Uncovering the effects of smoking: historical perspective

The impact of stress and lifestyle factors on short-term sickness absence in a large Danish industrial company

Objectives: Work-related stress and certain lifestyles have been associated with sickness absence among employees. We analysed relations between stress and lifestyles (as risk factors) and short-term sickness absence among employees of a large Danish industrial company. Moreover, we analysed the impact of risk factors on short-term sickness absence. Methods: A self-administered questionnaire was completed by 7753 employees (67% response rate). Relations between risk factors (dyssomnia, low physical activity, alcohol, smoking, unhealthy food habits, overweight and stress) and short-term sickness absence were analysed by calculating etiologic fractions and binary logistic regression. Relations between the number of risk factors and short-term sickness absence were also analysed. Finally, the cost of short-term sickness absence from risk factors was estimated to illustrate the potential savings in avoided loss of productivity that could be gained from intervention programmes. Results: Stress, overweight, smoking and dyssomnia are significantly related to short-term sickness absence. Etiologic fractions revealed that these factors were associated with between 29.8% and 37.8% of short-term sickness absence. The number of risk factors was also related to the risk and length of sickness absence. Conclusions: This study identified risk factors that could be addressed by intervention programmes to reduce short-term sickness absence. Based on the results, focus on the risk factors that account for most short-term sickness absence and reduction of the number of risk factors could potentially reduce short-term sickness absence. A 30% reduction is equivalent to an avoidance of a loss of productivity of 4.5%, corresponding to €9.4 million per year.

Mendelian randomization analysis of C-reactive protein on colorectal cancer risk

BACKGROUND

Chronic inflammation is a risk factor for colorectal cancer (CRC). Circulating C-reactive protein (CRP) is also moderately associated with CRC risk. However, observational studies are susceptible to unmeasured confounding or reverse causality. Using genetic risk variants as instrumental variables, we investigated the causal relationship between genetically elevated CRP concentration and CRC risk, using a Mendelian randomization approach.

METHODS

Individual-level data from 30 480 CRC cases and 22 844 controls from 33 participating studies in three international consortia were used: the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT) and the Colon Cancer Family Registry (CCFR). As instrumental variables, we included 19 single nucleotide polymorphisms (SNPs) previously associated with CRP concentration. The SNP-CRC associations were estimated using a logistic regression model adjusted for age, sex, principal components and genotyping phases. An inverse-variance weighted method was applied to estimate the causal effect of CRP on CRC risk.

RESULTS

Among the 19 CRP-associated SNPs, rs1260326 and rs6734238 were significantly associated with CRC risk (P = 7.5 × 10-4, and P = 0.003, respectively). A genetically predicted one-unit increase in the log-transformed CRP concentrations (mg/l) was not associated with increased risk of CRC [odds ratio (OR) = 1.04; 95% confidence interval (CI): 0.97, 1.12; P = 0.256). No evidence of association was observed in subgroup analyses stratified by other risk factors.

CONCLUSIONS

In spite of adequate statistical power to detect moderate association, we found genetically elevated CRP concentration was not associated with increased risk of CRC among individuals of European ancestry. Our findings suggested that circulating CRP is unlikely to be a causal factor in CRC development.

Psychotic experiences and general medical conditions: a cross-national analysis based on 28 002 respondents from 16 countries in the WHO World Mental Health Surveys

BACKGROUND

Previous work has identified associations between psychotic experiences (PEs) and general medical conditions (GMCs), but their temporal direction remains unclear as does the extent to which they are independent of comorbid mental disorders.

METHODS

In total, 28 002 adults in 16 countries from the WHO World Mental Health (WMH) Surveys were assessed for PEs, GMCs and 21 Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) mental disorders. Discrete-time survival analyses were used to estimate the associations between PEs and GMCs with various adjustments.

RESULTS

After adjustment for comorbid mental disorders, temporally prior PEs were significantly associated with subsequent onset of 8/12 GMCs (arthritis, back or neck pain, frequent or severe headache, other chronic pain, heart disease, high blood pressure, diabetes and peptic ulcer) with odds ratios (ORs) ranging from 1.3 [95% confidence interval (CI) 1.1-1.5] to 1.9 (95% CI 1.4-2.4). In contrast, only three GMCs (frequent or severe headache, other chronic pain and asthma) were significantly associated with subsequent onset of PEs after adjustment for comorbid GMCs and mental disorders, with ORs ranging from 1.5 (95% CI 1.2-1.9) to 1.7 (95% CI 1.2-2.4).

CONCLUSIONS

PEs were associated with the subsequent onset of a wide range of GMCs, independent of comorbid mental disorders. There were also associations between some medical conditions (particularly those involving chronic pain) and subsequent PEs. Although these findings will need to be confirmed in prospective studies, clinicians should be aware that psychotic symptoms may be risk markers for a wide range of adverse health outcomes. Whether PEs are causal risk factors will require further research.

The epidemiology of lung cancer

The incidence and mortality from lung cancer is decreasing in the US due to decades of public education and tobacco control policies, but are increasing elsewhere in the world related to the commencement of the tobacco epidemic in various countries and populations in the developing world. Individual cigarette smoking is by far the most common risk factor for lung carcinoma; other risks include passive smoke inhalation, residential radon, occupational exposures, infection and genetic susceptibility. The predominant disease burden currently falls on minority populations and socioeconomically disadvantaged people. In the US, the recent legalization of marijuana for recreational use in many states and the rapid growth of commercially available electronic nicotine delivery systems (ENDS) present challenges to public health for which little short term and no long term safety data is available.

Tobacco use does not influence the response to non-pharmacologic depression treatment: A secondary analysis of the Regassa randomized controlled trial

Behavioural interventions show promising results among patients with mild- to moderate depression. However, whether tobacco use moderates the effects of these interventions is not known. In the present study, we examined whether patients suffering from mild-to-moderate depression differed in their response to prescribed physical exercise or internet-based cognitive behavioural therapy (ICBT) according to their current tobacco use. We conducted a secondary analysis of data from 740 participants in a multicentre randomised controlled trial comparing physical exercise, internet-based cognitive behavioural therapy and treatment as usual (Regassa study). Information on current daily tobacco use was self-reported at baseline. Linear and logistic regression were used to examine the treatments' effect (reduction in depression score) in the subgroups of tobacco users (n=154) and non-users (n=586). We found that baseline tobacco use did not significantly moderate the association between treatment type and post-treatment depression severity. Both interventions (exercise and ICBT) resulted in a reduction of depression scores that was similar among non-users and users of tobacco, albeit formally statistically significant only among non-users. Physical exercise on prescription and ICBT can be used in the clinical management of depressed patients, with similar prognostic advantage among tobacco users and non-users.

Association of Chlamydia pneumoniae immunoglobulin G antibodies with the risk of lung cancer among non-smoking women in Liaoning, China

The role of Chlamydia pneumoniae in the cause of lung cancer is controversial. In this study, we investigated the association between C. pneumoniae immunoglobulin (Ig) G antibodies and risk of lung cancer among non-smoking women. C. pneumoniae IgG antibody levels were compared between 192 adult Chinese women who met the diagnostic criteria of lung cancer and 90 healthy controls. C. pneumoniae IgG antibodies were tested with the use of an enzyme-linked immunosorbent assay. The prevalence of C. pneumoniae IgG seropositivity was 61.98% of cases and 28.89% of controls (P < 0.05). According to the results of the multiple logistic analysis model, the odds ratios for C. pneumoniae IgG antibody seropositivity, body mass index, and educational levels were 3.919 (P < 0.001), 0.731 (P= 0.274), and 1.646 (P= 0.069), respectively. C. pneumoniae infection may be a risk factor for lung cancer.

The effect of intensive care unit admission on smokers' attitudes and their likelihood of quitting smoking

We sought to estimate the proportion of patients admitted to a metropolitan intensive care unit (ICU) who were current smokers, and the relationships between ICU survivors who smoked and smoking cessation and/or reduction six months post-ICU discharge. We conducted a prospective cohort study at a metropolitan level III ICU in Melbourne, Victoria. One hundred consecutive patients who met the inclusion criteria were included in the study. Inclusion criteria consisted of patients who were smokers at time of ICU admission, had an ICU length of stay greater than one day, survived to ICU discharge, and provided written informed consent. A purpose-designed questionnaire which included the Fagerstrom test for nicotine dependence and evaluation of patients' attitude towards smoking cessation was completed by participants following ICU discharge and prior to hospital discharge. Participants were re-interviewed over the phone at six months post-ICU discharge. Of the 1,062 patients admitted to ICU, 253 (23%) were current smokers and 100 were enrolled. Six months post-ICU discharge, 28 (33%) of the 86 participants who were alive and contactable had quit smoking and 35 (41%) had reduced smoking. The median number of reported cigarettes smoked per day reduced by 40%. Participants who initially believed their ICU admission was smoking-related were more likely to have quit six months post-ICU discharge (odds ratio 2.98; 95% confidence interval 1.07 to 8.26; <i>P</i>=0.036). Six months post-ICU discharge, 63/86 (74%) of participants had quit or reduced their smoking. Further research into targeted smoking cessation counselling for ICU survivors is indicated.

Smoking Related Systemic and Oral Diseases

This article reviewed smoking related systemic diseases and oral diseases. Smoking is related to lung cancer, cardiovascular diseases and many other systemic diseases. Cigarette smoke affects the oral cavity first, so it is evident that smoking has many negative influences on oral cavity, for example, staining of teeth and dental restorations, wound healing, reduction of the ability to smell and taste, and development of oral diseases such as oral cancer, periodontitis, smoker’s palate, smoker’s melanosis, hairy tongue, leukoplakia, oral candidiasis and implant survival rate. The article also discusses the relationship between smoking and dental caries in detail.

Cancer incidence in the AGRICAN cohort study (2005-2011)

BACKGROUND

Numerous studies have been conducted among farmers, but very few of them have involved large prospective cohorts, and few have included a significant proportion of women and farm workers. Our aim was to compare cancer incidence in the cohort (overall, by sex, and by work on farm, occupational status and pesticide use) within the general population.

METHODS

More than 180,000 participants in the AGRICAN cohort were matched to cancer registries to identify cancer cases diagnosed from enrolment (2005-2007) to 31st December 2011. We calculated standardized incidence ratios (SIRs) and 95% confidence intervals (95%CIs).

RESULTS

Over the period, 11,067 incident cancer cases were identified (7304 men and 3763 women). Overall cancer incidence did not differ between the cohort and the general population. Moreover, SIRs were significantly higher for prostate cancer (SIR=1.07, 95%CI 1.03-1.11) and non-Hodgkin lymphoma (SIR=1.09, 95%CI 1.01-1.18) among men, skin melanoma among women (SIR=1.23, 95%CI 1.05-1.43) and multiple myeloma (men: SIR=1.38, 95%CI 1.18-1.62; women: SIR=1.26, 95%CI 1.02-1.54). In contrast, SIRs were lower for upper aerodigestive tract and respiratory cancers. Increase in risk was greater in male farm workers for prostate and lip cancer, in female farm workers for skin melanoma, and in male farm owners for multiple myeloma. Moreover, incidence of multiple myeloma and skin melanoma was higher among male and female pesticide users respectively.

CONCLUSION

We found a decreased incidence for tobacco-related cancers and an increased incidence of prostate cancers, skin melanoma and multiple myeloma. Specific subgroups had a higher cancer incidence related to occupational status and pesticide use.

A proposed World Council on Epidemiology and Causation: summary of feedback and considerations in an international workshop

Rigorous evaluation of associations in epidemiology is essential, especially given big data, data mining, and hypothesis-free analyses. There is a precedent in making judgments on associations in the monographs of the International Agency for Research on Cancer; however, only the carcinogenic effects of exposures are examined. The idea of a World Council of Epidemiology and Causality to undertake rigorous, independent, comprehensive examination of associations has been debated, including in a workshop at the International Epidemiology Association's 20^th World Congress of Epidemiology, 2014. The objective of the workshop was both to, briefly, debate the idea and set out further questions and next steps. The principal conclusion from feedback including from the workshop is that the World Council of Epidemiology and Causality idea, notwithstanding challenges, has promise and deserves more debate. The preferred model is for a small independent body working closely with relevant partners with a distributed approach to tasks. Recommendations are contextualized in contemporary approaches in causal thinking in epidemiology.

Crosstalk between oral and general health status in e-smokers

Electronic cigarette (e-cigarette) simulates the act of tobacco smoking by vaporizing a mixture of propylene glycol, nicotine, and flavoring agents. e-cigarette has been proposed as a product able to aid to stop smoking. The aim of the study is to verify the clinical variations of periodontal health induced by e-cigarettes use and, moreover, to investigate about the awareness of the e-smokers about their health variations and about their hypothetical need to turn back to smoke combustible cigarettes.This clinical observational pilot study involved 110 out of 350 smokers, who switched to e-cigarette. Patients were subjected to oral examinations. A questionnaire to self-assess the variations of some parameters of general health, and to self-assess the need to smoke combustible cigarettes, was distributed to such subjects involved in the study.At the end of the study, we registered a progressive improvement in the periodontal indexes, as well as in the general health perception. Finally, many patients reported an interesting reduction in the need to smoke.In the light of this pilot study, the e-cigarette can be considered as a valuable alternative to tobacco cigarettes, but with a positive impact on periodontal and general health status.

Tobacco Smoke–Induced Lung Cancer in Animals—A Challenge to Toxicology (?)

Tobacco smoke is a known human carcinogen that primarily produces malignant lesions in the respiratory tract, although it also affects multiple other sites. A reliable and practical animal model of tobacco smoke–induced lung cancer would be helpful for in studies of product modification and chemoprevention. Over the years, many attempts to reproduce lung cancer in experimental animals exposed to tobacco smoke have been made, most often with negative or only marginally positive results. In hamsters, malignant lesions have been produced in the larynx, but not in the deeper lung. Female rats and female B6C3F1 mice, when exposed over lifetime to tobacco smoke, develop tumors in the nasal passages and also in the lung. Contrary to what is seen in human lung cancers, most rodent tumors are located peripherally and only about half of them show frank malignant features. Distant metastases are extremely rare. Male and female strain A mice exposed to 5 months to tobacco smoke and then kept for another 4 months in air respond to tobacco smoke with increased lung tumor multiplicities. However, the increase over background levels is comparatively small, making it difficult to detect significant differences when the effects of chemopreventive agents are evaluated. On the other hand, biomarkers of exposure and of effect as well as evaluation of putative carcinogenic mechanisms in rats and mice exposed to tobacco smoke allow detection of early events and their modification by different smoke types or chemopreventive agents. The challenge will be to make such data broadly acceptable and accepted in lieu of having to do more and more long term studies involving larger and larger number of animals.

Causes of death behind low life expectancy of Danish women

Aims: The authors examined causes of death contributing to the relatively high mortality of Danish women born 1915—45, and evaluated the impact of smoking related causes of death. Methods: Age—period—cohort analysis of mortality of Danish women aged 40—89 in 1960—98. Estimate of the negative curvature in parabola patterns for 50 causes of death. Results: A total of 34 causes of death contributed to the relatively high mortality for women born 1915—45. The main contribution came from smoking-related causes of death. Conclusion: The results indicate a high smoking prevalence to be the main explanation behind the relatively low life expectancy of Danish women born 1915—45.

Psychosocial sequelae of cannabis use and implications for policy: findings from the Christchurch Health and Development Study

BACKGROUND

The Christchurch Health and Development Study is a longitudinal study of a birth cohort of 1265 children who were born in Christchurch, New Zealand, in 1977. This cohort has now been studied from birth to the age of 35.

SCOPE OF THIS REVIEW

This article examines a series of findings from the CHDS that address a range of issues relating to the use of cannabis amongst the cohort. These issues include: (a) patterns of cannabis use and cannabis dependence; (b) linkages between cannabis use and adverse educational and economic outcomes; (c) cannabis and other illicit drug use; (d) cannabis and psychotic symptoms; (e) other CHDS findings related to cannabis; and (f) the consequences of cannabis use for adults using cannabis regularly.

FINDINGS

In general, the findings of the CHDS suggest that individuals who use cannabis regularly, or who begin using cannabis at earlier ages, are at increased risk of a range of adverse outcomes, including: lower levels of educational attainment; welfare dependence and unemployment; using other, more dangerous illicit drugs; and psychotic symptomatology. It should also be noted, however, that there is a substantial proportion of regular adult users who do not experience harmful consequences as a result of cannabis use.

CONCLUSIONS

Collectively, these findings suggest that cannabis policy needs to be further developed and evaluated in order to find the best way to regulate a widely-used, and increasingly legal substance.

Correlations between supra- and subgingival clinical parameters in smokers and individuals who have never smoked

Introduction Smoking is a risk factor for prevalence, severity and progression of periodontal disease and appears to suppress marginal periodontium inflammatory response. Purpose To correlate Visible Plaque Index (VPI) and Gingival Bleeding Index (GBI) in smokers and never-smokers, as well as GBI and bleeding on probing (BOP ) in these groups. Material and method We used baseline data of one quasi-experimental study in which 11 smokers and 14 subjects who never smoked were submitted to clinical periodontal examinations between September 2010 and October 2011. Result The correlation between VPI and GBI was positive for both groups, it was strong and statistically significant in subjects who had never smoked and moderate in smokers. Regarding GBI and BOP correlations were moderate for smokers and weaker for individuals who had never smoked. Conclusion Smokers have lower strength correlation between VPI and GBI compared to individuals who had never smoked resulting in a less pronounced marginal gingival bleeding.

Advance modern medicine with clinical case reports

Randomized clinical trial (RCT) can fail to demonstrate the richness of individual patient characteristics. Given the unpredictable nature of medicine, a patient may present in an unusual way, have a strange new pathology, or react to a medical intervention in a manner not seen before. The publication of these novelties as case reports is a fundamental way of conveying medical knowledge. Throughout history there have been famous case studies that shaped the way we view health and disease. Case reports can have the following functions: (I) descriptions of new diseases; (II) study of mechanisms; (III) discovery new therapies; (IV) recognition of side effects; and (V) education. Before submitting a case report, it is worthwhile to refer to the Case Report Check Sheet described by Green and Johnson [2006].

Smoking-attributable mortality in Morocco: results of a prevalence-based study in Casablanca

BACKGROUND

Tobacco control measurements' had little impact on smoking prevalence in Morocco. The aim of this study is to provide first data on smoking attributable mortality in Morocco.

METHOD

The Smoking-Attributable Mortality, Morbidity and Economic Costs (SAMMEC) software was used to estimate the smoking attributable mortality (SAM) in Casablanca region in 2012. Smoking prevalence and mortality data of people aged 35 years or older were obtained from the national survey on tobacco "Marta" and from Health Ministry Mortality System, respectively.

RESULTS

Of the 5261deaths of persons aged 35 years and older, 508 (9.7%) were attributable to cigarette smoking. This total represents 16.2% of all male deaths (n =448) and 2.0% (n =80) of all female deaths in this region. The leading four causes of smoking attributable deaths were lung cancer (177), chronic airways obstruction (76), ischemic heart disease (39), and cerebrovascular disease (31).

CONCLUSION

Tobacco use caused one out of six deaths in Casablanca in 2012. Four leading causes (lung cancer, ischemic heart disease, cerebrovascular disease and chronic airways obstruction,) accounted for 51.6% of SAM. Effective and comprehensive actions must be taken in order to slow this epidemic in Morocco.

Cancer risk in patients with manifest vascular disease: effects of smoking, obesity, and metabolic syndrome

BACKGROUND

Patients with vascular disease may be at increased risk of cancer because of shared risk factors and common pathogenesis.

METHODS

Patients with vascular disease (n = 6,172) were prospectively followed for cancer incidence. Standardized incidence ratios (SIRs) were calculated to compare the cancer incidence of the study population with that of the general population. Multivariable-adjusted hazard ratio's (HRs) of cancer were estimated for smoking status, pack-years, body mass index, waist circumference and visceral adipose tissue (VAT), and metabolic syndrome (MetS).

RESULTS

During a median follow-up of 5.5 years, 563 patients were diagnosed with cancer. Patients with vascular disease were at increased risk of cancer [SIR = 1.19; 95% confidence interval (CI), 1.10-1.29]. Specifically, risk of lung cancer (SIR = 1.56; 95% CI, 1.31-1.83), as well as bladder cancer (SIR = 1.60; 95% CI, 1.11-2.24) and cancer of the lip, oral cavity, or pharynx in men (SIR = 1.51; 95% CI, 0.89-2.39), and colorectal (SIR = 1.71; 95% CI, 1.11-2.53) and kidney cancer (SIR = 2.92; 95% CI, 1.05-6.38) in women was increased. A relation between smoking and cancer risk was observed (HR for current smokers = 1.37; 95% CI, 1.05-1.73), whereas an increase in VAT was associated with higher breast cancer risk in women (HR = 1.42; 95% CI, 1.03-1.96). No relation between MetS and cancer risk was found.

CONCLUSIONS

Patients with vascular disease have a 19% higher cancer risk compared to the general population. Smoking increased cancer risk and abdominal obesity is a risk factor for breast cancer in female patients with vascular disease.

IMPACT

These results call for awareness of the increased cancer risk in patients with vascular disease among physicians and underline the necessity of lifestyle improvement not only for reducing cardiovascular risk.

Cigarette smoke extract induces differential expression levels of beta-defensin peptides in human alveolar epithelial cells

Background

The damaging effects of cigarette smoke on the lungs are well known in terms of cancer risks. Additional molecular changes within the lung tissue can also occur as a result of exposure to cigarette smoke. The human β-defensin (hBD) class of antimicrobial peptides is the focus of our research. In addition to antimicrobial activity, β-defensins also have immunomodulatory functions. Over 30 previously unrecognized β-defensin genes have recently been identified in the human genome, many with yet to be determined functions. We postulated that altered β-defensin production may play a role in the pathogenesis observed in the lungs of smokers. Our hypothesis is that cigarette smoke exposure will affect the expression of β-defensins in human lung alveolar epithelial cells (A549).

Methods

We exposed A549 cells to cigarette smoke extract (CSE) and measured the changes in mRNA levels of several antimicrobial peptides by quantitative real-time PCR, and directly observed peptide expression in cells by immunofluorescence (IF) microscopy.

Results

We found that hBD3, hBD5, and hBD9 gene expression was upregulated in A549 cells exposed to CSE. HBD1, hBD8, hBD18 and LL-37 gene expression did not significantly change upon exposure to CSE. Expression of hBD3 and hBD4 peptides was visualized by IF.

Conclusions

This differential expression suggests that hBD3, hBD5, and hBD9 may play a role in the changes to the lung tissue observed in smokers. Establishing differential β-defensin expression following CSE treatment will add to our understanding of the molecular response of the lung alveolar epithelium to cigarette smoke exposure.

A second look at pharmaceutical spending as determinants of health outcomes in Canada

Per capita spending on pharmaceutical products has increased substantially in recent decades in Canada. Recent Canadian research by Crémieux et al. concludes that there is a strong statistical relationship between pharmaceutical spending and health outcomes (Health Econ. 2005a; 14: 117, Health Econ. 2005b; 14(2): 107-116). This paper takes a second look at pharmaceutical spending as determinants of health outcomes in Canada. In doing so, it examines the robustness of the findings of Crémieux et al. by considering the appropriateness of the data used and statistical approach utilized. Particular attention is given to the potential for non-stationarity and spurious regression, issues related to unit heterogeneity and the choice of estimators. In contrast with earlier findings, on the whole, no discernable relationship between spending on private or public pharmaceutical products and infant mortality or life expectancy at 65 is observed.

Current smoking behaviour among rural South African children: Ellisras Longitudinal Study

BACKGROUND

The use of tobacco products is the major cause of chronic diseases morbidity and mortality. Most smokers start the smoking habits from childhood and adolescent stages.

METHOD

This was a cross-sectional study. A total of 1654 subjects (854 boys and 800 girls), aged 11 to 18 years, who were part of the Ellisras Longitudinal Study completed the questionnaire. Association between tobacco products use and habits, attitudes and beliefs were explored in this study. Logistic regression was used to estimate the association.

RESULTS

The prevalence of tobacco product use increases with increasing (4.9 to 17.1%) age among boys whereas girls do not smoke cigarette but only considerable number (1.0 to 4.1%) use home made tobacco products (pipe and snuff) among the Ellisras rural children. Parents and grand parents play a significant (about 50%) role in influencing smoking behaviour among the Ellisras rural children. Seeing actors smoking on TV shows was positively associated (p < 0.05) with smoking (OR = 2.3 95%CI (1.3-4.1 and OR = 2.3 95%CI 1.3-4.1 after adjusting for age and gender). However, women who smoke cigarette were significantly (p < 0.001) associated with success and success and wealth (OR = 2.8, 95% CI 1.5-5.2) even after adjusting for age and gender (OR = 2.9 95% CI 1.5-5.4).

CONCLUSION

The usage of tobacco products was high among older boys. Girls did not smoke cigarette. This tobacco use behaviour mirrors the cultural norms and adult behaviour. The association of this tobacco used products with biological parameters will shed more light on the health of these children over time.

Historical and current perspective on tobacco use and nicotine addiction

Although the addictive influence of tobacco was recognized very early, the modern concepts of nicotine addiction have relied on knowledge of cholinergic neurotransmission and nicotinic acetylcholine receptors (nAChRs). The discovery of the 'receptive substance' by Langley, that would turn out to be nAChRs, and 'Vagusstoff' (acetylcholine) by Loewi, coincided with an exciting time when the concept of chemical synaptic transmission was being formulated. More recently, the application of more powerful techniques and the study of animal models that replicate key features of nicotine dependence have led to important advancements in our understanding of molecular, cellular and systems mechanisms of nicotine addiction. In this review, we present a historical perspective and overview of the research that has led to our present understanding of nicotine addiction.

Adolescent tobacco use and health in Southeast Asia

The use of tobacco by adolescents is a major public health concern worldwide. There are 1.2 billion smokers globally, of which more than 50% are young people. The Southeast Asian countries have about 600 million tobacco smokers within the global burden of tobacco users. Most smokers begin at early stage of life and persist through adulthood. Malaysia alone has about 5 million smokers, 20% of whom are younger than 18 years old. Many factors are implicated in the continuous rising trend of tobacco use among adolescents in Southeast Asia. A triad of family, environmental, and individual factors synergistically acts to motivate adolescents toward smoking. This article discusses the current trends of tobacco use and implications of increasing rise in adolescent smoking in the Southeast Asia region.

Selection and the effect of prenatal smoking

There is a debate about the extent to which the effect of prenatal smoking on infant health outcomes is causal. Poor outcomes could be attributable to mother characteristics, which are correlated with smoking. I examine the importance of selection on the effect of prenatal smoking by using three British cohorts where the mothers' knowledge about the harms of prenatal smoking varied substantially. I find that the effect of smoking on the probability of a low birth weight birth conditional on gestation is slightly more than twice as large in 2000 compared with 1958, implying that selection could explain as much as 50% of the current association between smoking and birth outcomes.

Lung cancer in never smokers: clinical epidemiology and environmental risk factors

More than 161,000 lung cancer deaths are projected to occur in the United States in 2008. Of these, an estimated 10 to 15% will be caused by factors other than active smoking, corresponding to 16,000 to 24,000 deaths annually. Thus lung cancer in never smokers would rank among the most common causes of cancer mortality in the United States if considered as a separate category. Slightly more than half of the lung cancers caused by factors other than active smoking occur in never smokers. As summarized in the accompanying article, lung cancers that occur in never smokers differ from those that occur in smokers in their molecular profile and response to targeted therapy. These recent laboratory and clinical observations highlight the importance of defining the genetic and environmental factors responsible for the development of lung cancer in never smokers. This article summarizes available data on the clinical epidemiology of lung cancer in never smokers, and several environmental risk factors that population-based research has implicated in the etiology of these cancers. Primary factors closely tied to lung cancer in never smokers include exposure to known and suspected carcinogens including radon, second-hand tobacco smoke, and other indoor air pollutants. Several other exposures have been implicated. However, a large fraction of lung cancers occurring in never smokers cannot be definitively associated with established environmental risk factors, highlighting the need for additional epidemiologic research in this area.

Should burden of disease estimates include cannabis use as a risk factor for psychosis?

Louise Degenhardt and colleagues discuss the evidence and the debate about whether Global Burden of Disease estimates should include cannabis use as a risk factor for psychosis.

Smoking-attributable mortality and years of potential life lost in 16 Brazilian capitals, 2003: a prevalence-based study

BACKGROUND

To establish the impact of tobacco smoking on mortality is essential to define and monitor public health interventions in developing countries.

METHODS

The Smoking-Attributable Mortality, Morbidity and Economic Costs (SAMMEC) software was used to estimate the smoking attributable mortality (SAM) in 15 Brazilian State Capitals and the Federal District for the year 2003. Smoking prevalence and mortality data of people aged 35 years or older were obtained for each city from the Brazilian Household Survey on Non Communicable Diseases Risk Factors (2002-2003) and from the Brazilian Mortality System (2003), respectively.

RESULTS

In 2003, of the 177,543 deaths of persons aged 35 years and older 24,222 (13.64%) were attributable to cigarette smoking. This total represents 18.08% of all male deaths (n = 16,896) and 8.71% (n = 7,326) of all female deaths in these cities. The four leading causes of smoking-attributable death were chronic airways obstruction (4,419 deaths), ischemic heart disease (4,417 deaths), lung cancer (3,682 deaths), and cerebrovascular disease (3,202 deaths). Cigarette smoking accounted for 419,935 years of potential life lost (YPLL) (279,990 YPLL for men and 139,945 YPLL for women) in the same period.

CONCLUSION

Tobacco use caused one out of five male deaths and one out of ten female deaths in the sixteen cities in 2003. Four leading causes of smoking attributable deaths (ischemic heart disease, chronic airways obstruction, lung cancer and cerebrovascular disease) accounted for 64.9% of SAM. Effective and comprehensive actions must be taken in order to slow this epidemic in Brazil.

Relatos de caso: seu papel em um periódico médico

Os relatos de casos constituem uma velha tradição na literatura médica e, até o advento de formas mais sofisticadas de estudos, reinaram absolutos como forma de publicação. Apesar de suas qualidades inquestionáveis, os relatos de casos perderam parte de sua importância e prestígio. Alguns periódicos médicos de destaque aceitam relatos de casos apenas sob forma de cartas ao editor ou na versão eletrônica, enquanto outros simplesmente não os aceitam de forma alguma. Esse artigo revisa criticamente os aspectos positivos e negativos dos relatos de casos e sua importância na educação médica. Mesmo em um mundo médico onde a evidência tornou-se obrigatória, relatos de casos ainda desempenham um papel relevante.

Produção científica publicada nos Anais Brasileiros de Dermatologia (2003-2007)

FUNDAMENTOS - A produção científica da dermatologia brasileira, quantitativa e qualitativamente, é pouco conhecida e pouco estudada. OBJETIVO - Analisar características da produção científica da dermatologia brasileira segundo o publicado nos Anais Brasileiros de Dermatologia entre 2003 e 2007. MÉTODOS - Realizou-se estudo transversal através análise dos artigos publicados nas seções de "investigação clínica, epidemiológica, laboratorial e terapêutica"; "caso clínico"e "comunicação"dos Anais Brasileiros de Dermatologia entre 2003 e 2007. As variáveis de interesse foram: objeto temático, delineamento utilizado e grupo de enfermidades nas seções de investigação e caso clínico e o enfoque quanto à seção "comunicação". RESULTADOS - Entre os artigos de investigação predominaram os trabalhos clínicos (60,3%); os com temática cirúrgica ou cosmiátrica somaram 13%. Delineamento descritivo/observacional prevaleceu (81,9%), sendo a "série de casos"o mais utilizado (50%). Predominaram enfermidades infecciosas (33,6%) entre os de investigação e inflamatórias (28,6%) entre os casos relatados. Relato de casos (54,3%) foi o principal enfoque dado às comunicações CONCLUSÃO - Predominou a tradição descritiva nos artigos publicados no período. Delineamentos mais elaborados e sofisticados foram incomuns. O método científico e a análise crítica da literatura devem fazer parte do currículo da pós-graduação em dermatologia, stricto e lato sensu.

Surveillance for health behaviors of American Indians and Alaska Natives-findings from the behavioral risk factor surveillance system, 2000-2006

BACKGROUND

The authors compared estimates for cancer risk factors, use of cancer screening tests, health status indicators, and access to care for American Indians and Alaska Natives (AI/ANs) and non-Hispanic whites (NHWs) in the US and for AI/ANs in 6 Indian Health Service regions.

METHODS

Behavioral Risk Factor Surveillance System data were aggregated from the years 2000 through 2006 and were used to calculate weighted prevalence estimates by gender for key variables except demographic variables.

RESULTS

Compared with NHWs, AI/ANs had lower prevalence estimates for income, educational attainment, insurance coverage, and access to personal healthcare providers. AI/ANs in Alaska and NHWs had similar estimates for diabetes (approximately 6%); however, the prevalence was nearly twice as high among AI/ANs in the other regions. The prevalence of obesity was higher for AI/ANs (29.6%) than for NHWs (20.9%). The prevalence of binge drinking was higher among AI/AN males (24.9%) than among AI/AN females (8.5%). Heavy drinking was more prevalent among NHW females (5.3%) than among AI/AN females (3.5%). AI/ANs were more likely to be current smokers (31.1%) than NHWs (22.8%). The prevalence of AI/ANs who never smoked ranged from 31.5% in Alaska to 56.9% in the Southwest. In 5 of the 6 regions, AI/AN females had lower prevalence estimates of both Papanicolaou and mammography testing than NHW females. The use of colorectal cancer screening tests was more common among NHWs (53.8%) than among AI/ANs (44%).

CONCLUSIONS

Although cancer health disparities persist among AI/ANs, the current analysis indicated that variation in the prevalence of their chronic disease risk factors may be obscured when national data are not examined by smaller geographic areas such as regions.

Genetic and environmental factors in head and neck cancer genesis

Head and neck squamous cell carcinoma (HNSCC) include squamous cell carcinomas of the oral cavity, pharynx, and larynx. Epidemiologic data suggest that the etiology and pathogenesis of HNSCC are influenced by environmental and lifestyle-related factors, such as tobacco use, ethanol consumption, papilloma virus infection, dietary factors and exposure to toxic substances. DNA repair systems and carcinogen-metabolizing enzymes can increase the risk for HNSCC but no definite causal mechanism has been demonstrated. There are several well-characterized entities that are associated with risk and prognosis of head and neck cancer, including Lynch-II syndrome, Bloom syndrome, Fanconi's anemia, xeroderma pigmentosum, ataxia telangiectasia, and Li-Fraumeni syndrome. This review aims to present the current status in our understanding of HNSCC and highlight controversies relating to the role of several factors in the genesis of the cancer.

"Not one single case of throat irritation": misuse of the image of the otolaryngologist in cigarette advertising

Early in the last century, when questions about the health effects of smoking became a topic of widespread discussion, tobacco companies undertook a multi-faceted campaign to allay the public's fears. As terms like "smoker's cough" and "coffin nails" (referring to cigarettes) began to appear in the popular vernacular, tobacco marketers recognized the need to counter this threat to their livelihood. One strategy was to use endorsements by healthy and vigorous-appearing singers, radio stars, and actors. Another was to raise fears over weight gain: "Reach for a Lucky instead of a sweet." Among the more reprehensible tactics was the utilization of the image of the noble and caring physician to sell cigarettes: doctors were depicted both as satisfied and enthusiastic partakers of the smoking habit (e.g., "More doctors smoke Camels"). Images of medical men (and a few token women) appeared under warm reassurances of the safety of smoking. Frequently, images appeared of a head-mirrored "throat doctor," smiling benignly, while indicating that the company's product would do no harm. Indeed, many cigarette ads, especially for menthol brands, suggested a therapeutic soothing benefit from smoking. Liberal use was also made of pseudo-scientific medical reports and surveys. Our intention is to tell, principally through advertising images-the story of how, between the late 1920s and the early 1950s, tobacco companies used deceptive and often patently false claims in an effort to reassure the public of the safety of their products.

The U.S. Food and Drug Administration's evidence-based review for qualified health claims: tomatoes, lycopene, and cancer

Several studies have reported an inverse association between tomato and/or lycopene intake and the risk of some types of cancer. In 2004, the U.S. Food and Drug Administration (FDA) received two petitions for qualified health claims regarding tomatoes, lycopene, and the risk reduction for some forms of cancer. Health claims that characterize the relationship between a food or food component and a disease or health-related condition require premarket approval by FDA to be included on the labels of conventional foods and dietary supplements. Here we describe FDA's review of the scientific data for tomato and/or lycopene intake with respect to risk reduction for certain forms of cancer. The FDA found no credible evidence to support an association between lycopene intake and a reduced risk of prostate, lung, colorectal, gastric, breast, ovarian, endometrial, or pancreatic cancer. The FDA also found no credible evidence for an association between tomato consumption and a reduced risk of lung, colorectal, breast, cervical, or endometrial cancer. The FDA found very limited evidence to support an association between tomato consumption and reduced risks of prostate, ovarian, gastric, and pancreatic cancers.

Smoking trends in Italy from 1950 to 2000

STUDY OBJECTIVE

To assess how the prevalence of smokers in Italy from 1950 to 2000 has changed, in parallel with law development and the growing attention towards smoking prevention.

DESIGN, SETTING, AND PARTICIPANTS

Historical data on smoking trends have been obtained using data collected in 2000 by the National Institute of Statistics. A correction coefficient is proposed to overcome the bias of differential mortality reported in other papers. The sample is made up of 102 261 people aged 15-69 years.

MAIN RESULTS

A general downward trend is seen; there is a more pronounced decrease starting from 1975 to 1980. In both sexes the peak prevalence tends to decrease according to the birth cohort because of the earlier age in which they gave up. A partial exception to the decline of tobacco use in recent years may be made for the 15-19 year-old age group, which has remained stable since 1990.

CONCLUSIONS

Although a comprehensive community programme against tobacco was not developed, the different prevention actions implemented in Italy have contributed to a change in attitude and behaviour. The effect of tobacco control strategies implemented in Italy until now is more evident in relation to the breaking of the smoking habit, which happens at an increasingly younger age, although it is not clear how much it is able to prevent people from starting smoking.

Medical Expenditure of National Health Insurance Attributable to Smoking among the Korean Population

OBJECTIVES

The purpose of this study was to determine the population-attributable risk (PAR) and estimate the total medical expenditure of the Korean National Health Insurance (KNHI) due to smoking.

METHODS

We used data from the Korean Cancer Prevention Study of 1,178,138 Koreans aged 30 to 95. These data were available from 1992 to 2003 and covered a long-term follow-up period among the Korean population.

RESULTS

The total medical expenditure of KNHI related to smoking increased by 27% from $324.9 million in 1999 to $413.7 million in 2003. By specific diseases, smoking-attributable KNHI medical expenditure was the highest for lung cancer ($74.2 million), followed by stroke ($65.3 million), COPD ($50.1 million), CHD ($49 million) and stomach cancer ($30 million). A total of 1.3 million KNHI patients were suffering from smoking-related diseases in 2003. We predicted rises in total KNHI medical expenditure related to smoking to $675.1 million (63% increase compared with that of 2003) and in the total number of KNHI patients suffering from smoking-related diseases to about 2.6 million (an approximate 100% increase compared with those in 2003) in 2015.

CONCLUSIONS

We found a substantial economic burden related to the high smoking prevalence in South Korea.

What is the optimal vitamin D status for health?

The most objectively substantiated health-related reason for tanning is that it improves vitamin D status. The serum 25-hydroxyvitamin D concentration (25(OH)D) is the measure of vitamin D nutrition status. Human biology was probably optimized through natural selection for a sun-rich environment that maintained serum 25(OH)D higher than 100 nmol/L. These levels are now only prevalent in people who spend an above-average amount of time outdoors, with the sun high in the sky. The best-characterized criteria for vitamin D adequacy are based on randomized clinical trials that show fracture prevention and preservation of bone mineral density. Based upon these studies, 25(OH)D concentrations should exceed 75 nmol/L. This concentration is near the upper end of the 25(OH)D reference ("normal") range for populations living in temperate climates, or for people who practice sun-avoidance, or who wear head coverings. Officially mandated nutrition guidelines restrict vitamin D intake from fortified food and supplements to less than 25 mcg/day, a dose objectively shown to raise serum 25(OH)D in adults by about 25 nmol/L. The combined effect of current nutrition guidelines and current sun-avoidance advice is to ensure that adults who follow these recommendations will have 25(OH)D concentrations lower than 75 nmol/L. Therefore, advice to avoid UVB light should be accompanied by encouragement to supplement with vitamin D in an amount that will correct for the nutrient deficit that sun-avoidance will cause.

Tobacco use and non-Hodgkin lymphoma: results from a population-based case-control study in the San Francisco Bay Area, California

OBJECTIVE

Investigate the association between tobacco use and non-Hodgkin lymphoma (NHL).

METHODS

Tobacco-use data were collected during in-person interviews in a population-based case-control study of NHL (N=1593 patients, N=2515 controls) conducted in the San Francisco Bay Area between 1988 and 1995. Odds ratios (ORs) for HIV-negative participants were obtained from adjusted unconditional logistic regression models stratified by sex.

RESULTS

NHL was not associated with overall tobacco use, intensity or duration of cigarette smoking in women or men. However, ORs were increased for NHL among men who used any non-cigarette tobacco alone (OR=1.7), non-cigarette tobacco and cigarettes (OR=1.4), multiple types of non-cigarette tobacco alone (OR=2.1) and smokeless tobacco alone (OR=4.0). In analyses stratified by sex and age, ORs for NHL associated with cigarette smoking in general were above unity among those aged > or =60 years. ORs for follicular lymphoma were increased in men who used cigarettes and other tobacco, cigars alone and smokeless tobacco alone. Diffuse large-cell lymphoma in men was associated with use of cigarettes and other tobacco, and multiple types of non-cigarette tobacco.

CONCLUSION

Our data do not support an association between overall tobacco use and all NHL in women or men. Further analyses are warranted in larger studies to evaluate non-cigarette tobacco use, tobacco-related biologic markers and genetic factors in the development of NHL.

Genetic polymorphism of the CYP1A1, CYP2E1, GSTM1 and GSTT1 genes and lung cancer susceptibility in a north indian population

CYP1A1, CYP2E1, GSTM1 and GSTT1 polymorphisms were evaluated in north Indian lung cancer patients and controls. The estimated relative risk for lung cancer associated with the CYP1A1*2C allele was 2.68. Apart from the CYP1A1*2C genotype, there was no attributable risk in relation to other genotypes when analyzed singly. However, in the presence of a single copy of the variant CYP1A1 (CYP1A1*1/2A) and null GSTT1 genes, there was a three-fold increased risk for lung cancer; when stratified histologically the relative risk increased to 3.7 in case of SQCC. Similarly individuals carrying the mutant CYP1A1*2C genotype and single copy of the variant CYP1A1 Mspl allele, had a relative risk of 2.85 for lung cancer. In case of the GSTM1 and CYP1A1 genotypes, null GSTM1 and variant Msp1 alleles had two-fold elevated risk for SQCC. On the other hand CYP1A1*2C and null GSTM1 genotype had a 3.5-fold elevated risk for SCLC. Stratified analysis indicated a multiplicative interaction between tobacco smoking and variant CYP1A1 genotypes on the risk for SQCC and SCLC. The heavy smokers (BI > 400) with CYP1A1*2C genotype were at a very high risk to develop SCLC with an OR of 29.30 (95% CI = 2.42-355, p = 0.008). Taken together, these findings, the first to be analyzed in north Indian population, suggest that combined GSTT1 , GSTM1 and CYP1A1 polymorphisms could be susceptible to lung cancer induced by bidi (an Indian cigarette) smoking.

Genetic predisposition to cancer - insights from population genetics

Individuals differ in their inherited tendency to develop cancer. Major single-gene defects that cause early cancer onset have been known for many years from their inheritance patterns, and inherited defects that have weaker effects on predisposition were also suspected to exist. Recent progress in cancer genetics has identified specific loci that are involved in cancer progression, many of which have key roles in DNA repair, cell-cycle control and cell-death pathways. Those loci, which are often mutated somatically during cancer progression, sometimes also contain inherited mutations. Recent genetic studies and quantitative population-genetic analyses provide a framework for understanding the frequency of inherited mutations and the consequences of these mutations for increased predisposition to cancer.

Globalization and risks to health

As borders disappear, people and goods are increasingly free to move, creating new challenges to global health. These cannot be met by national governments alone but must be dealt with instead by international organizations and agreements

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.

Lung cancer risk in germline p53 mutation carriers: association between an inherited cancer predisposition, cigarette smoking, and cancer risk

We recently observed a significantly increased risk for lung cancer in carriers of p53 germline mutations. Because cigarette smoking is known to play an important role in increasing the risk for lung cancer in the general population, we wanted to determine the role of cigarette smoking in lung cancer risk in people with a genetic susceptibility based on a p53 germline mutation. We studied 1263 people from 97 families enrolled in a cohort study of families systematically ascertained through childhood soft-tissue sarcoma patients treated at the M.D. Anderson Cancer Center, University of Texas, between 1944 and 1975. We assessed the incidence of lung and smoking-related cancers in 33 carriers of germline p53 mutations and in 1,230 noncarriers to determine whether there was an association between an inherited cancer predisposition, cigarette smoking, and cancer risk. We analyzed the association between cigarette smoking, mutation status, and lung and other smoking-related cancers by the Kaplan-Meier method and the Cox proportional hazards model with adjustments for birth year, race, and sex. In the hazards model, we incorporated a robust variance estimation to adjust for familial correlation. We observed an increased risk of a variety of histological types of lung cancer in the carriers of the p53 germline mutation. Mutation carriers who smoked had a 3.16-fold (95% confidence interval =1.48-6.78) higher risk for lung cancer than the mutation carriers who did not smoke. Our results demonstrate that cigarette smoking significantly increases lung cancer risk in carriers of a germline p53 mutation. This finding could be useful in designing strategies for early detection and treatment of lung and smoking-related cancers in individuals with this inherited cancer predisposition.