Does switching from cigarettes to pipes or cigars reduce tobacco smoke exposure?

Cigarette smoking histories, reported depth of inhalation, number of pipe and cigars (PC) smoked, serum thiocyanate (SCN) and expired air carbon monoxide (CO) levels were examined in PC male smokers enrolled in the Multiple Risk Factor Intervention Trial (MRFIT). Serum SCN levels for all PC smokers were higher than for non-smokers and lower than for current cigarette smokers. Levels were related to the amount of product smoke. Prior cigarette smokers had higher SCN levels when compared to PC users who had never smoked cigarettes, smoked a larger number of tobacco products per day, and reported inhaling into the chest more often. Prospective data on baseline cigarette smokers demonstrated that smokers who stopped all tobacco products had a greater drop in SCN and CO than those who switched to PC. The findings strongly suggest that cessation of all tobacco products is the best strategy for decreasing exposure to tobacco smoke.     

Smoking habits and blood carbon monoxide levels

The carboxyhemoglobin concentrations (COHb) of 97 meat porters, 77 office workers, and 200 pregnant women have been determined. Individuals were questioned on smoking habits including numbers normally smoked per day, numbers already smoked on day of sampling, and time since last cigarette. The number of cigarettes smoked per day appears to allow the best prediction of COHb concentration. Individuals whose occupation involved them in physical exertion (meat porters) accumulated less carbon monoxide (CO) for numbers of cigarettes smoked per day than individuals smoking whilst sedentary. Pregnant women were seen to accumulate CO in a similar way to the active meat porters. In all groups, smokers had significantly higher COHb concentrations than nonsmokers. The effects of activity on CO uptake and elimination are discussed in relation to cigarette smoking, and it is suggested that the effect of activity on COHb is related more to elimination in the nonsmoking periods rather than uptake in the smoking periods.     

Smoking cessation program: baseline carbon monoxide and serum thiocyanate levels as predictors of outcome

One hundred and sixty-two smokers who participated in an aggressive smoking cessation program underwent analysis of expired air carbon monoxide (CO) and serum thiocyanate (SCN) at entry and one year later. Persons who failed to quit smoking had higher baseline CO and SCN and smoked more cigarettes per day than did those who succeeded in quitting. The use of CO, SCN, number of cigarettes smoked, age, and blood pressure at baseline permitted accurate classification of over 70 per cent of the subjects into groups which would succeed and fail in their effort to quit smoking. Persons who failed to quit reduced the reported number of cigaretts smoked per day by one-third, but there was no corresponding reduction in CO and SCN, suggesting that self-reporting of a reduction in the number of cigarettes smoked may not lead to a corresponding decline in exposure.     

Health behaviors, risk factors, and health indicators associated with cigarette use in Mexican Americans: results from the Hispanic HANES.

BACKGROUND: Cigarette smokers often engage in other, potentially deleterious, health behaviors. Such behaviors have not been well documented in Mexican American smokers. METHODS: Data from the Southwestern sample of the Hispanic Health and Nutrition Examination Survey (HHANES) were employed to investigate differences in health behaviors, risk factors and health indicators between cigarette smokers and nonsmokers among Mexican Americans. Differences between those smoking less than 10 and 10 or more cigarettes per day were also examined by age group and gender. RESULTS: Positive associations between smoking status and heavy coffee and alcohol consumption were found across gender and age groups. Less consistent was the finding that smokers weighed less than nonsmokers. Lower systolic and diastolic blood pressures in middle-aged smokers, and higher levels of depressive symptomatology among smoking women were found. Those smoking 10 or more cigarettes per day were more likely to report heavy coffee consumption, with younger men reporting greater activity limitation due to poor health. Middle-aged men and women in the 10+ category were generally in better health than lighter smokers. CONCLUSIONS: Modest associations between cigarette smoking, health behaviors and risk factors found in other studies were confirmed in this Mexican American population. Few significant associations between smoking and health status were noted.     

Smoking and life expectancy among U.S. veterans.

Life expectancies were estimated for selected groups of smokers, ex-smokers, and nonsmokers based on the results of a 16-year mortality follow-up of 198,820 U.S. veterans. Life expectancy varied inversely with number of cigarettes smoked per day. The most pronounced differences were between nonsmokers and heavy cigarette smokers (40+ per day). These differences in life expectancy were greatest at the younger ages--nearly 9 years at ages 35 and 40. Life expectancies for cigarette smokers varied directly with age began smoking. For all ages, differences in life expectancy between nonsmokers and ex-cigarette smokers who stopped for other than doctor's orders were less than those between nonsmokers and current cigarette smokers. Results in the present study clearly confirmed Hammond's earlier findings.     

Cigarette smoking and coronary heart disease in Puerto Rico

Cigarette smoking habits were assessed in over 9000 men, aged 45–64 years, who participated in a prospective study of coronary heart disease (CHD) in Puerto Rico beginning in 1965. Fewer Puerto Rican men smoked cigarettes, and they smoked fewer cigarettes per day than in comparable studies in the mainland United States. Even in this lower-smoking, low-CHD population, cigarette smoking showed a significant independent association with the incidence of myocardial infarction (MI) over an 8-year period both in the rural and urban areas; however, this association was not statistically significant for other manifestations of CHD. Pipe and cigar smokers had a risk of MI similar to nonsmokers. Those men who used filter cigarettes or who stated that they did not inhale showed the same risk of MI as other cigarette smokers. Ex-smokers had a risk of MI intermediate to that of nonsmokers and current smokers. The risk of MI did not increase with an increase in the number of cigarettes smoked, but the risk of MI in smokers as a group relative to those who had never smoked was 3.4 in the rural area and 2.0 in the urban area. These results emphasize that there is an excess risk of MI in those cigarette smokers who report that they used filter cigarettes, did not inhale, or smoked a small number of cigarettes a day.     

Infant birth weight as a measure of harm reduction during smoking cessation trials in pregnancy.

During pregnancy, a reduction of 50% or more of a biochemical measure of smoking, among continuing smokers, has been proposed by Windsor and colleagues as a new behavioral indicator of harm reduction because it was accompanied by greater infant birth weight compared with that of infants of smokers with lesser reductions. The purpose of the authors' study was to replicate these observations. During a trial of smoking cessation during pregnancy, data on cigarettes per day, urinary cotinine. and infant birth weight were obtained from 240 women. There were no significant differences in average birth weight between infants of women whocontinued to smoke but reduced their cigarette consumption by 50% or more and infants of women with lesser reductions. These results indicate that this birth weight comparison does not provide a valid estimate of the harm reduction associated with a reduction of 50% or more in cigarette consumption during pregnancy.     

Evidence for compensation in smokers of low yield cigarettes

To determine the relation of smoking low yield cigarettes (tar yield less than 15.0 mg and nicotine yield less than 1.0 mg per cigarette) to the number of cigarettes smoked per day, we analysed information provided on self-administered questionnaires by 7706 current, regular cigarette smokers. The mean age at starting to smoke and the mean number of years of smoking were not consistently different in smokers of low yield compared with smokers of high yield cigarettes. In contrast, at all ages in both men and women, smokers of low yield cigarettes smoked significantly more cigarettes per day than smokers of high yield cigarettes. The differences in the number of cigarettes smoked per day between smokers of low and high yield cigarettes were small--about 3 cigarettes per day in men and about 1 1/2 cigarettes per day in women. However, these small differences might translate to the smoking of as many as one billion more packs of cigarettes per year in the United States alone. The potential beneficial effect of the smoking of cigarettes whose yield per cigarette is lower must be weighed against a possible adverse effect of the smoking of more cigarettes if the relation between smoking low yield cigarettes and smoking more cigarettes is causal.     

Smoking characteristics and inhalation biochemistry in the Scottish population

Data from a cross-sectional random population sample of 10,359 middleaged Scottish men and women are used to investigate the relationships between self-reported tobacco consumption and three biochemical markers of tobacco inhalation: expired air carbon monoxide (CO), serum thiocyanate and serum cotinine. These data represent one of the largest samples of these biochemical markers yet analysed. The results show that, for each sex, the biochemical markers are highly correlated for smokers and for the entire sample of mixed smokers and non-smokers. CO is the preferred biochemical marker, in such groups, because it is the cheapest, is non-invasive and gives virtually instantaneous results. Self-reported daily cigarette consumption also correlates well with each of these biochemical markers, and so it appears that people are, in the context of population studies, mainly truthful about their smoking. The relationships with self-reported cigarette consumption are curvilinear with apparent levelling out of the gradient at around 25 cigarettes/day for cotinine and thiocyanate and at 40 cigarettes/day for CO. Sex differences are small, although thiocyanate is generally higher and cotinine generally lower in women with the same self-reported cigarette consumption as men. Amongst non-smokers, only cotinine is able to discriminate between self-reported levels of exposure to passive smoking. CO and thiocyanate are not suitable for measuring low levels of smoke inhalation, such as found in passive smokers.     

Comparison of smoking behavior change for SI and UC study groups. MRFIT Research Group.

BACKGROUND. The results of MRFIT smoking intervention program are presented for the 4,103 special intervention and 4,091 usual care men who reported smoking cigarettes at the first screening visit. RESULTS. Among the special intervention men, the reported cessation rate increased from 43.1% at 12 months to 48.9% at 72 months. The reported cessation rate among the usual care men increased from 13.5% at 12 months to 28.8% at 72 months. Among smokers who reported cessation at 72 months, 51.3% of special intervention men and 22.7% of usual care men had quit smoking within the first year and remained abstinent thereafter. Average thiocyanate and expired-air carbon monoxide served as objective measures of smoking and were significantly lower among the special intervention men than among the usual care men over the entire follow-up period. The reported cessation rates at 72 months varied according to initial levels of smoking. Smokers reporting 1-19 cigarettes per day at entry were more likely to quit than heavier smokers. For each category of smoking at entry (1-19, 20-39, and 40 or more cigarettes per day) significantly more special intervention than usual care smokers reported cessation. CONCLUSION. These results indicate that the MRFIT smoking intervention program was successful in promoting early cigarette smoking cessation and maintaining cessation over the entire trial for a large percentage of cigarette smokers.     

The economic costs of smoking and benefits of quitting for individual smokers

The results of a study that estimated the expected lifetime economic consequences of cigarette smoking for individual smokers are reported herein. The estimates were obtained by combining age- and sex-specific estimates of the incidence-based costs of three smoking-related diseases (lung cancer, coronary heart disease, and emphysema) with estimates of smokers' increased likelihood of developing these illnesses in each remaining year of life relative to nonsmokers. Estimates of the economic consequences of quitting based on these disease cost estimates and on estimates of exsmokers' probability of future disease relative to continuing smokers are also reported. Both the estimates of the economic costs of smoking and the benefits of quitting were calculated separately for men and women between the ages of 35 and 79 who were light, moderate, or heavy cigarette smokers. While the economic costs of smoking varied considerably by sex, age, and amount smoked, they were significant for all groups of smokers. Costs for a 40-year-old man, for example, ranged from $20,000 for a smoker of less than one pack of cigarettes per day to over $56,000 for a smoker of more than two packs of cigarettes per day. The economic benefits of quitting also were found to be sizable for all groups of smokers.     

Thiocyanate as an indicator of tobacco smoking.

This study demonstrates the suitability of serum thiocyanate as an indicator of tobacco smoke. The median serum level of smokers rises steadily from 51 μmol/liter in nonsmokers to 174 μmol/liter in smokers of more than 20 cigarettes/day. The method can be used in epidemiologic studies of smoking behavior and smoking cessation. To increase the accuracy of predicting smoking habits, this test can be used in conjunction with a determination of expired carbon monoxide.     

北京市成年人吸烟及被动吸烟情况分析

目的 了解北京市成年人群吸烟和被动吸烟情况。方法 于2008年10-11月采用多阶段分层随机整群抽样方法对北京市18～79岁的常住居民22206人,进行问卷调查。结果 全人群的吸烟率为33.2%,现在吸烟率为29.0%,男女性现在吸烟率分别为54.0%和2.9%,郊区与城区现在吸烟率分别为28.6%和25.6%;吸烟者以吸机制卷烟为主,人均吸烟量为14.7支/d,41.7%的人每天至少吸20支;吸第1支烟平均年龄为18.5岁,开始每天吸烟平均年龄为20.4岁;全市吸烟者戒烟率为15.4%,>50%吸烟者在2000年之后戒烟;43.4%的非吸烟者或戒烟者暴露于二手烟,其中40%的人每天被动吸烟,主要场所是家庭和工作场所。结论 北京市成年人吸烟状况严重,控烟下降不明显。     

Marriage to a smoker and lung cancer risk.

As part of a population-based case-control study of lung cancer in New Mexico, we have collected data on spouses' tobacco smoking habits and on-the-job exposure to asbestos. The present analyses include 609 cases and 781 controls with known passive and personal smoking status, of whom 28 were lifelong nonsmokers with lung cancer. While no effect of spouse cigarette smoking was found among current or former smokers, never smokers married to smokers had about a two-fold increased risk of lung cancer. Lung cancer risk in never smokers also increased with duration of exposure to a smoking spouse, but not with increasing number of cigarettes smoked per day by the spouse. Our findings are consistent with previous reports of elevated risk for lung cancer among never smokers living with a spouse who smokes cigarettes.     

Cross-sectional study on the relationship between body mass index and smoking, and longitudinal changes in body mass index in relation to change in smoking status: the Tromso Study

AIMS: To evaluate the effects of smoking and other lifestyle factors on body mass index (BMI), and changes in BMI in relation to changes in smoking status. METHODS: A cross-sectional study was performed on 10,920 males (3937 smokers) and 12,090 females (4343 smokers) who participated in the fourth Troms? Study (performed in 1994-95). A longitudinal study was performed on 2364 males (732 smokers in 1994-95) and 2738 females (942 smokers in 1994-95) who participated in both the fourth and the fifth Troms? studies (performed in 2001). RESULTS: In the cross-sectional study, current smokers of both genders had a lower BMI (25.0+/-3.4 vs. 25.5+/-3.2 kg/m(2) in males, and 23.9+/-3.9 vs. 25.3+/-4.6 kg/m( 2) in females, p<0.01), a lower degree of physical activity, and a higher consumption of coffee and alcohol than never-smokers. We found a U-shaped relationship between number of cigarettes smoked per day and BMI, with the lowest BMI in those smoking 6- 10 cigarettes per day. Heavy smokers and never-smokers had similar BMI. In the longitudinal study, continuing smokers had a smaller increase in BMI than those who gave up smoking. In those who gave up smoking, there was a significant, positive relationship between number of cigarettes smoked in 1994-95 and increase in BMI. CONCLUSIONS: There is a U-shaped relationship between number of cigarettes smoked per day and BMI. Smoking cessation is associated with an increase in weight as compared to those who continue smoking.     

Predictors of continued smoking over 25 years of follow-up in the normative aging study

OBJECTIVES: This study tested the hypothesis that high daily cigarette consumption and addiction to smoking are risk factors for the long-term continuation of smoking. METHODS: Using longitudinal data from 986 male smokers, we entered cigarettes per day, psychological addiction, age, and education into a survival analysis as predictors of continued smoking over a 25-year period. RESULTS: Younger men and those who smoked more cigarettes per day were more likely to remain smokers in the long term. Addiction and education level were not significant predictors of continued smoking. CONCLUSIONS: Heavier smokers are more at risk than lighter smokers for long-term smoking. It is therefore very important to provide smoking cessation treatments for heavy smokers as early as possible after the initiation of smoking.     

Saliva cotinine levels in smokers and nonsmokers

The authors collected by mail self-reported data on smoking habits and saliva samples that were analyzed for cotinine concentration in 222 smokers and 97 nonsmokers. Participants were members of the University of Geneva (Switzerland) in 1995. The 207 cigarette-only smokers smoked on average 10.7 cigarettes/day and had a median concentration of cotinine of 113 ng/ml. The cotinine concentration was moderately associated with the number of cigarettes smoked per day (+14 ng/ml per additional cigarette, p < 0.001, R2 = 0.45) and was 54 ng/ml higher in men than in women after adjustment for cigarettes per day and for the Fagerstr?m Test for Nicotine Dependence. The cotinine level was not associated with the nicotine yield of cigarettes (r= 0.08). In nonsmokers, the median concentration of cotinine was 2.4 ng/ml. The cotinine concentration was 1.5 times higher in nonsmokers whose close friends/spouses were smokers than in nonsmokers whose close friends/spouses were nonsmokers (p = 0.05). A cutoff of 7 ng/ml of cotinine distinguished smokers from nonsmokers with a sensitivity of 92.3% and a specificity of 89.7%; a cutoff of 13 ng/ml provided equally satisfactory results (sensitivity, 86.5%; specificity, 95.9%). This study provides evidence for the construct validity of both questionnaires and saliva cotinine for the assessment of active and passive exposure to tobacco smoke.     

Saliva thiocyanate: a chemical indicator of cigarette smoking in adolescents.

Denial and minimization in self-reports of cigarette smoking are probable common among youth and other groups where smoking is discouraged. Chemical measures may obtain more accurate measurement of smoking habits in those groups. One such measure, saliva thiocyanate (SCN), was evaluated in 1,419 eighth grade students. In that group, 54.9% of students admitted to regular smoking of greater than one pack/week had thiocyanates greater than or equal to 100 m g/ml compared to 2.3% nonsmokers at those levels. Of students who smoked greater than or equal to 10 cigarettes in the prior 24 hours, 66.7% were at or above 100 microgram/ml. Elevated SCN in nonsmokers was uncommon. Saliva SCN is a safe, inexpensive, and acceptable prevalence measurement for cigarette smoking. It can be used in place of self-reports to document smoking of greater than on pack/week in populations of youth.     

Consumption of 'low-yield' cigarettes: its frequency and relationship to serum thiocyanate.

To determine the use and possible health risks of low-yield cigarettes, we ascertained the cigarette brands and serum thiocyanate (SCN) levels of 2,561 adult smokers (age 25-74) in population-based samples of seven upper Midwestern communities during 1980-82. Brands were coded according to December 1981 Federal Trade Commission (FTC) ratings for "tar", nicotine, and carbon monoxide (CO). Compared to 1980 data from the National Center for Health Statistics for the United States as a whole, a greater proportion of smokers in these communities smoked low-yield brands. More people with higher education than lesser and more women than men smoked low-yield cigarettes. Greater proportions of older people (65-75 years) than younger people (less than 65 years) smoked cigarettes in the highest and lowest brand yield categories. SCN, adjusted for number of cigarettes smoked and for sex, was only weakly associated with brand ratings for "tar" (r = +.12), nicotine (R = +.11), and CO (r = +.15). Furthermore, the gradient in SCN between lowest and highest quintiles of brand strength was less than 16 per cent--much lower than the 300-500 per cent gradient in smoke components implied by FTC ratings. These data add to the evidence that smoking low-yield cigarettes may not be significantly less hazardous than smoking high-yield brands.     

Plasma levels and redox status of ascorbic acid and levels of lipid peroxidation products in active and passive smokers

Both active and passive smoking are regarded as risk factors for various diseases. To clarify the effects of active and passive smoking on plasma vitamin C levels and lipid peroxidation status, we examined the plasma levels of ascorbic acid (AA), its redox status [ratio of dehydroascorbate (DHAA) to total AA], the levels of thiobarbiturate reactive substance (TBARS), and the levels of lipid peroxides (LPO) in smokers, nonsmokers, and nonsmokers regularly exposed to environmental cigarette smoke (passive smokers). The study population consisted of 149 healthy males: 75 active smokers (consumption of > 15 cigarettes/day for more than 5 years), 36 passive smokers (more than 10 hr/week exposure to environmental cigarette smoke), and 38 nonsmokers (no cigarette smoke exposure). There were no significant differences in plasma TBARS and LPO levels among the three groups. Plasma levels of AA, the reduced form of vitamin C, were significantly lower in active smokers than in the combined nonsmoking groups (7.2 +/- 3.5 and 8.4 +/- 3.4 microg/mL, respectively; p < 0.05). Although no significant differences were found in plasma DHAA levels among the three groups, the ratios of DHAA to total AA were significantly higher in active and passive smokers than nonexposed nonsmokers (11.2, 10.3, and 7.1%, respectively; p < 0.05). These results indicate that passive smoking, as well as direct inhalation of cigarette smoke, affects the redox status of plasma AA. In passive smokers, the altered redox status of plasma AA suggests an oxidative stress.