colorimetric urine test procedure and their relative nicotine intakes assessed by determining the ratios of the urinary concentrations of nicotine plus its metabolites to creatinine using automated colorimetric methods.

SETTING

A large teaching hospital.

PARTICIPANTS

Three thousand and thirty-eight mothers from whom smoking histories had been elicited and who gave birth to live singleton babies after 28 weeks of gestation.

MAIN OUTCOME MEASURES

Birthweights (adjusted for maternal weight, maternal age, baby's sex, parity and length of gestation), maternal weight gains during pregnancy and placental weights.

RESULTS

The adjusted birthweight deficits of babies born to proven active smokers averaged 226 g (95% confidence interval 194 g to 258 g), but dose dependent effects were only apparent when nicotine intake was based on urinary nicotine metabolites/creatinine ratios. Among the smokers, adjusted birthweights fell linearly with increasing nicotine intakes but gave a predicted mean birthweight for nonsmokers that was 102 g (95% CI 50 g to 154 g) lighter than that actually found (P < 0.0001). Maternal weight gains during pregnancy were substantially reduced in smokers and correlated more closely with urinary nicotine metabolite excretions than with reported daily cigarette consumptions. Placental weights were unaffected by smoking.

CONCLUSION

There was a closer dose-effect relationship between birthweight deficits and urinary nicotine metabolites/creatinine ratios than with self-reported daily cigarette consumptions. The influence of nicotine exposure on birthweight appears to be biphasic, with one mechanism operating at very low levels of tobacco smoke intake and the other causing seemingly linearly related effects over the whole range of nicotine intakes of active smokers. These findings support recent evidence that passive smoking can cause substantial birthweight deficits.

Urinary nicotine metabolite excretion and lung cancer risk in a female cohort

A nested lung cancer case-control study was carried out using 397 12 h urine samples originally collected from a cohort of over 26,000 women aged 40-64 at entry who were then followed for up to 15 years. The urine samples from active smokers were first identified using a simple qualitative method and their total nicotine metabolites/creatinine ratios then determined by automated colorimetric methods. The results obtained demonstrated the capacity of nicotine metabolite estimations in a single 12 h sample of urine to predict the subsequent risk of lung cancer. The risk of lung cancer among the biochemically proven active smokers during this period was 7.8 times that of the non-smokers, suggesting that the dose-response relationship between smoking and lung cancer is no less step in women than in men. The smoking-related risk of adenocarcinoma was less than that of other lung carcinomas. It is suggested that this biochemical epidemiology approach to exploring the relationship between smoking and lung cancer could profitably be applied to the study of other smoking-related diseases.