Cigar and pipe smoking and lung cancer risk: a multicenter study from Europe

Cigarette smoking: cancer risks, carcinogens, and mechanisms

BACKGROUND

Cigarette smoking causes about 30% of all cancer mortality in developed countries. Although smoking is decreasing in developed countries, it is increasing in some developing countries.

DISCUSSION

Cigarette smoke contains over 60 well established carcinogens. There are strong links between some of these carcinogens and various types of smoking-induced cancers. Mechanisms by which cigarette smoke carcinogens cause cancer are well established and are discussed here.

CONCLUSIONS

A great deal is known about cigarette smoke carcinogens and the mechanisms by which they cause cancer. It is hoped that this will provide new insights for the prevention and cure of tobacco-induced cancer.

Effects of type of smoking (pipe, cigars or cigarettes) on biological indices of tobacco exposure and toxicity

Although all forms of smoking are harmful, smoking pipes or cigars is associated with lower exposure to the lethal products of tobacco products and lower levels of morbidity and mortality than smoking cigarettes. Cytochrome P-450-1A (CYP1A) is a major pathway activating carcinogens from tobacco smoke. Our primary aim was to compare CYP1A2 activity in individuals smoking pipes or cigars only, cigarettes only and in non-smokers. We studied 30 smokers of pipes or cigars only, 28 smokers of cigarettes only, and 30 non-smokers male subjects matched for age. CYP1A2 activity was assessed as the caffeine metabolic ratio in plasma. One-day urine collection was used for determining exposure to products of tobacco metabolism. Nitrosamine and benzo[a]pyrene DNA adducts were measured in lymphocytes. CYP1A2 activity was greater (p<0.0001) in cigarette smokers (median: 0.61; interquartile range: 0.52-0.76) than in pipe or cigar smokers (0.27; 0.21-0.37) and non-smokers (0.34; 0.25-0.42) who did not differ significantly. Urinary cotinine and 1-hydroxypyrene levels were higher in cigarette smokers than in pipe or cigar smokers and higher in the later than in non-smokers. DNA adducts levels were significantly lower in pipe or cigar smokers than in cigarette smokers. In multivariate analysis, cigarette smoking was the only independent predictor of CYP1A2 activity (p<0.0001) and of 1-hydroxypyrene excretion in urine (p=0.0012). In this study, pipe or cigar smoking was associated with lower exposure to products of tobacco metabolism than cigarette smoking and to an absence of CYP1A2 induction. Cigarette smoking was the only independent predictor of CYP1A2 activity in smokers. However, inhalation behaviour, rather than the type of tobacco smoked, may be the key factor linked to the extent of tobacco exposure and CYP1A2 induction. Our results provide a reasonable explanation for the results of epidemiological studies showing pipe or cigar smoking to present fewer health hazards than cigarette smoking.

Comparison of parental reports of smoking and residential air nicotine concentrations in children

BACKGROUND

Using questionnaires to assess children's residential exposure to environmental tobacco smoke (ETS) may result in misclassification from recall and response bias. Questionnaire data have frequently been validated against urinary cotinine measurements, but rarely against actual measurements of residential air nicotine.

OBJECTIVE

To compare questionnaire reported smoking with air nicotine concentrations in a large population of children and with urinary cotinine levels in a subpopulation; and to assess the potential impact of the symptom status of the children on the agreement between different measures of exposure.

METHODS

The authors assessed residential exposure to ETS in 347 German, 335 Dutch, and 354 Swedish preschool and schoolchildren by questionnaire and air nicotine measurements, and in a subset of 307 German children by urinary cotinine measurements. They then compared the different measures of ETS exposure.

RESULTS

In all countries, air nicotine concentrations increased with increasing questionnaire reported smoking in a dose-response fashion. Specificity and negative predictive values of questionnaire reports for nicotine concentrations were excellent. Sensitivity and positive predictive values were moderate to good. Excluding occasional smokers, the overall percentage of homes misclassified was 6.9%, 6.7%, and 5.1% in Germany, the Netherlands, and Sweden, respectively. Similar results were found for the agreement of urinary cotinine concentrations with questionnaire reports and air nicotine levels. There was no indication of underreporting by parents of symptomatic children.

CONCLUSION

Despite some misclassification, questionnaire reports are an inexpensive and valid estimate of residential ETS exposure among preschool and school children.

Alcohol, Tobacco and Caffeine Use: Spouse Similarity Processes

Spouse similarity research has been largely descriptive yet is of theoretical and empirical importance to understanding individual differences in substance use. The present study considers phenotypic assortment versus social homogamy processes for alcohol, tobacco, and caffeine consumption traits using an extended twin-spouse design. Whereas both assortment processes were supported for quantity of alcohol consumed, phenotypic assortment was supported for quantity of tobacco and caffeine consumed, and social homogamy for tobacco use status. Moderate heritable influences were found for all traits though no shared environmental influences were found beyond those due to social background influences, i.e. those pertaining to social homogamy. Swedish government policies in effect at the time of marriage selection may explain the presence of social homogamy for quantity of alcohol versus quantity of tobacco and caffeine consumed. Social homogamy may be more important for some substance use traits such as alcohol consumption and tobacco use status but not others.

The cumulative risk of lung cancer among current, ex- and never-smokers in European men

Recent analyses based on UK data indicate that people who stop smoking, even well into middle age, avoid most of their subsequent risk of lung cancer. We investigated whether similar absolute risks of lung cancer in men are found in other European countries with different smoking patterns and at different stages of their lung cancer epidemic. Using data for men from a multicentre case–control study of lung cancer in the UK, Germany, Italy and Sweden, and including 6523 lung cancer cases and 9468 controls, we combined odds ratio estimates with estimates of national lung cancer incidence rates to calculate the cumulative risk of lung cancer among men by age 75. Lung cancer cumulative risks by age 75 among continuing smokers were similar for the UK, Germany and Italy at 15.7, 14.3 and 13.8% respectively, whereas the cumulative risk among Swedish male smokers was 6.6%. The proportion of the risk of lung cancer avoided by quitting smoking before the age of 40 was comparable between the four countries, at 80% in Italy and 91% in the UK, Germany and Sweden. Similarly, the proportion of the excess risk avoided by quitting before the age of 50 ranged from 57% in Italy to 69% in Germany. Our results support the important conclusion that for long-term smokers, giving up smoking in middle age avoids most of the subsequent risk of lung cancer, and that lung cancer mortality in European men over the next three decades will be determined by the extent to which current smokers can successfully quit smoking.

Association between exclusive pipe smoking and mortality from cancer and other diseases

BACKGROUND

Although many studies have examined the adverse health effects of pipe smoking combined with other forms of tobacco use, few have included large numbers of exclusive pipe smokers. The prevalence of pipe smoking has declined since the 1960s, yet usage is still common regionally, especially among older populations.

METHODS

Using Cox proportional hazards models, we examined the association between pipe smoking and mortality from tobacco-related cancers and other diseases in a cohort of U.S. men enrolled in the Cancer Prevention Study II, an American Cancer Society prospective study. The cohort of 138 307 men included those who reported, in their 1982 enrollment questionnaire, exclusive current or former use of pipes (n = 15,263 men) or never use of any tobacco product (n = 123,044 men). Analyses were based on 23 589 men who died during 18 years of follow-up.

RESULTS

Current pipe smoking, compared with never use of tobacco, was associated with an increased risk of death from cancers of the lung (relative risk [RR] = 5.00, 95% confidence interval [CI] = 4.16 to 6.01), oropharynx (RR = 3.90, 95% CI = 2.15 to 7.08), esophagus (RR = 2.44, 95% CI = 1.51 to 3.95), colorectum (RR = 1.41, 95% CI = 1.15 to 1.73), pancreas (RR = 1.61, 95% CI = 1.24 to 2.09), and larynx (RR = 13.1, 95% CI = 5.2 to 33.1), and from coronary heart disease (RR = 1.30, 95% CI = 1.18 to 1.43), cerebrovascular disease (RR = 1.27, 95% CI = 1.09 to 1.48), and chronic obstructive pulmonary disease (RR = 2.98, 95% CI = 2.17 to 4.11). These risks were generally smaller than those associated with cigarette smoking and similar to or larger than those associated with cigar smoking. Relative risks of lung cancer showed statistically significant increases with number of pipes smoked per day, years of smoking, and depth of inhalation and decreases with years since quitting.

CONCLUSION

Results from this large prospective study suggest that pipe smoking confers a risk of tobacco-associated disease similar to cigar smoking.

Effects of reduced cigarette smoking on the uptake of a tobacco-specific lung carcinogen

BACKGROUND

Limited data are available on carcinogen uptake in smokers who reduce their smoking. To determine whether reducing the number of cigarettes smoked per day would lead to a corresponding reduction in carcinogen uptake, we measured levels of metabolites of the tobacco-specific lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in the urine of smokers who reduced their smoking for up to 26 weeks.

METHODS

We recruited 153 smokers, of whom 151 were randomly assigned to a reduction group or a waitlist group. In the reduction group of 102 smokers, we measured the metabolites 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronides (NNAL-Gluc) at two baseline times and at weeks 4, 6, 8, 12, and 26 after baseline. Smokers were then expected to reduce their number of cigarettes per day by 25% in weeks 0-2, 50% in weeks 2-4, and 75% in weeks 4-6 and to maintain the reduced level through week 26. In the waitlist group of 49 smokers, four baseline measurements over 7 weeks were made to assess the longitudinal stability of the metabolite measurements, and then the smokers began the reduction program. All statistical tests were two-sided.

RESULTS

For waitlist and reduction groups results were comparable. Statistically significant reductions in the lung carcinogen metabolites were observed at most intervals as smokers reduced the number of cigarettes smoked each day. However, the observed decreases were generally modest, always proportionally less than the reductions in cigarettes smoked per day, and sometimes transient. For example, among the 65 individuals in the reduction group who reduced cigarettes per day by 40% or more during weeks 4-12 after baseline, mean decreases in cigarettes per day were 53% (week 4), 74% (week 6), 75% (week 8), and 74% (week 12); whereas the corresponding mean reductions in NNAL plus NNAL-Gluc were 29%, 33%, 37%, and 29%. (P<.001 for all NNAL plus NNAL-Gluc values)

CONCLUSIONS

Statistically significant reductions in levels of urinary metabolites of a tobacco-specific lung carcinogen were achieved by reduction in smoking, but for most smokers, reductions were modest and transient.

Pipe and cigar smoking and major cardiovascular events, cancer incidence and all-cause mortality in middle-aged British men

BACKGROUND

Pipe and cigar smoking are still regarded by many as less hazardous to health than cigarette smoking.

METHODS

Prospective study of 7735 men aged 40-59 years drawn from general practices in 24 British towns with mean follow-up of 21.8 years. The outcome measures include major coronary heart disease (CHD) and stroke events, cancer incidence, and deaths from all causes.

RESULTS

There were 1133 major CHD events and 440 stroke events, 919 new cancers and 1994 deaths from all causes in the 7121 men with no diagnosed CHD, stroke, diabetes, or cancer at screening. Compared with never smokers, pipe/cigar smokers (primary and secondary combined) showed significantly higher risk of major CHD events (relative risk [RR] = 1.69, 95% CI: 1.32, 2.14) and stroke events (RR = 1.62, 95% CI: 1.08, 2.41) and of cardiovascular, non-cardiovascular, and total mortality (RR = 1.49, 95% CI: 1.13, 1.96, RR = 1.40, 95% CI: 1.08, 1.83 and RR = 1.44, 95% CI: 1.19, 1.74, respectively), after adjustment for lifestyle and biological characteristics. They also showed a significantly higher incidence of smoking-related cancers (RR = 2.67, 95% CI: 1.70, 4.26), largely due to lung cancer (RR = 4.35, 95% CI: 2.05, 8.94). Overall, the effects in pipe/cigar smokers were intermediate between never-smokers and light cigarette smokers, although risks for lung cancer were similar to light cigarette smokers.

CONCLUSION

Pipe and cigar smoking, whether primary or secondary, carries significant risk of smoking-related ill health.

Tobacco carcinogens, their biomarkers and tobacco-induced cancer

The devastating link between tobacco products and human cancers results from a powerful alliance of two factors - nicotine and carcinogens. Without either one of these, tobacco would be just another commodity, instead of being the single greatest cause of death due to preventable cancer. Nicotine is addictive and toxic, but it is not carcinogenic. This addiction, however, causes people to use tobacco products continually, and these products contain many carcinogens. What are the mechanisms by which this deadly combination leads to 30% of cancer-related deaths in developed countries, and how can carcinogen biomarkers help to reveal these mechanisms?

American Society of Clinical Oncology policy statement update: tobacco control--reducing cancer incidence and saving lives. 2003

As an international medical society dedicated to cancer prevention, the American Society of Clinical Oncology (ASCO) advocates a fundamental reform of United States and international policy toward addictive tobacco products. ASCO's goal is the immediate reduction of tobacco use and ultimate achievement of a tobacco-free world. The centerpiece of ASCO's policy is the recommendation for an independent commission to study the tobacco problem in all of its dimensions: social, medical, legal, and economic (both domestically and globally). The commission membership should include broad-based representation and expertise on tobacco issues. In ASCO's view, tobacco control efforts to date have been less than successful because they are too fragmented and incremental, leaving many important issues unaddressed. A more comprehensive solution could flow from this study, including input from a variety of government agencies involved with public health, agriculture, First Amendment and other legal considerations, and international trade. The study, within defined time limits, should culminate in a report that outlines a strategy for achieving immediate reduction of tobacco use and ultimate achievement of a tobacco-free world, including explicit plans and a timetable for implementation. Although this comprehensive approach to tobacco control will take many years to implement even under the best of circumstances, there are certain measures that could be undertaken immediately with meaningful impact on tobacco usage. These include: Increasing efforts to discourage tobacco use, particularly among the young Raising federal excise taxes by at least $2 per pack and encouraging states to consider tobacco taxes as a first resort in revenue enhancement Ensuring that tobacco settlement funds be devoted only to health-related projects, including medical treatment, biomedical research, and tobacco prevention efforts Requiring disclosure of all ingredients in tobacco products Comprehensively reforming third-party payment for tobacco cessation efforts Additional restriction of secondhand smoke in any places where the public may congregate Supporting necessary research into tobacco addiction, toxicities, and prevention strategies Enhancing global tobacco control, including a halt of United States government promotion of tobacco products

Epidemiology of lung cancer

In the United States, lung cancer remains the leading cause of cancer death in both men and women even though an extensive list of risk factors has been well-characterized. Far and away the most important cause of lung cancer is exposure to tobacco smoke through active or passive smoking. The reductions in smoking prevalence in men that occurred in the late 1960s through the 1980s will continue to drive the lung cancer mortality rates downward in men during the first portion of this century. This favorable trend will not persist unless further reductions in smoking prevalence are achieved.

Retrospective smoking history data collection for deceased workers: completeness and accuracy of surrogate reports

Few studies have considered the completeness and accuracy of smoking histories from surrogates for deceased workers. We surveyed 68 surrogates for uranium plant workers who completed smoking histories before their deaths. Completeness: 96% of surrogates answered definitively (yes or no) about overall smoking status (e.g., used any tobacco type), and 79 to 100% of those answered definitively about specific tobacco types. Of those reporting positive history, 50% to 67% answered detailed questions. Accuracy: Surrogates were accurate about overall smoking status (Kappa (kappa) = 0.75) compared with index self-report, but tended to underreport (P = 0.10). Spouses and nonspouses performed similarly. Accuracy by tobacco type was moderate (kappa = 0.21 to 0.56), with cigar smoking underreported. Surrogates for cigarette smokers underreported duration and amount smoked. Surrogates for deceased workers can report accurately on overall smoking status, but underreport other smoking habits.

Analysis of nonresponse bias in a population-based case-control study on lung cancer

The objective of this study was to identify characteristics of nonrespondents and late respondents in a population-based case-control study on lung cancer conducted in the city of Turin (Italy). Information about demographic and socioeconomic variables of 634 cases and 859 controls who responded to an interview, as well as of 154 cases and 154 controls who did not respond were obtained from census and the public register of Turin. The socioeconomic level of nonrespondents was high in cases but low in controls. Late respondent controls (i.e., individuals who responded after contact through their general practitioner) had socioeconomic characteristics comparable with those of nonrespondents, while they were similar to respondents with respect to demographic variables. The interview of late respondents halved, from 14 to 7%, the magnitude of the bias introduced by nonresponse on the estimate of the association between educational level and lung cancer. Nonresponse, associated with socioeconomic status, is an important potential source of bias in population-based case-control studies, which should always be considered and discussed. The direction and magnitude of the bias can be quantified. General practitioners may contribute to decrease nonresponse bias. Caution should be used in inferring characteristics of nonrespondents on the basis of those of late respondents.

Tobacco use and cancer causation: association by tumour type

In the second part of our review we describe the association between tobacco use and risk of specific cancer types. There is evidence for an established association of tobacco use with cancer of the lung and larynx, head and neck, bladder, oesophagus, pancreas, stomach and kidney. In contrast, endometrial cancer is less common in women who smoke cigarettes. There are some data suggesting that tobacco use increases the risk for myeloid leukaemia, squamous cell sinonasal cancer, liver cancer, cervical cancer, colorectal cancer after an extended latency, childhood cancers and cancer of the gall bladder, adrenal gland and small intestine. Other forms of cancer, including breast, ovarian and prostate cancer, are unlikely to be linked to tobacco use.

Cigarette smoking and lung cancer: chemical mechanisms and approaches to prevention

Much is now known about the carcinogens in cigarette smoke, their conversion to forms that react with DNA, and the miscoding properties of the resulting DNA adducts that cause the many genetic changes known to exist in human lung cancer. The chronic exposure of pulmonary DNA to a multitude of metabolically activated carcinogens is consistent with our current understanding of cancer as a disease resulting from many changes in key genes regulating growth. This review illustrates how this solid foundation of knowledge can be used to find new ways to prevent lung cancer. Three prevention-related topics are discussed: human uptake of tobacco carcinogens as a way of assessing risk and investigating mechanisms; individual differences in the metabolic activation and detoxification of carcinogens, which may relate to cancer susceptibility; and chemoprevention of lung cancer in smokers and ex-smokers. These new approaches are necessary as adjuncts to education and cessation efforts, which despite some success have not eliminated tobacco smoking.

Lung cancer near an industrial site in Lithuania with major emissions of airway irritants

To assess the relation between air pollution with airway irritants, including sulfuric acid and lung cancer, a case-control study was performed near an industry producing sulfuric acid and fertilizers in Kedainiai county, central Lithuania. The county had the highest lung cancer rates of the country among men. Between 1967 and 1973, the levels of sulfuric acid exceeded 500 microg/m(3) within 2 km of the industry and 100 microg/m(3) more than 5 km away. A total of 277 men who were diagnosed as having lung cancer during 1981-1991 in Kedainiai county were included as well as 1,108 population controls. Information on residential history since 1960, smoking habits, occupations and workplaces during lifetime was obtained from questionnaires mailed to next-of-kin. The relative risk of lung cancer associated with living within approximately 5 km from the plant was 1.02 (95% CI: 0.76-1.38) compared to those who had never lived in this area. No relation with distance or duration of residence was observed. Furthermore, workers at the plant did not have an increased lung cancer risk. The relative risk of lung cancer associated with smoking was 21.2 (95% CI: 7.51; 60.1) for current smokers and 14.0 (95% CI: 4.88; 40.3) for exsmokers. The duration of smoking, a low age at start and amount of cigarettes smoked daily were positively associated with lung cancer risk. Smoking levels appeared more pronounced among study controls than in the rest of the country. Our study could not confirm earlier evidence of an association between exposure to airway irritants, such as sulfuric acid and lung cancer. Smoking is the major determinant of the risk of lung cancer in men in Kedainiai county. It is probable that higher smoking rates constitute the main reason for the increased lung cancer risk among men in this area.

Epidemiology, etiology, and prevention of lung cancer

Over the past century, lung cancer has gone from an obscure disease to the leading cause of cancer death worldwide. Initially an epidemic disease among men in industrialized nations, lung cancer now has become the leading cancer killer in both sexes in the United States and an increasingly common disease of both sexes in developing countries. Lung cancer incidence largely mirrors smoking prevalence, with a latency period of several decades. Other important risk factors for the development of lung cancer include environmental exposure to tobacco smoke, radon, occupational carcinogens, and pre-existing nonmalignant lung disease. Studies in molecular biology have elucidated the role that genetic factors play in modifying an individual's risk for lung cancer. Although chemopreventive agents may be developed to prevent lung cancer, prevention of smoking initiation and promotion of smoking cessation are currently the best weapons to fight lung cancer. No other malignancy has been shown to have such a strong epidemiologic relation between a preventable behavior and incidence of disease. Despite this knowledge, more than 20% of all Americans smoke, and tobacco use is exploding in developing countries. Based on current and projected smoking patterns, it is anticipated that lung cancer will remain the leading cause of cancer death in the world for decades to come.

Hospitalizations among female home-helpers in Denmark, 1981-1997

BACKGROUND

Occupational health problems among home-helpers have been reported in a series of studies, and the need for intervention has been pointed out. To facilitate decisions regarding interventions and to establish baseline values for future evaluation of preventive efforts, the present study aimed to elucidate the disease pattern among female home-helpers in Denmark.

METHODS

Cohorts of all 20-59-year-old Danish female home-helpers in the years 1981, 1986, 1991, and 1994 were formed, to calculate age standardized hospitalization ratios (SHR) and time trends (1981-1997) for a large variety of diagnostic aggregations.

RESULTS

Significantly high SHRs were found for injuries, infectious and parasitic diseases, and for diseases of the nervous system, circulatory system, the respiratory organs, digestive system, and the musculoskeletal system. When adjusting for social group the SHRs for varicose veins, ischemic heart diseases (IHD), and musculoskeletal disorders were still significantly high while the SHR for malignant neoplasm of respiratory organs became significantly low. The time trends revealed increased relative risks for IHD and asthma, and a decreasing relative risk for duodenal ulcer.

CONCLUSIONS

Employment in the Danish home-help sector is associated with an elevated hospitalization risk due to many work-related diseases.

Environmental causes of human cancers

Epidemiological studies have clearly shown a causal association between tobacco exposure and various human cancers, hepatitis B and C infection and hepatocellular carcinoma, human papilloma viruses and cervical cancer, and the occupational origin of certain human cancers is well established. The identification of the environmental causes of human cancers has been a long and difficult process. Much remains to be understood about the role of specific components of the diet and the interaction of different risk factors in the aetiology of human cancers. Withstanding the progress made on the understanding of the cancer process and their potential impact in the therapy of cancer, primary prevention remains, in developed and developing countries, the most effective measure to reduce cancer mortality.

Lung cancer and cigarette smoking in Europe: an update of risk estimates and an assessment of inter-country heterogeneity

Ten case-control studies have been carried out in 6 European countries to investigate the major risk factors for lung cancer. Carcinogenic effect from cigarette smoke was the most relevant interest in our study, which has included 7,609 cases of lung cancer and 10,431 controls, mainly population based. The results indicate elevated odds ratios (ORs; 23.9 among men and 8.7 among women) with attributable risks exceeding 90% for men and close to 60% for women. A large, and statistically significant, variability of the results across countries was detected after adjusting for the most common confounding variables, and after controlling, at least in part, for the instability of the ORs due to the small number of non-smokers in some of the study subsets. This pattern of lung cancer risk associated with cigarettes smoke, across different European regions, reflects inherent characteristics of the studies as well as differences in smoking habits, particularly calendar periods of starting, and it is likely to have been influenced by effect modifiers like indoor radon exposure, occupation, air pollution and dietary habits.

Cigar, pipe, and cigarette smoking as risk factors for periodontal disease and tooth loss

BACKGROUND

Our purpose was to test the hypotheses that cigar and pipe smoking have significant associations with periodontal disease and cigar, pipe, and cigarette smoking is associated with tooth loss. We also investigated whether a history of smoking habits cessation may affect the risk of periodontal disease and tooth loss.

METHODS

A group of 705 individuals (21 to 92 years-old) who were among volunteer participants in the ongoing Baltimore Longitudinal Study of Aging were examined clinically to assess their periodontal status and tooth loss. A structured interview was used to assess the participants' smoking behaviors with regard to cigarettes, cigar, and pipe smoking status. For a given tobacco product, current smokers were defined as individuals who at the time of examination continued to smoke daily. Former heavy smokers were defined as individuals who have smoked daily for 10 or more years and who had quit smoking. Non-smokers included individuals with a previous history of smoking for less than 10 years or no history of smoking.

RESULTS

Cigarette and cigar/pipe smokers had a higher prevalence of moderate and severe periodontitis and higher prevalence and extent of attachment loss and gingival recession than non-smokers, suggesting poorer periodontal health in smokers. In addition, smokers had less gingival bleeding and higher number of missing teeth than non-smokers. Current cigarette smokers had the highest prevalence of moderate and severe periodontitis (25.7%) compared to former cigarette smokers (20.2%), and non-smokers (13.1%). The estimated prevalence of moderate and severe periodontitis in current or former cigar/pipe smokers was 17.6%. A similar pattern was seen for other periodontal measurements including the percentages of teeth with > or = 5 mm attachment loss and probing depth, > or = 3 mm gingival recession, and dental calculus. Current, former, and non- cigarette smokers had 5.1, 3.9, and 2.8 missing teeth, respectively. Cigar/pipe smokers had on average 4 missing teeth. Multiple regression analysis also showed that current tobacco smokers may have increased risks of having moderate and severe periodontitis than former smokers. However, smoking behaviors explained only small percentages (<5%) of the variances in the multivariate models.

CONCLUSION

The results suggest that cigar and pipe smoking may have similar adverse effects on periodontal health and tooth loss as cigarette smoking. Smoking cessation efforts should be considered as a means of improving periodontal health and reducing tooth loss in heavy smokers of cigarettes, cigars, and pipes with periodontal disease.

Tobacco-related diseases. Is there a role for antioxidant micronutrient supplementation?

It is clear that smoking causes an increase in free radicals, reactive nitrogen and oxygen species (RNS and ROS, respectively), and that cigarette smoking is associated with increases in the incidence and severity of several diseases including atherosclerosis, cancer, and chronic obstructive lung disease. Although there is still no unequivocal evidence that oxidative stress is a contributor to these diseases or that an increased intake of antioxidant nutrients is beneficial, the observation that smokers have lower circulating levels of some of these nutrients, raises concern. This article discusses the possible links between the observed oxidant-induced damage related to tobacco smoking, effects on cellular mechanisms, and their potential involvement in the causation and enhancement of disease processes.