Swedish moist snuff and myocardial infarction among men

Dietary habits among snus users: a population-based cross-sectional study

Background

The dietary habits among snus users are largely unknown and have not been accounted for in observational studies on the health effects of snus use.

Aim

To examine whether snus users eat unhealthier than never tobacco users.

Methods

A total of 3,397 male participants, examined between 1994 and 2014 in the Northern Sweden Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA) study, were included. Snus use and dietary habits were self-reported using questionnaires, from which intakes of different food groups, macronutrients, and a healthy diet score (HDS) were calculated (the latter as a proxy for overall diet quality). The association between snus use and dietary habits was examined by quantile regression models.

Results

In the multivariable-adjusted model, current snus users had a lower HDS (median difference: -0.86 [95% confidence interval: -1.32, -0.40]) than never tobacco users. Snus users also consumed fewer weekly servings of fruits and berries (median difference: -1.03 [-1.65, -0.40]), and their estimated percentage of energy intake consisted of less carbohydrates (median difference: -1.43 [-2.12, -0.74]) and of more total fat (median difference: 0.99 [0.30, 1.67]), saturated fat (median difference: 0.67 [0.29, 1.05]), monounsaturated fat (median difference: 0.44 [0.20, 0.68]), trans fat (median difference: 0.03 [0.01, 0.06]), and alcohol (median difference: 0.21 [0.02, 0.40]).

Conclusion

We observed that snus users had an unhealthier diet than never tobacco users. Future studies on the association between snus use and health outcomes should, therefore, consider diet as a potential confounder.

Association of Cardiovascular Disease Risk Factors with Exclusive Smokeless Tobacco Use among US Males: Cross-Sectional Analysis of NHANES Data 2003-2018

PURPOSE

To evaluate cardiovascular disease (CVD) risk factors among smokeless tobacco (ST) users. Exclusive ST users were compared to exclusive cigarette smokers and non-tobacco users.

DESIGN

Cross-sectional study.

SAMPLE

Data were used from 16,336 adult males who participated in one of the National Health and Nutrition Examination Surveys (NHANES) from 2003 to 2018.

MEASURES

Biochemically verified tobacco use, CVD risk factors (hypertension, cholesterol levels, BMI categories), physical activity, cotinine concentration, and sociodemographic variables.

ANALYSIS

Weighted analysis of the aggregate data was performed. ST users were compared with cigarette smokers and nontobacco users for their association with CVD risk factors. Associations were examined using univariate and multiple logistic regression with odds ratios (OR) and 95% confidence intervals (CI) reported.

RESULTS

Prevalence of exclusive ST use was 4.4% whereas, exclusive smoking was 22.2%. Among ST users, 36.2% were hypertensive, 24.5% had high cholesterol levels, and most of them were overweight (31.1%) or obese (52.6%). ST users were more likely to have hypertension compared to smokers (aOR = 1.48, 95%CI: 1.12, 1.95) and nontobacco users (aOR = 1.41, 95%CI: 1.09, 1.83) adjusted for other covariates. ST users were twice more likely to be obese than nontobacco users (aOR = 2.18, 95%CI: 1.52, 3.11). ST users had significantly higher cotinine concentration than smokers.

CONCLUSION

Study findings indicate substantial association of ST use among males with hypertension and obesity which are independent risk factors of CVD.

Review with meta-analysis relating North American, European and Japanese snus or smokeless tobacco use to major smoking-related diseases

BACKGROUND

While extensive information exists relating cigarette smoking to the risk of lung cancer, chronic obstructive pulmonary disease (COPD), ischaemic heart disease (IHD) or acute myocardial infarction (AMI), and stroke, far less information is available on risks from moist snuff (“snus”) or smokeless tobacco (ST) in United States/Canada, Europe or Japan.

AIM

To summarize data from the selected countries on risks of the four diseases associated with current ST or snus use.

METHODS

Publications in English in 1990-2020 were considered that, based on epidemiological studies in North America, Europe or Japan, estimated risks of lung cancer, COPD, IHD/AMI, or stroke according to use of ST or snus. The studies should involve at least 100 cases of the disease considered, and not be restricted to those with specific other diseases. Medline literature searches were conducted, selecting papers initially from examination of titles and abstracts, and then from full texts. Further papers were sought from reference lists in selected papers, reviews and meta-analyses. For each disease, relative risk estimates adjusted at least for age were extracted relating ST or snus use to risk, and combined using random-effects meta-analysis. The estimates were mainly for current vs. never or non-current use, but results for ever vs never use were also considered.

RESULTS

Seven publications reported results for ST use from six United States studies. The most useful results came from four studies which provided results for current vs. never use. Random-effects meta-analyses of these results showed an increased risk for each disease, clearest for lung cancer (relative risk 1.59, 95% confidence interval 1.06-2.39, based on 4 estimates) and COPD (1.57, 1.09-2.26, n = 3), but also significant (at P < 0.05) for IHD (1.26, 1.10-1.45, n = 4) and stroke (1.27, 1.03-1.57, n = 4). Also including results for ever vs. never use from two other studies increased the lung cancer estimate to 1.80 (1.23-2.64, n = 6), but had little effect on the other estimates. For snus, 16 publications described results from 12 studies, one in Norway and the rest in Sweden. There were no results for COPD, and only three for lung cancer, with these reporting a relative risk of 0.80 (0.40-1.30) for current vs never use. More extensive data were available for IHD/AMI and stroke. Using the latest results from each study, combined estimates for current vs. never use were 1.00 (0.91-1.11, n = 5) for IHD/AMI and 1.05 (0.95-1.17, n = 2) for stroke, while for current vs. non-current use they were 1.10 (0.92-1.33, n = 9) for IHD/AMI and 1.12 (0.86-1.45, n = 9) for stroke. Meta-analyses including earlier results from some studies also showed no significant association between snus use and IHD/AMI or stroke. No relevant results were found for Japan.

CONCLUSION

Risks of smoking-related diseases from snus use in Scandinavia are not demonstrated, while those from ST use in the United States are less than from smoking.

Smokeless Tobacco Use and Prevalence of Cardiovascular Disease Among Males in the Population Assessment of Tobacco and Health (PATH) Study, Waves 1–4

•

Oral smokeless tobacco (SLT) products are non-combusted forms of tobacco that can be dependence producing.

•

SLT use may pose health risks to users such as cardiovascular disease (CVD) through various pathways including influencing hemodynamics, endothelial dysfunction, inflammation, insulin resistance, hyperlipidemia, and arrhythmogenesis.

•

Past studies have suggested a small, elevated risk of CVD among SLT users compared to never tobacco users.

•

This study advances the literature by exploring how the duration of regular SLT use relates to CVD prevalence.

•

In this study of ≥ 40-year-old men only, we did not find a consistent dose–response trend for years of SLT use and prevalence of CVD.

The purpose of this period prevalence study is to compare the prevalence of cardiovascular disease (CVD) in current/former established smokeless tobacco (SLT) users (ever SLT users who have used the product fairly regularly) to those who were: 1) never established cigarette smokers and SLT users, and 2) current/former established exclusive cigarette smokers (have smoked at least a 100 or more cigarettes in lifetime) only, adjusting for known risk factors for CVD. Analyses included 4,703 men ≥ 40 years of age who participated in the Population Assessment of Tobacco and Health (PATH) Study, Waves: 1–4, conducted between 2013 and 2017. Current users were those using SLT products daily or on some days, whereas former users had not used SLT and/or cigarettes in the past 12 months. CVD prevalence was defined as a self-reported diagnosis of congestive heart failure, stroke, or myocardial infarction. Among current/former established SLT users, years of use defined exposure history, while pack-years defined exposure history for smokers. Adjusted odds ratios (AOR) and 95% confidence intervals (CI) were reported with trend tests to examine dose–response associations. Current/former established exclusive SLT users were not significantly more likely to have had any CVD compared to never established cigarette and SLT users (OR = 1.7 [0.8–3.7]), or current/former established exclusive cigarette smokers (OR = 0.9 [0.5–1.8]). Current/former established exclusive cigarette smokers were more likely to have had any CVD compared to those who were never established cigarette and SLT users (OR = 1.6 [1.1–2.3]).

Global burden of disease due to smokeless tobacco consumption in adults: an updated analysis of data from 127 countries

BACKGROUND

Smokeless tobacco (ST) is consumed by more than 300 million people worldwide. The distribution, determinants and health risks of ST differ from that of smoking; hence, there is a need to highlight its distinct health impact. We present the latest estimates of the global burden of disease due to ST use.

METHODS

The ST-related disease burden was estimated for all countries reporting its use among adults. Using systematic searches, we first identified country-specific prevalence of ST use in men and women. We then revised our previously published disease risk estimates for oral, pharyngeal and oesophageal cancers and cardiovascular diseases by updating our systematic reviews and meta-analyses of observational studies. The updated country-specific prevalence of ST and disease risk estimates, including data up to 2019, allowed us to revise the population attributable fraction (PAF) for ST for each country. Finally, we estimated the disease burden attributable to ST for each country as a proportion of the DALYs lost and deaths reported in the 2017 Global Burden of Disease study.

RESULTS

ST use in adults was reported in 127 countries; the highest rates of consumption were in South and Southeast Asia. The risk estimates for cancers were also highest in this region. In 2017, at least 2.5 million DALYs and 90,791 lives were lost across the globe due to oral, pharyngeal and oesophageal cancers that can be attributed to ST. Based on risk estimates obtained from the INTERHEART study, over 6 million DALYs and 258,006 lives were lost from ischaemic heart disease that can be attributed to ST. Three-quarters of the ST-related disease burden was among men. Geographically, > 85% of the ST-related burden was in South and Southeast Asia, India accounting for 70%, Pakistan for 7% and Bangladesh for 5% DALYs lost.

CONCLUSIONS

ST is used across the globe and poses a major public health threat predominantly in South and Southeast Asia. While our disease risk estimates are based on a limited evidence of modest quality, the likely ST-related disease burden is substantial. In high-burden countries, ST use needs to be regulated through comprehensive implementation of the World Health Organization Framework Convention for Tobacco Control.

Smoke and Heart Should Stay Apart: A Look at E Cigarettes and Other Alternatives to Conventional Cigarettes, and Their Impact on Cardiovascular Health

The leading cause of preventable death in the world is smoking; leading to 7 million deaths attributable to tobacco use per year worldwide and 480,000 deaths per year in the United States. Though the actual rates of smoking in the United States have been on the decline, the advent of electronic cigarettes (E cigs) in 2007 was met with immense reception especially among the youth. Though initially thought to be a means to facilitate smoking cessation, recent evidence and the E cigs epidemic suggest its implications in significant morbidity and mortality. The other alternatives for conventional tobacco cigarettes have also been implicated in cardiovascular diseases. This manuscript aims to review E cigarettes and other alternatives to conventional cigarettes, and their impact on cardiovascular health. We conducted a Medline search using various combinations of "Cigarettes," "E cigarettes," "Smokeless tobacco," "hookah", and "cardiovascular risk" to identify pivotal trials published before May 10, 2020, for inclusion in this review. Concurrently, major practice guidelines, trial bibliographies, and pertinent reviews were examined to ensure inclusion of relevant trials. A consensus among the authors was used to choose items for narrative inclusion. The following section reviews data from pivotal trials to review the effects of E cigarettes, smokeless tobacco, hookah, nicotine replacement therapy on cardiovascular mortality and morbidity. There are many alternatives to conventional tobacco cigarette smoking, but none can be attributed as absolutely safe from a cardiovascular health perspective. The abundance of evidence regarding its impact on cardiovascular mortality and morbidity does not position it as a safe alternative, but an alternative means of smoking nicotine. The humongous rise in popularity and its gain in favor among the younger population poses a serious threat to the cardiovascular well-being of the exposed. Thus, E cigs and other alternatives of cigarette smoking do impart differing risks in cardiovascular mortality and morbidity, with the possible exception of nicotine replacement therapy.

Risk of Coronary Heart Disease Among Smokeless Tobacco Users: Results of Systematic Review and Meta-Analysis of Global Data

Background

Use of smokeless tobacco (SLT) products has been linked to multiple adverse effects, especially precancer and cancer of oral cavity. However, the association of SLT use with risk of coronary heart disease (CHD) is shrouded with controversy due to conflicting results in the literature. The present meta-analysis aimed to evaluate the risk of CHD among adult ever-users of SLT products along with sub-group analysis.

Methods

The analysis included studies retrieved from a systematic literature search for published articles assessing risk of CHD with SLT use. Two authors independently extracted risk estimates and study characteristics of the included studies. Summary relative risks were estimated using the random-effect model.

Results

Twenty studies from four WHO regions were included in the analysis. The summary risk of CHD in SLT users was not significantly positive (1.05, 95% CI = 0.96 to 1.15) although a higher risk of fatal CHD was seen (1.10, 95% CI = 1.00 to 1.20). The risk was significant for users in European Region (1.30, 95% CI = 1.14 to 1.47). The results remained unchanged even after strict adjustment for smoking. Product-wise analysis revealed a significant positive association of fatal CHD with snus/snuff use (1.37, 95% CI = 1.14 to 1.61). The SLT-attributable fraction of fatal CHD was calculated to be 0.3%, highest being for European region (5%).

Conclusion

A significant positive association was detected between SLT use and risk of fatal CHD, especially for European users and those consuming snus/snuff. In view of the positive association even after strict adjustment for smoking, these results underscore the need for inclusion of cessation efforts for smokeless tobacco in addition to smoking for control of fatal cardiovascular diseases.

Implications

The present meta-analysis demonstrates a global perspective of association between coronary heart disease (CHD) and use of smokeless tobacco (SLT), especially for fatal cardiac events, even with strict adjustment for smoking. There appears to be some difference in this effect based on the type of SLT product used. These results highlight the independent deleterious effect of SLT products on the outcome of CHD and might help to resolve the long-standing controversy regarding the association of SLT with the risk of CHD. Hence, we propose that in addition to smoking, cessation efforts should be directed towards SLT products as well, for control of cardiovascular diseases.

Systemic Toxicity of Smokeless Tobacco Products in Mice

Introduction

Smokeless tobacco products such as snuff and snus are used worldwide. However, little is known about the systemic and cardiovascular toxicity of smokeless tobacco exposure.

Methods

Biomarkers of endothelial activation and injury, immune functions, platelet activation and insulin resistance were measured in 8-week old male C57BL/6 mice exposed to commercial snuff, CRP-2 reference snuff, commercial snus, CRP-1 reference snus, and nicotine in drinking water (100 µg/mL) for 4, 12, and 24 weeks.

Results

Twenty-four weeks of exposure to smokeless tobacco products or nicotine significantly decreased the levels of circulating Flk+/Sca+ endothelial progenitor cells. Twelve and 24 weeks of exposure to all the smokeless tobacco products and nicotine significantly decreased the levels of circulating CD19+ B cells, CD4+ T cells, CD8+ T cells, and CD11b+ monocytes, whereas 4 weeks of exposure to Camel snus and Copenhagen snuff significantly depleted the levels of peripheral blood CD19+ B cells and CD11b+ monocytes. Twenty-four weeks of exposure to smokeless tobacco products or nicotine significantly decreased plasma IFNγ levels. However, plasma TNFα levels were significantly increased in mice exposed to Copenhagen snuff or nicotine for 24 weeks. This was accompanied by a five to sevenfold increase in the hepatic expression of TNFα. Neither smokeless products nor nicotine affected plasma lipoproteins, platelet activation, or systemic insulin sensitivity.

Conclusions

Chronic exposure to snuff and snus suppresses circulating levels of EPCs, endothelial microparticles and immune cells, but increases plasma TNF-α levels. These effects of smokeless tobacco products are attributable, at least in part, to nicotine.

Implications

Exposure to smokeless tobacco products results in the depletion of endothelial progenitor cells, which may impair the endothelium repair. Suppression of the circulating levels of immune cells upon exposure to smokeless tobacco products may increase the susceptibility to secondary infection. Increased formation of proinflammatory cytokines such as TNFα by nicotine or Copenhagen snuff may lead to vascular inflammation and thereby exacerbate atherogenesis.

Snus: a compelling harm reduction alternative to cigarettes

Snus is an oral smokeless tobacco product which is usually placed behind the upper lip, either in a loose form or in portioned sachets, and is primarily used in Sweden and Norway. The purpose of this review is to examine the reported effects of snus use in relation to specified health effects, namely lung cancer, cardiovascular disease, pancreatic cancer, diabetes, oral cancer and non-neoplastic oral disease. The review also examines the harm reduction potential of snus as an alternative to cigarettes by comparing the prevalence of snus use and cigarette smoking, and the reported incidence of tobacco-related diseases across European Union countries. The scientific literature generally indicates that the use of snus is not a significant risk factor for developing lung cancer, cardiovascular disease, pancreatic cancer or oral cancer. Studies investigating snus use and diabetes have reported that high consumption of snus (estimated as being four or more cans per week) may be associated with a higher risk of developing diabetes or components of metabolic syndrome; however, overall results are not conclusive. Snus use is associated with the presence of non-neoplastic oral mucosal lesions which are reported to heal rapidly once use has stopped. The most recent Eurobarometer data from 2017 reported that Sweden had the lowest prevalence of daily cigarette use in the European Union at 5% whilst daily "oral tobacco" use was reported to be 20%. European data published by the World Health Organisation in 2018 indicated that Sweden had the lowest rate of tobacco-related mortality and the lowest incidence of male lung cancer. Overall, prevalence statistics and epidemiological data indicate that the use of snus confers a significant harm reduction benefit which is reflected in the comparatively low levels of tobacco-related disease in Sweden when compared with the rest of Europe. The available scientific data, including long-term population studies conducted by independent bodies, demonstrates that the health risks associated with snus are considerably lower than those associated with cigarette smoking.

Electronic cigarettes and cardiovascular health: what do we know so far?

While tobacco cigarette (TC) smoking has continued to drop to all-time lows, the use of electronic cigarettes (ECs), introduced in the US in 2007, has been rising dramatically, especially among youth. In EC emissions, nicotine is the major biologically active element, while levels of carcinogens and harmful combustion products that typify TC smoke are very low or even undetectable. TCs cause cardiovascular harm by activation of inflammatory pathways and oxidative damage, leading to atherogenesis and thrombosis, as well as through sympathetic activation triggering ischemia and arrhythmia. While ECs are generally believed to be safer than TCs, there remain many uncertainties regarding the overall cardiovascular health effects of EC usage. In this review, we discuss the various components of EC smoke and review the potential mechanisms of cardiovascular injury caused by EC use. We also discuss the controversy regarding the increasing epidemic of youth EC use weighed against the use of ECs as a smoking-cessation aid.

Smokeless tobacco use and circulatory disease risk: a systematic review and meta-analysis

Objective

Smokeless tobacco use is a public health issue throughout the world, but reviews and analyses of circulatory disease risks associated with smokeless tobacco use may be outdated or incomplete. This study provides a thorough and comprehensive review and meta-analysis of circulatory disease risks in high-income countries, including recently published study estimates.

Methods

We conducted a systematic review of studies of circulatory disease risks associated with smokeless tobacco use in Europe and North America that were identified from electronic databases and reference lists. Study estimates were extracted by region, smokeless tobacco use status, cigarette smoking status, and circulatory condition and combined in meta-analysis using a random-effects model. We used the Newcastle-Ottawa scale to assess study quality and risk of bias.

Results

We identified 17 relevant cohort studies, two pooled analyses, five case-control studies and one cross-sectional analysis. We found increased risk of heart disease (relative risk (RR) 1.17, 95% CI 1.09 to 1.27) and stroke (RR 1.28, 95% CI 1.01 to 1.62) among US smokeless tobacco users compared with non-users. Increased circulatory disease risk was not observed among Swedish smokeless tobacco users.

Conclusion

US smokeless tobacco users were found to have increased risk of heart disease and stroke.

A systematic review on association between smokeless tobacco & cardiovascular diseases

BACKGROUND & OBJECTIVES

The association of smokeless tobacco (SLT) with cardiovascular diseases has remained controversial due to conflicting reports from various countries. Earlier meta-analyses have shown significantly higher risk of fatal myocardial infarction and stroke in SLT users. However, the risk of hypertension (HTN) with SLT products has not been reviewed earlier. This systematic review was undertaken to summarize the evidence available from global literature on the association of SLT with cardiovascular outcomes - heart disease, stroke and HTN.

METHODS

A systematic literature search was performed in PubMed and Google Scholar since their inception till October 2017 using pre-decided search terms and inclusion/exclusion criteria. Data were extracted from studies included independently by two authors and reviewed.

RESULTS

The review included 50 studies - 23 on heart disease, 14 on stroke and 14 on HTN. Majority of the studies evaluating heart disease or stroke were conducted in the European Region and most of these did not find a significant association between SLT use and either of these outcomes. On the other hand, 70 per cent of the studies on HTN were reported from South-East Asian Region and about half of the studies found a higher risk of HTN in SLT users.

INTERPRETATION & CONCLUSIONS

Current available evidence is insufficient to conclusively support the association of cardiovascular diseases with SLT use due to variability in results and methodological constraints in most of the studies. Region and product-specific well-designed studies are required to provide this evidence to the policymakers. However, advice on cessation of SLT products should be offered to patients presenting with cardiovascular diseases.

Targeted plasma proteomics identifies a novel, robust association between cornulin and Swedish moist snuff

Lifestyle behaviors are believed to influence the body’s inflammatory state. Chronic low-grade inflammation contributes to the development of major non-communicable diseases such as diabetes, cardiovascular disease and cancer. Inflammation may thus be an important link between lifestyle and disease. We evaluated self-reported physical activity, tobacco use and alcohol consumption in relation to plasma levels of 160 validated inflammatory and cancer biomarkers. The study included 138 participants from a population-based cohort, all with repeated sampling of plasma and data ten years apart, allowing consideration of both intra- and inter-individual variation. Of 17 relationships identified, the strongest was an independent, positive association between cornulin (CRNN) and Swedish moist snuff (snus) use. We replicated the finding in a second cohort of 501 individuals, in which a dose-response relationship was also observed. Snus explained approximately one fifth of the variance in CRNN levels in both sample sets (18% and 23%). In conclusion, we identified a novel, independent, dose-dependent association between CRNN and snus use. Further study is warranted, to evaluate the performance of CRNN as a potential snus biomarker. The putative importance of lifestyle behaviors on a wide range of protein biomarkers illustrates the need for more personalized biomarker cut-offs.

The relationship of snus use to diabetes and allied conditions

A recent meta-analysis reported smoking to be associated with a 37% higher risk of type 2 diabetes in current smokers, rising to a 57% increase in heavy smokers, which declines on quitting. If the increase results from nicotine exposure, it is possible that using Swedish moist snuff ("snus"), which provides at least equivalent nicotine doses, might also increase diabetes risk. Following a recent publication reporting pooled results from five cohorts, we present a detailed meta-analysis of data from 18 studies. Based on covariate-adjusted estimates, no significant increased risk was seen in never smokers with RRs (95% CIs) of 1.08 (0.86-1.34), 0.93 (0.79-1.11) and 1.05 (0.94-1.18) for current, former and ever snus users. Significant increases were also not seen in the whole population, the corresponding RR estimates being 1.18 (0.94-1.48), 0.69 (0.49-0.96) and 0.95 (0.81-1.11). Nor was there an association of snus use with related endpoints, such as impaired glucose tolerance. However, dose-response analyses showed a relationship, with the highest levels of snus exposure associated with a diabetes RR of 1.65 (1.25-2.18) in never smokers. The evidence relating snus to type 2 diabetes is somewhat limited, requiring further studies to confirm any possible relationship.

Snus use during the life-course and risk of the metabolic syndrome and its components

Objective: We aimed to investigate the association between life-course exposure to snus and prevalence of the metabolic syndrome and its components in adulthood. Design and method: Tobacco habits at baseline (age 16) and three follow-ups (ages 21, 30 and 43) were assessed among 880 participants in a population-based cohort in Northern Sweden. Presence of the metabolic syndrome at age 43 was ascertained using the International Diabetes Federation criteria. Odds ratios and CIs for risk of the metabolic syndrome and its components by snus use at 16, 21, 30 and 43 years were calculated using logistic regression. Cumulative snus use was defined as number of life periods (1–4) with current snus use. Results: At age 43, 164 participants (18.6%) were current snus users. We found no association between exclusive snus use at the ages of 16, 21, 30 and 43 years and the metabolic syndrome at age 43 years. Snus use (among non-smokers) was associated with raised triglycerides and high blood pressure in crude analysis, but not in multivariable models. There was no association between cumulative snus use and risk of the metabolic syndrome. Cumulative snus use was associated with central obesity, raised triglycerides and impaired fasting glucose/diabetes mellitus type 2 in crude analyses, but not after adjustments. Conclusions: The health consequences of snus exposure from adolescence to mid-adulthood do not seem to include increased risk of the metabolic syndrome or its components. The cardio-metabolic risk of dual exposure to snus and cigarettes may warrant further attention.

Contribution of Swedish moist snuff to the metabolic syndrome: A wolf in sheep's clothing?

Aim: Combined effects of genetic and environmental factors underlie the clustering of cardiovascular risk factors in the metabolic syndrome (MetSy). The aim was to investigate associations between several lifestyle factors and MetSy, with a focus on the possible role of smokeless tobacco in the form of Swedish moist snuff (snus). Methods: A population-based longitudinal cohort study within the Västerbotten Intervention Programme in Northern Sweden. All inhabitants at the ages of 30, 40, 50, and 60 are invited to participate in a health survey that includes a questionnaire on psychosocial conditions and lifestyle and measurement of biological variables. Individuals examined in 1990—94 (n=24,230) and who also returned for follow-up after 10 years were included (total of 16,492 individuals: 46.6% men and 53.4% women). Regression analyses were performed. MetSy was the outcome and analyses were adjusted for age, sex, alcohol abuse, and family history of CVD and diabetes. Results: Ten-year development of MetSy was associated with high-dose consumption of snus at baseline (OR 1.6 [95% CI 1.26—2.15]), low education (2.2 [1.92—2.63]), physical inactivity (1.5 [1.22—1.73]) and former smoking (1.2 [1.06—1.38]). Snus was associated with separate components of MetSy, including triglycerides (1.6, 1.30—1.95), obesity (1.7 [1.36—2.18]) but not hypertension, dysglycemia and low HDL cholesterol. Conclusions: MetSy is independently associated with high consumption of snus, even when controlling for smoking status. The finding is of public health interest in societies with widespread use of snus. More research is needed to better understand the mechanisms underlying this effect.

Is moist snuff use associated with excess risk of IHD or stroke? A longitudinal follow-up of snuff users in Sweden

Background: The potential risks of Swedish moist snuff (snus) are debated and studies have shown diverging results. Aims: The aim of this study is to investigate whether there is any excess risk of ischaemic heart disease (IHD) and stroke from snuff use. Methods: The Swedish Survey of Living Conditions from 1988—89 was record-linked to the Swedish Cause of Death Register and the Swedish Hospital Discharge Register to investigate excess mortality and hospitalization from IHD and stroke. A Poisson regression model was used and incidence rate ratios (IRRs) for snuff and smoking were calculated controlling for age, physical activity, self-reported health, number of longstanding illnesses, residential area, and socioeconomic position. Results: Among snuff users there were no excess risks of mortality or hospitalization from IHD (IRR 0.8; 0.5—1.2,) or stroke (IRR 1.1; 0.7—1.8), but, as expected, clear excess risks were found for smokers (IRR 1.7; 1.4—2.1 for IHD, and IRR 1.4; 1.0—1.9 for stroke). Conclusions: This study has not shown any excess risk among users of snuff for IHD or stroke. If there is a risk associated with snuff it is evidently much lower than those associated with smoking.

Smokeless tobacco and coronary heart disease: a 12-year follow-up study

Background Cigarette smoking has declined whereas the use of smokeless tobacco is increasing. There is an ongoing debate as to whether smokeless tobacco is a recommendable strategy to help smokers to quit. However, very few studies have examined the association between smokeless tobacco, namely snuff, and coronary heart disease, which implies that it has not been possible to provide scientific results for public health policies and clinical guidelines concerning the use of smokeless tobacco.

Design A follow-up study.

Methods A random sample of 3120 healthy men aged 30–74 years was interviewed in 1988 and 1989 and followed up to the year 2000 with regard to coronary heart disease. Cox regression was used to estimate the relative risk of coronary heart disease in six categories of smoking and snuffing habits, after adjustment for established risk factors for coronary heart disease.

Results Smokers, former smokers, and those who combined smoking and snuffing had significantly higher hazard ratios than never-smokers. The very highest hazard ratio was found among individuals combining smoking and snuffing. Daily snuffers had a hazard ratio of 1.62 (95% confidence interval 0.70–3.03) after adjustment for age.

Conclusions Even though the association between daily snuffing and coronary heart disease was non-significant, the hazard ratio was markedly increased. Therefore, smokers should not use smokeless tobacco in order to quit smoking, especially as safer alternatives are available. Further studies in different settings are required to provide scientific results for public health policies and clinical guidelines.

Non-Smoking Tobacco Affects Endothelial Function in Healthy Men in One of the Largest Health Studies Ever Performed; The Nord-Trøndelag Health Study in Norway; HUNT3

BACKGROUND

Oral tobacco (snuff) is taking a large market share in Scandinavia, especially with young users. However, long-term health effects are unknown. Small studies show association between snuff and reduced endothelial function, representing an early stage of vascular injury that often precedes manifest cardiovascular disease by several years. We therefore determined the associations between snuff and endothelial function in a large sample of healthy Norwegian men.

METHODS AND DESIGN

In the Fitness substudy of the Nord-Trøndelag Health Study (HUNT3), endothelial function was measured by flow-mediated dilation (FMD). Aerobic fitness was measured by peak oxygen uptake (VO2peak). A cross-sectional design including 1 592 self-reported healthy men compared these observations with records of present tobacco use, standard cardiovascular risk factors, and socioeconomic status, using general linear models.

RESULTS

FMD was lower in snuff users (FMD: 4.12%, 3.63, 4.61) compared to non-users (FMD: 4.52%, 4.27, 4.78) after adjustment for age (difference: -0.57%, -1.12, -0.01). After further adjustment for potential confounders, FMD still tended to be lower in snuff users than in non-users (difference: -0.53%, -1.09, 0.02). This difference was even more pronounced in the inactive snuff users (-0.83%, -1.59, -0.06) and in the low fit snuff users (-0.74%, CI -0.55, 0.079).

CONCLUSIONS

Oral tobacco is associated with a tendency towards reduced endothelial function, indicating vascular changes that precede cardiovascular disease. The strongest associations were found in men with low physical activity or reduced aerobic fitness.

Differences in cardiovascular toxicities associated with cigarette smoking and snuff use revealed using novel zebrafish models

Tobacco use is strongly associated with cardiovascular disease and the only avoidable risk factor associated with development of aortic aneurysm. While smoking is the most common form of tobacco use, snuff and other oral tobacco products are gaining popularity, but research on potentially toxic effects of oral tobacco use has not kept pace with the increase in its use. Here, we demonstrate that cigarette smoke and snuff extracts are highly toxic to developing zebrafish embryos. Exposure to such extracts led to a palette of toxic effects including early embryonic mortality, developmental delay, cerebral hemorrhages, defects in lymphatics development and ventricular function, and aneurysm development. Both cigarette smoke and snuff were more toxic than pure nicotine, indicating that other compounds in these products are also associated with toxicity. While some toxicities were found following exposure to both types of tobacco product, other toxicities, including developmental delay and aneurysm development, were specifically observed in the snuff extract group, whereas cerebral hemorrhages were only found in the group exposed to cigarette smoke extract. These findings deepen our understanding of the pathogenic effects of cigarette smoking and snuff use on the cardiovascular system and illustrate the benefits of using zebrafish to study mechanisms involved in aneurysm development.

Global burden of disease due to smokeless tobacco consumption in adults: analysis of data from 113 countries

BACKGROUND

Smokeless tobacco is consumed in most countries in the world. In view of its widespread use and increasing awareness of the associated risks, there is a need for a detailed assessment of its impact on health. We present the first global estimates of the burden of disease due to consumption of smokeless tobacco by adults.

METHODS

The burden attributable to smokeless tobacco use in adults was estimated as a proportion of the disability-adjusted life-years (DALYs) lost and deaths reported in the 2010 Global Burden of Disease study. We used the comparative risk assessment method, which evaluates changes in population health that result from modifying a population's exposure to a risk factor. Population exposure was extrapolated from country-specific prevalence of smokeless tobacco consumption, and changes in population health were estimated using disease-specific risk estimates (relative risks/odds ratios) associated with it. Country-specific prevalence estimates were obtained through systematically searching for all relevant studies. Disease-specific risks were estimated by conducting systematic reviews and meta-analyses based on epidemiological studies.

RESULTS

We found adult smokeless tobacco consumption figures for 115 countries and estimated burden of disease figures for 113 of these countries. Our estimates indicate that in 2010, smokeless tobacco use led to 1.7 million DALYs lost and 62,283 deaths due to cancers of mouth, pharynx and oesophagus and, based on data from the benchmark 52 country INTERHEART study, 4.7 million DALYs lost and 204,309 deaths from ischaemic heart disease. Over 85 % of this burden was in South-East Asia.

CONCLUSIONS

Smokeless tobacco results in considerable, potentially preventable, global morbidity and mortality from cancer; estimates in relation to ischaemic heart disease need to be interpreted with more caution, but nonetheless suggest that the likely burden of disease is also substantial. The World Health Organization needs to consider incorporating regulation of smokeless tobacco into its Framework Convention for Tobacco Control.

Study of cardiovascular disease biomarkers among tobacco consumers, part 2: biomarkers of biological effect

An age-stratified, cross-sectional study was conducted in the US among healthy adult male cigarette smokers, moist snuff consumers, and non-tobacco consumers to evaluate cardiovascular biomarkers of biological effect (BoBE). Physiological assessments included flow-mediated dilation, ankle-brachial index, carotid intima-media thickness and expired carbon monoxide. Approximately one-half of the measured serum BoBE showed statistically significant differences; IL-12(p70), sICAM-1 and IL-8 were the BoBE that best differentiated among the three groups. A significant difference in ABI was observed between the cigarette smokers and non-tobacco consumer groups. Significant group and age effect differences in select biomarkers were identified.

Tobacco use pattern among a national firefighter cohort

INTRODUCTION

To date, there have been no large-scale, national epidemiological studies of tobacco use patterns among firefighters, particularly with a focus on smokeless tobacco (SLT) and dual use with cigarettes. While rates of firefighters' smoking are relatively low compared to the general population, SLT use typically is substantially higher than the populations they protect. In the current study, we systemically examine tobacco use, including SLT and dual use, and the health-related profiles of various tobacco use groups in a national sample of career firefighters.

METHODS

Data are from a national cohort study of career departments (N = 20) comprised of 947 male firefighters.

RESULTS

Among 947 participants, 197 (21%) were tobacco users, of which, 34.5% used cigarettes, 53.2% used SLT, and 12.2% used both cigarettes and SLT. Adjusted rates of smoking, SLT use, and dual use were 13.2%, 10.5%, and 12.2%, respectively. Tobacco users of all types were significantly younger and had served fewer years in fire service and were significantly more likely to engage in heavy and binge drinking, as well as more likely to show signs of depressive symptoms compared to nontobacco users.

CONCLUSIONS

Detailed information on tobacco use pattern will aid in better understanding what factors are contributing to the high rates of SLT and dual use among firefighters in order to guide and develop an appropriate treatment program for the fire service.

Snus (Swedish smokeless tobacco) use and risk of stroke: pooled analyses of incidence and survival

BACKGROUND

Snus is a moist smokeless tobacco product with high nicotine content. Its use has a short-term effect on the cardiovascular system, but the relationship between snus use and stroke is unclear.

OBJECTIVE

The aim of this study was to assess the associations between use of snus and incidence of and survival after stroke, both overall and according to subtypes.

METHODS

Pooled analyses of eight Swedish prospective cohort studies were conducted, including 130 485 men who never smoked. We estimated hazard ratios (HRs) with 95% confidence intervals (CIs) of incidence and death after diagnosis using Cox proportional hazard regression models and case fatality and survival using logistic regression and Kaplan-Meier methods, respectively.

RESULTS

No associations were observed between the use of snus and the risk of overall stroke (HR 1.04, 95% CI 0.92-1.17) or of any of the stroke subtypes. The odds ratio (OR) of 28-day case fatality was 1.42 (95% CI 0.99-2.04) amongst users of snus who had experienced a stroke, and the HR of death during the follow-up period was 1.32 (95% CI 1.08-1.61).

CONCLUSION

Use of snus was not associated with the risk of stroke. Hence, nicotine is unlikely to contribute importantly to the pathophysiology of stroke. However, case fatality was increased in snus users, compared with nonusers, but further studies are needed to determine any possible causal mechanisms.

Discontinuation of smokeless tobacco and mortality risk after myocardial infarction

BACKGROUND

Given the indications of increased risk for fatal myocardial infarction (MI) in people who use snus, a moist smokeless tobacco product, we hypothesized that discontinuation of snus use after an MI would reduce mortality risk.

METHODS AND RESULTS

All patients who were admitted to coronary care units for an MI in Sweden between 2005 and 2009 and were <75 years of age underwent a structured examination 2 months after discharge (the baseline of the present study). We investigated the risk of mortality in post-MI snus quitters (n=675) relative to post-MI continuing snus users (n=1799) using Cox proportional hazards analyses. During follow-up (mean 2.1 years), 83 participants died. The mortality rate was 9.7 (95% confidence interval, 5.7-16.3) per 1000 person-years at risk in post-MI snus quitters and 18.7 (14.8-23.6) per 1000 person-years at risk in post-MI continuing snus users. After adjustment for age and sex, post-MI snus quitters had half the mortality risk of post-MI continuing snus users (hazard ratio, 0.51; 95% confidence interval, 0.29-0.91). In a multivariable-adjusted model, the hazard ratio was 0.57 (95% confidence interval, 0.32-1.02). The corresponding estimate for people who quit smoking after MI versus post-MI continuing smokers was 0.54 (95% confidence interval, 0.42-0.69).

CONCLUSIONS

In this study, discontinuation of snus use after an MI was associated with a nearly halved mortality risk, similar to the benefit associated with smoking cessation. These observations suggest that the use of snus after MI should be discouraged.

Health risks related to dual use of cigarettes and snus - a systematic review

Reviews show that using snus (Swedish-type moist snuff) is much safer than smoking, with no increased risk from snus of cancer or circulatory disease yet demonstrated, but have not investigated possible health effects from dual use of cigarettes and snus. This review considers studies where health risks can be compared in dual users, those who only use snus or only smoke, and those who use neither product. The interaction RR, the ratio of RRs associated with snus use in smokers and in non-smokers, was used to test for special effects of dual use. Of 51 interaction RRs presented, only one (for gestational hypertension in a study based on the Swedish Medical Register) was significantly (p<0.05) above 1.0, and RRs below 1.0 were commoner, perhaps as cigarette consumption is lower in dual users than those who only smoke. Dual users more often initiate tobacco use with cigarettes than snus. Dual use is much commoner in adolescents than adults, possibly because many tobacco users try both products, eventually settling on one. Epidemiological evidence from various sources, though suffering from weaknesses, consistently suggests concomitant snus use increases smoking quit rates, and aligns with evidence from RCTs using snus to aid smoking cessation.

Epidemiological evidence relating snus to health--an updated review based on recent publications

An earlier review summarized evidence relating use of snus (Swedish-type moist snuff) to health and to initiation and cessation of smoking. This update considers the effect recent publications on snus use and health have on the overall evidence. The additional evidence extends the list of neoplastic conditions unassociated with snus use (oropharynx, oesophagus, stomach, lung) to include colorectal cancer and acoustic neuroma, and further undermines the weakly-based argument that snus use increases the risk of pancreatic cancer, although there is a report of poorer cancer survival in users. It remains undemonstrated that “snuff-dipper’s lesion” increases risk of oral cancer, and recent publications add to the evidence that snus use has no effect on periodontitis or dental caries. Although onset of acute myocardial infarction is not adversely associated with snus use, there is some evidence of an association with reduced survival. Whether this is a direct effect of snus use or a result of confounding by socioeconomic status or other factors requires further investigation, as does a report of an increased risk of heart failure in snus users. Even if some adverse health effects of snus use do exist, it remains clear that they are far less than those of smoking.

Snus use and cardiovascular risk factors in the general population: the HUNT3 study

BACKGROUND AND AIMS

Snus, a form of smokeless tobacco, is increasingly popular in its traditional Nordic markets, and was recently launched commercially in the United States. We examined the cross-sectional associations between snus use and cardiovascular risk factors, and compared them with the corresponding associations of smoking.

DESIGN

Cross-sectional study.

SETTING

The HUNT3 general population survey, Nord-Trøndelag, Norway (2006-08).

PARTICIPANTS

A general population sample of n = 25 163.

MEASUREMENTS

Measured triglyceride,- glucose- and high-density lipoprotein (HDL)-cholesterol levels, blood pressure and waist circumference, registry information on gender, age and education level, self-reported snus use, smoking, physical exercise and alcohol use.

FINDINGS

In age- and gender-adjusted linear regression analyses, extensive snus use was associated with larger waist circumference (b = 1.65, 95% CI = 0.86, 2.43) and higher systolic blood pressure (b = 2.58, 95% CI = 1.48, 3.68), but with higher rather than lower levels of HDL-cholesterol (b = 1.66, 95% CI = 0.79, 2.53). These three differences remained significant after additional adjustment for smoking, education level, physical exercise and alcohol use. Smokers had higher triglyceride and lower HDL-cholesterol than snus users, but lower systolic blood pressure.

CONCLUSIONS

After adjusting statistically for major confounding variables, Norwegians who use snus extensively have a mixed profile in terms of cardiovascular risk: slightly higher waist circumference and systolic blood pressure but also higher high-density lipoprotein-cholesterol.

The effect on health of switching from cigarettes to snus - a review

Interest in snus (Swedish type moist snuff) as an alternative to smoking is increasing, but the evidence on the health effects of switching from cigarettes to snus has not previously been reviewed. We identified six epidemiological cohort or case-control studies, all from Sweden, which allowed comparison of cancer or cardiovascular disease risk in current snus users who formerly smoked ("switchers") with that of never snus users who continued to smoke ("continuers") or of never snus users who quit smoking ("quitters"). Based on 13 sets of comparisons, one for oral cancer, one for stomach cancer and 11 for various cardiovascular disease endpoints, switchers were consistently found to have a lower risk than continuers, with relative risks varying from 0.35 to 0.61, and a similar risk to quitters. Based on estimates from four studies for ischaemic/coronary heart disease or acute myocardial infarction, meta-analyses gave combined relative risk estimates of 0.55 (95% confidence interval 0.45-0.68) for switchers vs. continuers and 1.02 (95% confidence interval 0.83-1.26) for switchers vs. quitters. Though based on limited evidence with some weaknesses, these results are consistent with a recent review which found no increased risk of cancer or heart disease from snus use.

Use of snus and acute myocardial infarction: pooled analysis of eight prospective observational studies

The use of snus (also referred to as Scandinavian or Swedish moist smokeless tobacco), which is common in Sweden and increasing elsewhere, is receiving increasing attention since considered a tobacco smoke "potential reduction exposure product". Snus delivers a high dose of nicotine with possible hemodynamic effects, but its impact on cardiovascular morbidity and mortality is uncertain. The aim of this study was to investigate whether snus use is associated with risk of and survival after acute myocardial infarction (AMI). Data from eight prospective cohort studies set in Sweden was pooled and reanalysed. The relative risk of first time AMI and 28-day case-fatality was calculated for 130,361 men who never smoked. During 2,262,333 person-years of follow-up, 3,390 incident events of AMI were identified. Current snus use was not associated with risk of AMI (pooled multivariable hazard ratio 1.04, 95 % confidence interval 0.93 to 1.17). The short-term case fatality rate appeared increased in snus users (odds ratio 1.28, 95 % confidence interval 0.99 to 1.68). This study does not support any association between use of snus and development of AMI. Hence, toxic components other than nicotine appear implicated in the pathophysiology of smoking related ischemic heart disease. Case fatality after AMI is seemingly increased among snus users, but this relationship may be due to confounding by socioeconomic or life style factors.

Acute Myocardial Infarction in a Young Adult Male Associated with the use of Smokeless Tobacco (Sweka)

Dipping smokeless tobacco (ST) is used worldwide. We report a case of acute myocardial infarction in a young patient, who consumed smokeless tobacco (Sweka) for over one year. ST may be as harmful as smoking and carries adverse cardiac complications. A prompt call for restriction and prohibition is advised and its alternative use to quit smoking must be abandoned.

Is there any association between use of smokeless tobacco products and coronary heart disease in Bangladesh?

BACKGROUND

Most epidemiological studies exploring the association between smokeless tobacco (SLT) use and coronary heart disease (CHD) have been in Western populations, and have focused on SLT products used in those countries. Few studies come from South Asian countries. Our objective was to determine the association between SLT use and CHD among non-smoking adults in Bangladesh.

METHODS

A matched case-control study of non-smoking Bangladeshi adults aged 40-75 years was conducted in 2010. Incident cases of CHD were selected from two cardiac hospitals. Community controls, matched to CHD cases, were selected from neighbourhoods, and hospital controls were selected from outpatient departments of the same hospitals. The Rose Angina Questionnaire (RAQ) was also used to re-classify cases and controls.

RESULTS

The study enrolled 302 cases, 1,208 community controls and 302 hospital controls. Current use was higher among community controls (38%) compared to cases (33%) and hospital controls (32%). Current use of SLT was not significantly associated with an increased risk of CHD when community controls were used (adjusted OR 0.87, 95% CI 0.63-1.19), or when hospital controls were used (adjusted OR 1.00, 95% CI 0.63-1.60), or when both control groups were combined (adjusted OR 1.00, 95% CI 0.74-1.34). Risk of CHD did not increase with use of individual types except gul, frequency, duration, past use of SLT products, or using the RAQ to re-classify cases and controls. There was a significant association between gul use and CHD when both controls were combined (adjusted OR 2.93, 95% CI 1.28-6.70).

CONCLUSIONS

There was no statistically significant association between SLT use in general and CHD among non-smoking adults in Bangladesh. Further research on the association between gul use and CHD in Bangladesh along with SLT use and CHD in other parts of the subcontinent will guide public health policy and interventions that focus on SLT-related diseases.

Who is using snus? - Time trends, socioeconomic and geographic characteristics of snus users in the ageing Swedish population

BACKGROUND

The prevalence of smoking in Sweden has decreased in recent decades, and is now among the lowest in the world. During the same period, the use of Swedish moist oral snuff, a smokeless tobacco called snus, has increased. Few studies have evaluated time trends of the socioeconomic and geographic characteristics of snus users in Sweden. This paper contributes to filling that gap.

METHODS

This study utilized the Linnaeus Database, which links national registers with comprehensive individual data on socioeconomic status (SES) to health data from a large ongoing health survey, the Västerbotten Intervention Programme (VIP). The VIP targets the entire middle-aged population of Västerbotten county at ages 40, 50 and 60 years with yearly cross-sectional surveys including self-reported data on tobacco habits. Time trends of snus use among 92,563 VIP-participants across different areas of residence and smoking groups were investigated graphically. Logistic regression was performed to estimate the associations between SES and geographical variables and current use versus non-use of snus.

RESULTS

Overall, in parallel to decreasing smoking, the increasing trend of snus use in this middle-aged population continues, particularly in 40-year-olds. In both genders, the highest prevalence of snus use was observed among previous smokers. The prevalence of snus use also increased over time among smokers, and was consistently higher compared to those who had never smoked. Among males - both those who had never smoked and previous smokers - low education (OR 1.21, 95%CI 1.06-1.40 and OR 1.28, 95%CI 1.14-1.43), living alone (OR 1.16, 95%CI 1.07-1.27 and OR 1.13, 95%ci 1.04-1.23), low income and living in rural areas was associated with using snus, while this was not seen among male current smokers. Among women, living alone was associated with using snus irrespective of smoking habits. Among female smokers, the OR for snus use increased with higher education.

CONCLUSIONS

A disadvantaged social profile and also higher prevalence in rural areas is observed among male snus users who had never smoked or were previous smokers. Among male smokers there was no association between SES and use of snus. The prevalence of snus use among women is increasing, but is still considerably lower than that of men. The association between snus and SES characteristics is less pronounced among women, although snus is clearly linked to living alone. These patterns should be taken into consideration in tobacco control policies.

[Smokeless tobacco]

Use of smokeless tobacco (ST) (chewing tobacco and snuff) can lead to a number of consequences detrimental to health. ST rapidly delivers high doses of nicotine, which can lead to dependence and is also a source of carcinogenic nitrosamines. Changes usually develop in the mouth area where the ST is most often placed. Non-malignant oral lesions include leuko-oedema, hyperkeratotic lesions of the oral mucosa and localised periodontal disease. Oral premalignant lesions are leukoplakia, erythroplakia, submucosal fibrosis and lichen planus. Betel chewing, with or without tobacco, may increase the incidence of oral cancer. There is conflicting evidence with regard to snuff users about the risk of oral and gastro-oesophageal cancer. ST use is a risk factor for pancreatic cancer and may increase the risk of fatal myocardial infarction and ischemic stroke. During pregnancy, ST is associated with an increase in pre-eclampsia, preterm delivery and stillbirth. Nicotine replacement therapy and bupropion reduce withdrawal symptoms and tobacco craving during ST cessation. However, they have not been shown to help long-term abstinence. Information concerning the potential hazards of ST products should be incorporated into educational programmes to discourage its use and to help users to quit. Smokeless tobacco is not recommended to help smoking cessation.

Smokeless tobacco (snus) and risk of heart failure: results from two Swedish cohorts

BACKGROUND

Oral moist snuff (snus) is discussed as a safer alternative to smoking, and its use is increasing. Based on its documented effect on blood pressure, we hypothesized that use of snus increases the risk of heart failure.

DESIGN

Two independent Swedish prospective cohorts; the Uppsala Longitudinal Study of Adult Men (ULSAM), a community-based sample of 1076 elderly men, and the Construction Workers Cohort (CWC), a sample of 118,425 never-smoking male construction workers.

METHODS

Cox proportional hazards models were used to investigate possible associations of snus use with risk of a first hospitalization for heart failure.

RESULTS

In ULSAM, 95 men were hospitalized for heart failure, during a median follow up of 8.9 years. In a model adjusted for established risk factors including past and present smoking exposure, current snus use was associated with a higher risk of heart failure [hazard ratio (HR) 2.08, 95% confidence interval (CI) 1.03-4.22] relative to non-use. Snus use was particularly associated with risk of non-ischaemic heart failure (HR 2.55, 95% CI 1.12-5.82). In CWC, 545 men were hospitalized for heart failure, during a median follow up of 18 years. In multivariable-adjusted models, current snus use was moderately associated with a higher risk of heart failure (HR 1.28, 95% CI 1.00-1.64) and non-ischaemic heart failure (HR 1.28, 95% CI 0.97-1.68) relative to never tobacco use.

CONCLUSION

Data from two independent cohorts suggest that use of snus may be associated with a higher risk of heart failure.

Changing patterns of tobacco use in a middle-aged population: the role of snus, gender, age, and education

BACKGROUND

In Sweden, the smoking prevalence has declined. In 2007, it was among the lowest in the industrialized world. A steady increase in the use of Swedish oral moist snuff, snus, has occurred in parallel. This development is neither solicited by authorities nor the medical establishment, but rather has occurred along with increased awareness of the dangers of smoking, and has been promoted by product development and marketing of snus.

OBJECTIVE

To evaluate time trends in patterns of tobacco use in northern Sweden during 1990-2007.

DESIGN

Cross-sectional (99,381 subjects) and longitudinal (26,867 subjects) data from the Västerbotten Intervention Programme (VIP) 1990-2007 were analyzed. All adults in Västerbotten County are invited to a VIP health examination at ages 40, 50, and 60 years, and until 1995 also 30 years. Smoking and use of snus were evaluated by gender, age and educational groups. Intermittent smoking was categorized as smoking.

RESULTS

From the period 1990-1995 to the period 2002-2007, smoking prevalence decreased from 26 to 16% among men and from 27 to 18% among women. The differences in prevalence increased between educational groups. The decline in smoking was less and the increase of snus use was greater among those with basic education. The use of snus among basic-educated 40-year-olds reached 35% among men and 14% among women during 2002-2007. Dual smoking and snus use increased among men and women with basic education. Smoking without snus use was more prevalent among women. Gender differences in total smoking prevalence (smoking only plus dual use) were small in all age groups, but increased among those with basic education reaching 7.3% during 2002-2007, with women being more frequent smokers. Smoking prevalences were similar among never, former and current snus users. Among the 30,000 former smokers, 38% of men and 64% of women had never used snus. Longitudinal data showed a decline in total tobacco use from baseline until follow-up and this was mainly due to a smoking cessation rate of<1% a year. Snus use was started by 6.2% of the 30-year-old women (age at baseline), and this contributed to a stable prevalence of total tobacco use in this group. Seventy percent of baseline snus users still used snus at follow-up. Among smokers, 55% continued smoking, 12% of men and 7% of women switched to snus. Among those with dual tobacco use at baseline, a third of men and a fourth of women remained dual users 10 years later.

CONCLUSION

There are increasing differences in tobacco use between educational groups. Higher smoking and snus use prevalence are found among those with basic education, and this is most pronounced in the younger group of this middle-aged population. In spite of a higher prevalence of smoking without snus use among women, total smoking prevalence is similar in men and women due to a higher prevalence of dual tobacco use, i.e. snus and cigarettes, among men. The increase in snus use is being paralleled by a slight increase in dual use and the smoking prevalence does not seem to be influenced by snus. This should be the subject of further studies and also have implications for tobacco control policies.

Weight gain and incident obesity among male snus users

Background

Snus is a moist smokeless tobacco product which has recently reached beyond its original market of Scandinavia. Snus is now being increasingly used in both the United States and South Africa. The effect of snus use on weight is unknown. This study has therefore investigated the relationship between the use of snus, weight gain (≥5%) and the incidence of obesity (body mass index ≥30 kg/m²).

Methods

The study participants (n = 9,954 males living in Stockholm County, Sweden) were recruited in 2002 and reassessed in 2007. Tobacco use was categorized according to information obtained in both the baseline and follow-up surveys. Outcomes were assessed by comparing self-reported weight and body mass index between the baseline and follow-up surveys.

Results

Stable current snus use (according to both surveys), compared to never having used any kind of tobacco, seemed to be associated with both weight gain (odds ratio = 1.31, 95% confidence interval: 1.04-1.65) and incident obesity (odds ratio = 1.93, 95% confidence interval: 1.13-3.30) after adjustment for age, baseline weight, alcohol consumption, physical activity, education, consumption of fruit and berries, and the frequency of having breakfast. No associations with incident obesity or weight gain were seen for stable former users of snus (according to both surveys) or among men who quit or began using snus during follow-up.

Conclusions

These data suggest that the use of snus is moderately associated with weight gain and incident obesity among men.

Summary of the epidemiological evidence relating snus to health

Interest in snus (Swedish-type moist snuff) as a smoking alternative has increased. This wide-ranging review summarizes evidence relating snus to health and to initiation and cessation of smoking. Meta-analyses are included. After smoking adjustment, snus is unassociated with cancer of the oropharynx (meta-analysis RR 0.97, 95% CI 0.68-1.37), oesophagus (1.10, 0.92-1.33), stomach (0.98, 0.82-1.17), pancreas (1.20, 0.66-2.20), lung (0.71, 0.66-0.76) or other sites, or with heart disease (1.01, 0.91-1.12) or stroke (1.05, 0.95-1.15). No clear associations are evident in never smokers, any possible risk from snus being much less than from smoking. "Snuff-dipper's lesion" does not predict oral cancer. Snus users have increased weight, but diabetes and chronic hypertension seem unaffected. Notwithstanding unconfirmed reports of associations with reduced birthweight, and some other conditions, the evidence provides scant support for any major adverse health effect of snus. Although some claims that snus reduces initiation or encourages quitting are unsoundly based, snus seems not to increase initiation, as indicated by few smokers using snus before starting and current snus use being unassociated with smoking in adults (the association in children probably being due to uncontrolled confounding), and there are no reports that snus discourages quitting.

Socio-demographic, lifestyle and health characteristics among snus users and dual tobacco users in Stockholm County, Sweden

BACKGROUND

Socio-demographic and lifestyle characteristics of snus users have not been systematically described. Such knowledge is pivotal for tobacco control efforts and for the assessment of health effects of snus use.

METHODS

A cross-sectional study was conducted, based on the Stockholm Public Health Survey, including a population-based sample of 34,707 men and women aged 18-84 years. We examined how socio-demographic, lifestyle and health-related characteristics were associated with the prevalence of current daily snus use, smoking and dual tobacco use. Logistic regression was used to calculate odds ratios of prevalence (ORs) and 95% confidence intervals (CIs).

RESULTS

Low educational level (OR = 1.60, CI = 1.41-1.81 and OR = 1.49, CI = 1.17-1.89, for men and women respectively), as well as occupational class and low income were associated with snus use. Some unfavourable lifestyle characteristics, including risky alcohol consumption (males: OR = 1.81, CI = 1.63-2.02; females: OR = 1.79, CI = 1.45-2.20), binge drinking and low consumption of fruit and vegetables were also associated with snus use. In contrast, physical inactivity and overweight/obesity were not, nor was perceived health. The prevalence of smoking followed steeper gradients for social as well as lifestyle characteristics. Overweight and obese men were however less often smokers. Perceived poor general health and psychological distress were highly related to smoking. Social disadvantage, as well as unhealthy lifestyle and self-reported poor health were strongly associated with dual use. There were limited differences between men and women.

CONCLUSIONS

The social, lifestyle and health profiles of exclusive snus users in Stockholm County are less favourable than those of non-users of tobacco, but more advantageous than those of exclusive smokers. This knowledge should guide tobacco control measures as well as the interpretation of health risks linked to snus use.

Does dual use jeopardize the potential role of smokeless tobacco in harm reduction?

INTRODUCTION

The use of smokeless tobacco as part of a strategy to reduce the harm from cigarette smoking is a topic of debate within the tobacco control and public health communities. One concern voiced regarding endorsement of such a tactic is the possibility of actually increasing harm should current smokers adopt dual cigarette/smokeless tobacco use (dual use), which could lead to unintended consequences by perpetuating cigarette smoking, diminishing tobacco cessation, or increasing tobacco-related harm.

METHODS

Here, we review the available literature on health effects and trajectories of use among dual users from a variety of U.S. and European epidemiological studies.

RESULTS

These data suggest that there are not any unique health risks associated with dual use of smokeless tobacco products and cigarettes, which are not anticipated or observed from cigarette smoking alone. Furthermore, studies show that dual users smoke fewer cigarettes than exclusive smokers, and studies of tobacco use patterns over time (tobacco use trajectory data) indicate that dual users are more likely than exclusive cigarette smokers to cease smoking.

CONCLUSIONS

Overall, the concern about dual use appears to be contradicted by the evidence in the literature that dual use of smokeless tobacco and cigarettes may result in reduction in smoking-related harm as smoking intensity is decreased and smoking cessation increases.

The acute effects of smokeless tobacco on central aortic blood pressure and wave reflection characteristics

The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood pressure and wave reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline measurements were recorded. Pulse wave analysis using radial artery applanation tonometry was performed in triplicate at baseline (0 min) and at 10-min intervals during (10, 20 and 30 min) and after (40, 50 and 60 min) ST use. An acute dose of ST was associated with a significant increase in heart rate (HR), central aortic systolic and diastolic blood pressure, peripheral brachial systolic and diastolic blood pressure, and aortic augmentation index normalized to a fixed heart rate of 75 bpm (AIx@75). Furthermore, ejection duration and round trip travel time of the reflected pressure wave (Δt(p)) were significantly decreased as a result of one time ST use. As a result of changes in aortic pressure wave reflection characteristics, there was a significant increase in wasted left ventricular pressure energy (LVE(w)) and the tension-time index (TTI) as a result of ST use. In conclusion, one time use of ST elicits significant transient increases in HR, central aortic pressures, AIx@75, the TTI and LVE(w). Chronic users subjected to decades of elevated central pressures and left ventricular work may have an increased cardiovascular risk as central aortic pressures are even more strongly related to cardiovascular outcomes than peripheral blood pressures.

Evaluation of biomarkers of exposure in adult cigarette smokers using Marlboro snus

INTRODUCTION

It has been reported that adult smokers (AS) may be considering smokeless tobacco products as an alternative to smoking. The objective of this study was to evaluate the change in exposure in AS using Marlboro snus (MSNUS) (a tobacco pouch product in test market in June 2007).

METHODS

AS were randomized into the following groups--CS: subjects (n = 30) continue smoking their own brand; DU: subjects (n = 60) reduced their daily cigarette consumption by >or=50% and were allowed to use MSNUS; SN: subjects (n = 15) stopped smoking their cigarettes but were allowed to use MSNUS; NT: subjects (n = 15) were not allowed to use any tobacco products for the entire duration of the 8-day study. Biomarkers of smoke exposure (BOE) measured at baseline and postbaseline were 24-hr urinary excretion of metabolites of N-nitrosamines, nicotine (urine and plasma), aromatic amines, benzene, and polycyclic aromatic hydrocarbon; urine mutagenicity; and carboxyhemoglobin at various timepoints.

RESULTS

Statistically significant (p < .05) reductions in all the urinary BOE were observed in the DU group compared with the CS group. After correcting for the residual effect, a proportionate reduction (approximately 50%) in most of the biomarkers was observed. Even larger reductions, similar to the NT group, were observed in the SN group.

DISCUSSION

The proportionate reduction in exposure when reducing the number of cigarettes by 50% and using MSNUS, under the consumption patterns observed, suggest that the AS did not appear to alter their smoking behavior. The added exposure from MSNUS usage in this group was minimal. The AS sustained substantial reductions in exposure when using MSNUS exclusively.

Association of exclusive smokeless tobacco consumption with hypertension in an adult male rural population of India

Introduction

Tobacco consumption is a major source of mortality and morbidity in India . Prevalence of smokeless tobacco (ST) consumption in India is around 20%. Studies have shown increased prevalence of cardiovascular disease risk factors and an increased incidence of adverse cardiovascular events among the ST consumers. This is a cross-sectional study done to look into the association of exclusive smokeless tobacco consumption with hypertension, in an adult male rural population of north India.

Methods

All male residents of a village in north India above 15 years of age, who did not have any acute or chronic morbidity were included after taking an informed consent. Subjects were interviewed regarding their demographic profile, socioeconomic status and tobacco consuming habits. Current smokeless tobacco user was defined as one who has ever consumed tobacco orally in past 1 month. Blood pressure of the subjects was also recorded. Cut offs used for systolic and diastolic hypertension were 140 mm hg and 90 mm Hg respectively.

Results

443 subjects were included in the study. Prevalence of exclusive ST users was 21% while 19.4% consumed both forms and 26.6% did not take any form of tobacco. Mean systolic and diastolic BP were significantly higher in exclusive ST users(systolic BP=139.2+17.4,diastolic BP = 86.8+11.5)as compared to the non users(systolic BP= 135.7+18.8 , diastolic BP= 82.6 +11.5; p value < 0.05). The prevalence of diastolic hypertension was significantly higher in exclusive ST users as compared to non users ( 40.9%, 22.9% ;p value = 0.01) . The OR for diastolic hypertension in male ST users was 2.3( 95% C.I. = 1.3-4.3). Prevalence of systolic hypertension was higher in exclusive ST users too though this was not statistically significant (43%,36.4%;p value = 0.39.).

Conclusion

ST consumption is associated with increased prevalence of high BP in the adult male rural population.This is an indicator of increased predisposition to major adverse cardiac events later in their life time. Prevention of ST consumption could be an important intervention in preventing the ongoing upswing in prevalence of chronic heart disease.

The association of snus and smoking behaviour: a cohort analysis of Swedish males in the 1990s

BACKGROUND

The European Union has banned sales of moist snuff (snus) in all member states, with the exception of Sweden. The ban is motivated by the potential adverse health effects of snus, but snus may also help people to avoid smoking or stop tobacco use.

AIMS

The purpose of this study is to investigate the association between snus and smoking behaviour.

MEASUREMENTS

The Swedish Survey of Living Conditions (ULF) health interview panel running from 1988/9 to 1996/7 was used to examine the gross and net flows between smoking and snus among Swedish males. Females were excluded from the analysis due to low snus prevalence. Contingency table models were used to investigate several hypotheses about the relationships between snus and smoking behaviour.

FINDINGS

We found clear associations between the two habits. For the younger cohort (age 16-44 years), snus use contributed to approximately six smoking quitters per smoking starter attributable to snus. For the older cohort (age 45-84) there were slightly more than two quitters per starter. In terms of odds ratios, in the younger group smoking cessation attributable to snus was twice as common as smoking initiation, but in the older group the odds of starting smoking attributable to snus was 2.5 times higher than for quitting.

CONCLUSIONS

Snus contributed to the reduction of smoking among Swedish males in the 1990s. Snus had different effects among non-smokers and smokers in different age groups.