Use of smokeless tobacco and risk of myocardial infarction and stroke: systematic review with meta-analysis

Smokeless Tobacco Risk Comparison and Other Debate Messages in the News

OBJECTIVES

Public health professionals have debated the use of smokeless tobacco (SLT) over cigarettes for harm reduction. This article describes SLT and cigarette risk comparisons and other SLT "debate" messages potentially reaching the public through news stories.

METHODS

We conducted a content analysis of SLT-related 2006-10 articles from top newspapers and selected news wires.

RESULTS

About 16% of articles (N = 677) referred to SLT as less harmful than smoking, attributing these messages to public health professionals as frequently as to tobacco company representatives. About 29% of articles included an "anti" SLT message, including variously phrased warnings that SLT is not a safe smoking alternative, or other potential consequences such as youth uptake.

CONCLUSION

Professionals should begin developing and using more consistent messages about SLT's risks.

A qualitative study of smokers' responses to messages discouraging dual tobacco product use

Cigarette companies increasingly promote novel smokeless tobacco products to smokers, encouraging them to use smokeless tobacco in smoke-free environments. New messages may counteract this promotion. We developed 12 initial anti-smokeless message ideas and tested them in eight online focus groups with 75 US smokers. Those smokers who never tried smokeless tobacco were unaware of health risks of novel smokeless tobacco products, perceived scary messages as effective and acknowledged the addictive nature of nicotine. Smokers who had tried smokeless tobacco shared their personal (mainly negative) experiences with smokeless tobacco, were aware of health risks of novel smokeless tobacco products, but denied personal addiction, and misinterpreted or disregarded more threatening messages. Portraying women as smokeless tobacco users was perceived as unbelievable, and emphasizing the lack of appeal of novel smokeless tobacco products was perceived as encouraging continued smoking. Future ads should educate smokers about risks of novel smokeless tobacco products, but past users and never users may require different message strategies.

Tobacco use habits among Swedish female youth athletes and the influence of the social environment

AIM

This study examined the prevalence of tobacco habits and the influence of the social environment among Swedish female athletes representing both individual and team sports in Sweden.

MATERIAL AND METHOD

A self-reported cross-sectional survey was performed with 791 female athletes 15-24 years old representing ten of the most common sports in Sweden. The questions related to the participants' involvement in sports and their tobacco habits.

RESULTS

Findings revealed that a large proportion of the female athletes had never smoked (65%) or used snus (74%). However, a considerable portion of the participants had tried smoking (27%) or using snus (20%), especially those involved in team sports. Results also showed statistically significant associations between female athletes' smoking habits and those of both their mothers and their peers, but not with the tobacco habits of their coaches, indicating that coaches do not influence the female athletes' use of tobacco.

CONCLUSION

In conclusion, this study indicated that the vast majority of female athletes did not use tobacco. A significant portion had sometimes tried tobacco, especially members of team sports, but this behaviour did not seem to be influenced by the tobacco habits of their coaches.

Sociodemographic correlates of exclusive and concurrent use of smokeless and smoked tobacco products among Nigerian men

INTRODUCTION

This study sought to determine the sociodemographic correlates of exclusive and concurrent use of smokeless tobacco (SLT) and smoking (i.e., dual use) and to explore the association between SLT use and the amount of cigarettes smoked per day.

METHODS

Data were obtained from a nationally representative sample of Nigerian men aged 15-59 years (N = 15,453) who participated in the 2008 Nigerian Demographic and Health Survey (NDHS). The NDHS used an interviewer-administered questionnaire to collect data on participants' sociodemographic characteristics and tobacco use status. Taking account of the multistage sampling used in the NDHS, data analyses included descriptive statistics, chi-square analysis, and multivariable adjusted multinomial logistic regression analysis.

RESULTS

Of the respondents, 12.2% (n = 1,842) were tobacco users, out of which 24.5% (n = 477) were exclusive SLT users, 69% (n = 1,236) were exclusive smokers, and 6.5% (n = 129) were dual users. Both SLT use and smoking were most prevalent among the Igbo ethnic group and among the least educated men. SLT use was most prevalent among those in the southeast (9.75%) and north-central (7.71%) regions, where smoking was also common. The number of cigarettes smoked per day was not significantly different among dual users when compared with exclusive smokers (7.3 vs. 5.6; p = .088). Dual users were also more likely to self-identify as traditionalists (RRR = 6.03; 95% CI = 2.96-12.28) compared with self-identifying as practicing Islam or Christianity.

CONCLUSIONS

There are distinctive ethnic and regional differences in tobacco use patterns among Nigerian men, and SLT use was not associated with reduced smoking intensity among dual users.

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.

Cost and clinical consequences of smoking cessation in outpatients after cardiovascular disease: a retrospective cohort study

This cohort retrospective study explored the cost and clinical consequences of smoking cessation in outpatients after cardiovascular events (CVEs), in Spain. A total of 2,540 patients (68.1 years; 60.7% male; 8.4% smokers, 52.9% ex-smokers, and 38.7% never smokers) fulfilling the selection criteria and followed up throughout a period of 36 months after the event were considered eligible for analysis. Total costs were higher among current smokers in comparison with ex-smokers and never smokers (€7,981 versus [vs] €7,322 and €5,619, respectively) (P < 0.001). Both health care costs (€6,273 vs €5,673 and €4,823, respectively) (P < 001) and loss of productivity at work costs (€1,708 vs €1,650 and €796, respectively) (P < 001) accounted for such differences. There was also a difference in CVE recurrence rates (18.6% vs 16.5% and 9.6%, respectively) (P < 01). Smoking cessation in CVE outpatients was associated with lower cost and risk of CVE recurrence compared with smokers, and their health status was similar to that of never smokers, in routine clinical practice in Spain.

Smokeless tobacco and cardiovascular disease in low and middle income countries

Smoking is an important cardiovascular risk factor, however, use of smokeless tobacco has not been well studied. Smokeless tobacco use is high in countries of South and Southeast Asia, Africa and Northern Europe. Meta-analyses of prospective studies of smokeless tobacco users in Europe reported a relative risk for fatal coronary heart disease of 1.13 (confidence intervals 1.06-1.21) and fatal stroke of 1.40 (1.28-1.54) while in Asian countries it was 1.26 (1.12-1.40). Case-control studies reported significantly greater risk for acute coronary events in smokeless tobacco users (odds ratio 2.23, 1.41-3.52), which was lower than smokers (2.89, 2.11-3.96), and subjects who both chewed and smoked, had the greatest risk (4.09, 2.98-5.61). There is a greater prevalence of hypertension and metabolic syndrome in users of smokeless tobacco. Smokeless tobacco use leads to accelerated atherothrombosis similar to smoking. There is an urgent need for public health and clinical interventions to reduce smokeless tobacco addiction.

A content analysis of smokeless tobacco coverage in U.S. newspapers and news wires

INTRODUCTION

Research attention on smokeless tobacco (SLT) has focused on SLT use, health risks, harm-reduction potential, and risk perceptions, but few studies have examined mediated communications about SLT. This study aims to contribute to the literature by providing the first description of SLT coverage in the news, an important communication channel given its ability to educate and shape public opinion about tobacco issues.

METHODS

A content analysis was conducted on SLT-related news and opinion articles between 2006 and 2010 from top circulating national and state newspapers and select news wires. Articles were coded for the main SLT topic, SLT risk references, and slant of opinion articles.

RESULTS

SLT was discussed in news/feature articles (n = 677) in terms of business (28%), new products, product regulation and harm reduction (19%), prevention/cessation (11.4%), taxation (10.2%), profiles/trends in use (9%), bans (8.1%), and tobacco industry promotional activities (4.9%). Health risk references (i.e., addictiveness, carcinogenicity, and specific health effects including oral cancer) were found in 40% of articles, though frequency differed by article topic. Although the majority of opinion articles (n = 176) conveyed an anti-SLT slant (64%), 25.6% were pro-SLT.

CONCLUSIONS

SLT topics of both national and local importance are covered in the news. Public health professionals can participate in SLT coverage by sending in press releases about new study findings, events, or resources and by submitting opinion pieces to share views or respond to previous coverage. Research on SLT news should continue given its potential to shape the public's SLT knowledge and opinions.

The effect of Swedish snuff (snus) on offspring birthweight: a sibling analysis

Current observational evidence indicates that maternal smoking during pregnancy is associated with reduced birthweight in offspring. However, less is known about the effect of smokeless tobacco on birthweight and about the possible mechanisms involved in this relationship. This paper studies the effect of Swedish smokeless tobacco (snus) on offspring birthweight comparing the results obtained from a conventional linear regression analysis and from a quasi-experimental sibling design using a multilevel linear regression analysis. From the Swedish Medical Birth Register, we investigated 604,804 singletons born between 2002 and 2010. From them, we isolated 8,861 siblings from 4,104 mothers with discrepant snus-use habits (i.e., women who had at least one pregnancy during which they used snus and at least one other pregnancy in which they did not). The conventional analysis shows that continuous snus use throughout the pregnancy reduces birthweight in 47 g while quitting or relapsing snus has a minor and statistically non-significant effect (−6 g and −4 g, respectively). However, using a sibling analysis the effect observed for mothers who continue to use snus during pregnancy is less intense than that observed with previous conventional analyses (−20 g), and this effect is not statistically significant. Sibling analysis shows that quitting or relapsing snus use after the first trimester slightly reduces birthweight (14 g).However, this small change is not statistically significant. The sibling analysis provides strong causal evidence indicating that exposure to snus during pregnancy has a minor effect on birthweight reduction. Our findings provide a new piece of causal evidence concerning the effect of tobacco on birthweight and support the hypothesis that the harmful effect of smoking on birthweight is not mainly due to nicotine.

Ending tobacco-caused mortality and morbidity: the case for performance standards for tobacco products

The US Family Smoking Prevention and Tobacco Control Act and WHO Framework Convention on Tobacco Control provide us with powerful tools to reduce the death and disease caused by the use of tobacco products. One tool that can contribute substantially toward this goal is the authority to establish performance standards for tobacco products. Conjointly with reducing levels of nicotine in cigarettes, performance and quality control standards need to be established for non-combusted tobacco products. Performance standards and incentives should be provided so that tobacco companies are compelled to manufacture and market products with very low or almost non-existent toxicity (eg, nicotine-only products).

Smoking water-pipe, chewing nass and prevalence of heart disease: a cross-sectional analysis of baseline data from the Golestan Cohort Study, Iran

OBJECTIVE

Water-pipe and smokeless tobacco use have been associated with several adverse health outcomes. However, little information is available on the association between water-pipe use and heart disease (HD). Therefore, we investigated the association of smoking water-pipe and chewing nass (a mixture of tobacco, lime and ash) with prevalent HD.

DESIGN

Cross-sectional study.

SETTING

Baseline data (collected in 2004-2008) from a prospective population-based study in Golestan Province, Iran.

PARTICIPANTS

50 045 residents of Golestan (40-75 years old; 42.4% men).

MAIN OUTCOME MEASURES

ORs and 95% CIs from multivariate logistic regression models for the association of water-pipe and nass use with HD prevalence.

RESULTS

A total of 3051 (6.1%) participants reported a history of HD, and 525 (1.1%) and 3726 (7.5%) reported ever water-pipe or nass use, respectively. Heavy water-pipe smoking was significantly associated with HD prevalence (highest level of cumulative use vs never use, OR=3.75; 95% CI 1.52 to 9.22; p for trend=0.04). This association persisted when using different cut-off points, when restricting HD to those taking nitrate compound medications, and among never cigarette smokers. There was no significant association between nass use and HD prevalence (highest category of use vs never use, OR=0.91; 95% CI 0.69 to 1.20).

CONCLUSIONS

Our study suggests a significant association between HD and heavy water-pipe smoking. Although the existing evidence suggesting similar biological consequences of water-pipe and cigarette smoking make this association plausible, results of our study were based on a modest number of water-pipe users and need to be replicated in further studies.

The chemical composition of smokeless tobacco: a survey of products sold in the United States in 2006 and 2007

Selected toxicant concentrations and other chemical measures have been determined for 43 U.S. smokeless tobacco products sold in 2006 and 2007. Products evaluated included moist snuff, dry snuff, loose leaf, plug, dissolvable and snus tobacco brands. Reference products available for scientific research purposes and eleven Swedish products were also evaluated and compared to the commercial products studied. Chemical endpoints determined included benzo[a]pyrene (B[a]P), N'-nitrosonornicotine (NNN), N'-nitrosoanatabine (NAT), N'-nitrosoanabasine (NAB), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-Nitrosodimethylamine (NDMA), nitrite, cadmium, lead, arsenic, nickel, chromium, chloride, water, pH and nicotine. Different toxicant profiles were observed for the products studied, with snus tobacco brands generally containing relatively low concentrations of B[a]P and tobacco specific nitrosamines (TSNAs) compared to other moist snuffs. Smokeless tobacco reference product toxicant profiles were similar to corresponding commercial products, with the exception of the TSNA content of the dry snuff reference material. TSNA concentrations observed for all commercial products were lower than historically reported values, likely reflecting changes in product shelf life, tobacco curing practices and, possibly, product blend formulations during the last 20-30 years. The survey results summarized provide a temporal point of comparison with future data anticipated from FDA "harmful and potentially harmful constituents in tobacco products" reporting.

Trends in the use of smokeless tobacco in United States, 2000-2010

OBJECTIVES/HYPOTHESIS

To quantify trends in the use of smokeless tobacco in the United States.

STUDY DESIGN

Longitudinal analysis of national population database.

METHODS

The National Health Interview Surveys for 2000, 2005, and 2010 were analyzed for adult responses to specific questions regarding smokeless tobacco use, which includes chewing tobacco and snuff. Smokeless tobacco lifetime exposure, current use, and frequency of use were determined according to each sampled year, examining for trends over the past decade. Subset analysis for young adults (ages 18-44 years) was conducted. Demographic factors associated with smokeless tobacco use were also determined.

RESULTS

A total of 86,270 adults were surveyed. Among all adults, the proportions of those who had ever tried chewing tobacco were 7.1 ± 0.2%, 8.5 ± 0.2%, and 9.2 ± 0.2% for 2000, 2005, and 2010, respectively (P < .001). Similarly, the proportions of those who had ever tried snuff were 4.4 ± 0.2%, 7.5 ± 0.2%, and 8.4 ± 0.3%, respectively (P < .001). In aggregate, the proportions who were regular users of chewing tobacco remained stable over the survey years: 1.3 ± 0.1%, 1.1 ± 0.1%, and 1.2 ± 0.1%, respectively (P = .382). In contrast, the percentages who were regular users of snuff tobacco increased significantly over the survey years: 1.4 ± 0.1%, 1.6 ± 0.1%, and 2.0 ± 0.1% (P < .001). The proportion of young adults regularly using snuff rose to 2.8 ± 0.2% (P < .001) in 2010. Male sex, non-Hispanic ethnicity, white race, and less than a high school education were characteristics that were strongly associated with smokeless tobacco use.

CONCLUSIONS

There was a trend toward increased smokeless tobacco use, mainly snuff, in the United States in the past decade. This trend was more prominent among young adults and likely will have future health-care implications.

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.

Effects of a Fact Sheet on beliefs about the harmfulness of alternative nicotine delivery systems compared with cigarettes

BACKGROUND

This study explored the value of providing information in a Fact Sheet to correct misperceptions about the relative harmfulness of nicotine replacement products (NRT) and smokeless tobacco (ST), when compared to cigarette smoking.

METHODS

Four convenience samples from different countries (Australia, UK, Sweden and USA) were surveyed concerning their beliefs about the relative harmfulness of smokeless tobacco and NRT. Study participants were given the Fact Sheet that explained that nicotine, as used by consumers, is not particularly harmful and explained why. They were resurveyed one week later regarding their beliefs about the relative harmfulness of smokeless tobacco and NRT and future intentions to use the products.

RESULTS

In all four samples knowledge increased by similar amounts and beliefs regarding the lower harmfulness of smokeless tobacco increased. However, misconceptions remained common and responses to belief measures were not always consistent. Likelihood of use of ST increased in all four samples after exposure to the Fact Sheet, but interest in NRT use only increased in the US sample.

CONCLUSIONS

A Fact Sheet such as this one can help address misconceptions about NRT and smokeless tobacco, at least in the short term. However, as is true of most educational interventions, exposure to a single educational session is not sufficient to overcome misperceptions that smokers have about the relative harmfulness of oral versus combustible forms of nicotine delivery.

Why Do Bangladeshi People Use Smokeless Tobacco Products?

Despite scientific evidence about the harmful effects of smokeless tobacco (SLT), it is widely used in Bangladesh. This study explored perceptions about health effects of SLT use. Semistructured interviews were conducted with 1812 nonsmoking adults. About 40% of the participants were current SLT users or had used SLT in the past. Family members’ influence was the main factor for initiation. The participants believed that people continued using SLT because of addiction (52%) and as a part of their lifestyle (23%). The majority of participants (77%) did not mention any benefit, but SLT users considered it to be a remedy for toothache ( P < .05). Almost all participants mentioned that SLT was harmful and causes heart disease, cancer, and tuberculosis. Doctors’ advice was the common motivating factor to quit. Health promotion interventions should highlight the adverse effects of SLT use, which outweigh the perceived benefits, and should consider addressing the role of family in SLT initiation and use.

Non-cigarette tobacco products: what have we learnt and where are we headed?

A wide variety of non-cigarette forms of tobacco and nicotine exist, and their use varies regionally and globally. Smoked forms of tobacco such as cigars, bidis, kreteks and waterpipes have high popularity and are often perceived erroneously as less hazardous than cigarettes, when in fact their health burden is similar. Smokeless tobacco products vary widely around the world in form and the health hazards they present, with some clearly toxic forms (eg, in South Asia) and some forms with far fewer hazards (eg, in Sweden). Nicotine delivery systems not directly reliant on tobacco are also emerging (eg, electronic nicotine delivery systems). The presence of such products presents challenges and opportunities for public health. Future regulatory actions such as expansion of smoke-free environments, product health warnings and taxation may serve to increase or decrease the use of non-cigarette forms of tobacco. These regulations may also bring about changes in non-cigarette tobacco products themselves that could impact public health by affecting attractiveness and/or toxicity.

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.

Effects of smokeless tobacco "Maras powder" use on nitric oxide and cardiovascular risk parameters

BACKGROUND

Smokeless tobacco use is common in various parts of the world. In Turkey a type of smokeless tobacco called "Maras powder" is widely used in southeastern region. Smoking is known to have an adverse effect on nitric oxide and cardiovascular risk factors. The aim of this study was to evaluate whether there is difference between the effects of Maras powder and cigarette smoking on the cardiovascular risk factors and nitric oxide levels.

METHODS

In the study, participants were 48 Maras powder users, 50 cigarette smokers and 45 nontobacco user subjects. Blood samples were collected and hematological parameters and lipid parameters were measured. Plasma Nitric oxide level was also detected by using the Griess method.

RESULTS

Plasma total cholesterol, LDL-cholesterol, triglyceride levels were significantly higher in Maras powder and cigarette smokers group than in the nontobacco user group (p<0.001). Plasma HDL-cholesterol levels were significantly lower in Maras powder and cigarette smokers group than in the nontobacco user group (p<0.001). Plasma Nitric oxide levels were found significantly lower in Maras powder and cigarette smokers group compared to the nontobacco user group (4.9±0.9 µmol/l, 4.8±1 µmol/l, 9.4±3.4 µmol/l, respectively, p<0.001) whereas there was no significant difference between the Maras powder and cigarette smokers group. In multivariate logistic regression model, cigarette smoking (Odds ratio=17.832, p<0.001), Maras powder usage (Odds ratio=12.311, p=0.002) and mean platelet volume (Odds ratio=1.425, p=0.030) remained independently associated with lower Nitric oxide levels.

CONCLUSION

We conclude that Maras powder has similar adverse effects on nitric oxide level and cardiovascular risk parameters and thereby it appears to be harmful as cigarette smoking.

Manufactured and hand-rolled cigarettes and smokeless tobacco consumption in Mozambique: regional differences at early stages of the tobacco epidemic

BACKGROUND

To describe the use of different types of tobacco (manufactured and hand-rolled cigarettes, and smokeless tobacco) in the adult Mozambican population, across regions.

METHODS

A representative sample of 12,902 Mozambicans aged 25-64 years was evaluated in a national household survey conducted in 2003 using a structured questionnaire. The patterns of tobacco consumption were described to highlight the sex-specific differences by age and between urban and rural settings, and between the north, where most of the country's tobacco production is concentrated, and the south of the country, where the wealthiest provinces, closer to the city capital, are located.

RESULTS

The prevalence of current tobacco consumption was 39.9% in men and 18.0% in women. Women consumed predominantly smokeless tobacco (prevalence: 10.1%), especially in the north. Hand-rolled and manufactured cigarettes were the most frequently consumed among men (prevalences: 18.7% and 17.2%, respectively). Additionally, hand-rolled cigarette consumption predominantly occurred in the northern provinces and rural settings, whereas manufactured cigarette consumption predominated in the south and urban areas.

CONCLUSIONS

The overall tobacco consumption was higher than expected for an African country with scarce economic resources, mostly due to traditional forms of consumption. The gender and regional specific patterns of consumption identified in Mozambique may contribute to the development of culturally adapted and locally grounded actions for tobacco control, and stress the need of locale-specific surveillance data and public health action in this field.

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]

The use of snus (smokeless tobacco) can be detrimental to health. Containing carcinogenic nitrosamines (Swedish snus do not contain nitrosamine). Snus delivers rapidly high doses of nicotine which can lead to dependence. It do not induce bronchial carcinoma differently smoked tobacco. Lesions usually develop in the area of the mouth where the snus is placed. Non-malignant oral lesions include leukoedema, hyperkeratotic lesions of the oral mucosa and localised periodontal disease. The most frequently occurring premalignant lesion is leukoplakia. Studies reveal conflicting evidence about the risk of oral and gastroesophageal cancer with regard to snus users. However, the use of snus has proved to be a risk factor in developing pancreatic cancer and increases the risk of fatal myocardial infarction and ischemic stroke. During pregnancy, snus is associated with an increased risk of pre-eclampsia and premature delivery. Nicotine substitution therapy and bupropion and varenicline reduce withdrawal symptoms and tobacco craving during snus cessation. However, they have not been shown to assist in long-term abstinence. Information concerning potential hazards of using snus products must be incorporated into health educational programmes in order to discourage its use. Snus is not a recommended product to help in stopping to smoke.

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.

The scientific foundation for tobacco harm reduction, 2006-2011

Over the past five years there has been exponential expansion of interest in tobacco harm reduction (THR), with a concomitant increase in the number of published studies. The purpose of this manuscript is to review and analyze influential contributions to the scientific and medical literature relating to THR, and to discuss issues that continue to stimulate debate. Numerous epidemiologic studies and subsequent meta-analyses confirm that smokeless tobacco (ST) use is associated with minimal risks for cancer and for myocardial infarction; a small increased risk for stroke cannot be excluded. Studies from Sweden document that ST use is not associated with benign gastrointestinal disorders and chronic inflammatory diseases. Although any form of nicotine should be avoided during pregnancy, the highest risks for the developing baby are associated with smoking. It is documented that ST use has been a key factor in the declining rates of smoking and of smoking-related diseases in Sweden and Norway. For other countries, the potential population health benefits of ST are far greater than the potential risks. In follow-up studies, dual users of cigarettes and ST are less likely than exclusive smokers to achieve complete tobacco abstinence, but they are also less likely to be smoking. The health risks from dual use are probably lower than those from exclusive smoking. E-cigarette users are not exposed to the many toxicants, carcinogens and abundant free radicals formed when tobacco is burned. Although laboratory studies have detected trace concentrations of some contaminants, it is a small problem amenable to improvements in quality control and manufacturing that are likely with FDA regulation as tobacco products. There is limited evidence from clinical trials that e-cigarettes deliver only small doses of nicotine compared with conventional cigarettes. However, e-cigarette use emulates successfully the cigarette handling rituals and cues of cigarette smoking, which produces suppression of craving and withdrawal that is not entirely attributable to nicotine delivery. THR has been described as having "the potential to lead to one of the greatest public health breakthroughs in human history by fundamentally changing the forecast of a billion cigarette-caused deaths this century."

Treatment of risk factors to prevent stroke

Much of the decline in stroke incidence and mortality for the past several decades in Western countries has been attributed to better treatment of risk factors. Many epidemiological studies and clinical trials confirmed the importance of managing hypertension. Comparative trials of anti-hypertensive drugs or drug classes have not yielded clear results, but blood pressure variability may play an important role beyond the absolute value of blood pressure. Diabetes therapy remains a conundrum. Although diabetes is clearly a risk factor for ischemic stroke, treatment trials targeting different glycemic goals have not indicated that glucose lowering results in stroke prevention. Trials focused on insulin resistance are ongoing and they may be able to help establish the management of diabetes/impaired glucose tolerance. Evidence for treatment of dyslipidemia has contrasted science to diabetes mellitus. Dyslipidemia has not been strongly or consistently linked to ischemic stroke but the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial showed the impact of statin treatment in stroke prevention. The results of clinical trials investigating dabigatran and rivaroxaban clearly indicate alternative strategies to vitamin K antagonists in stroke prevention for persons with atrial fibrillation. Evidence for stroke prevention by life style modification, treating metabolic syndrome, sleep disordered breathing, lipoprotein (a), hyperhomocysteinemia, and coagulation disorders are also discussed.

Genetics of the association between intelligence and nicotine dependence: a study of male Swedish twins

AIMS

Previous studies have found inverse associations between intelligence quotient (IQ) and cigarette smoking, but the causal pathways linking IQ with smoking status and nicotine dependence (ND) are not well understood. The aim of this study was to explore the associations between IQ and ND using a genetically informative twin design to detect whether any association is because of shared genetic or environmental factors.

DESIGN

A population-based twin cohort with IQ measured in adolescence and ND later in life, analysed by classical twin modeling based on linear structural equations.

SETTING

Swedish national registry data.

PARTICIPANTS

A total of 5040 male twins born 1951-84.

MEASUREMENTS

IQ was measured at military conscription at a mean age of 18 years. ND was self-reported at the ages of 22-57 years using the Fagerström Test for ND scale (FTND). Both cigarette smoking and Swedish snus use were analysed.

FINDINGS

Both IQ and ND showed moderate heritability (0.58 and 0.39, respectively). The heritability of ND was similar for cigarette smoking and snus use. The phenotypic correlation between IQ and ND was weak: -0.11 (-0.16, -0.06) for total ND. Bivariate analysis revealed that this correlation was mainly because of genetic factors, but still the genetic correlation between IQ and ND from cigarette smoking was only -0.24.

CONCLUSIONS

Nicotine dependence, as measured by the Fagerström Test for Nicotine Dependence, shows moderate heritability in both smokers and snus users but is only weakly associated with intelligence quotient; common genetic factors underlying nicotine dependence and intelligence quotient probably account for little of the observed association between smoking and intelligence quotient.

Chewing substances with or without tobacco and risk of cardiovascular disease in Asia: a meta-analysis

OBJECTIVE

To assess whether people who ever use any form of chewing substance in Asia are at increased risk of cardiovascular disease (CVD).

METHODS

PubMed and ISI Web of Science were searched for relevant studies, with no limitation on language or study year. Studies were included if they provided quantitative estimate of the association between ever use of chewing substance and the occurrence of CVD. Two authors independently implemented inclusion criteria, abstracted study characteristics, and performed meta-analysis. Summary relative risks were estimated on the basis of a random effect model. We used Q statistic and Egger's test to examine heterogeneity across studies and potential publication bias, respectively.

RESULTS

Eight eligible studies were included. The relative risk of CVD for ever using chewing substances with or without tobacco was 1.26 (95% confidence interval (CI) 1.12-1.40), which was unchanged when restricted to cohort studies [1.25 (1.08-1.42)] or cohort studies in Taiwan [1.31 (1.12-1.51)]. The summary relative risk for ischemic heart disease was 1.27 (1.02-1.52), and was lowered to 1.26 (0.85-1.67) after exclusion of a cross-sectional study. The overall relative risk for cerebrovascular disease was 1.32 (1.08-1.56). On the basis of the Taiwan data, the summary relative risk of CVD for betel (Areca catechu) chewing was 1.30 (1.17-1.44). Data on dose-response were limited to betel chewing in Taiwan, suggesting a relationship between risk of CVD and cumulative exposure. Two large cohorts in Taiwan reported a greater risk of CVD with betel chewing than with smoking.

CONCLUSIONS

An association was detected between betel chewing with or without tobacco and the risk of CVD. Betel chewing may impose a greater CVD risk than smoking. More effort is needed in developing betel chewing cessation programmes. The relationship between betel chewing and subgroups of CVD requires further investigation.

The association between active smoking, smokeless tobacco, second-hand smoke exposure and insufficient sleep

BACKGROUND

Studies have shown that cigarette smoking is associated with sleep disorders in the general population. But studies examining the association between smokeless tobacco use, second-hand smoke exposure and insufficient rest/sleep are limited.

METHODS

We examined the association between smoking, smokeless tobacco use (n=83,072), second-hand smoke exposure (n=28,557) and insufficient rest/sleep among adults aged ≥20 years in the state-based 2008 Behavioral Risk Factor Surveillance System. Exposure to second-hand smoke was defined as >1 day of exposure to cigarette smoking either at home or in the workplace in the preceding 7 days. Insufficient rest/sleep was defined as not getting enough rest/sleep everyday in the preceding 30 days.

RESULTS

Compared to never smokeless tobacco users, the odds ratio (OR; 95% confidence interval [CI]) of insufficient rest/sleep was 1.16 (1.00-1.36) and 1.74 (1.37-2.22) among former and current users. Compared to non-smokers/non-smokeless tobacco users, the OR (95% CI) of insufficient rest/sleep for those who were both current smokers and current smokeless tobacco users was 2.21 (1.66-2.94). Regarding second-hand smoke exposure among non-smokers, those with second-hand smoke exposure had higher odds for insufficient rest/sleep than those without. In contrast, the odds of insufficient rest/sleep were similar among current smokers with or without second-hand smoke exposure.

CONCLUSIONS

In a multiethnic sample of US adults, compared to non-smokers/non-smokeless tobacco users, those who were both current smokers and current smokeless tobacco users had twice the odds of insufficient sleep. Second-hand smoke exposure was associated with insufficient rest/sleep among non-smokers.

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.

Risk of incident cardiovascular disease among users of smokeless tobacco in the Atherosclerosis Risk in Communities (ARIC) study

Use of smokeless tobacco in the United States has been relatively constant in recent years, as tobacco companies continue aggressive marketing campaigns. The health effects of smokeless tobacco use need further documentation. Thus, the authors examined whether current use of smokeless tobacco was associated with increased incidence of cardiovascular disease (CVD) in 14,498 men and women aged 45-64 years at baseline (1987-1989) in the Atherosclerosis Risk in Communities (ARIC) Study. There were 2,572 incident CVD events (myocardial infarction, coronary revascularization, coronary death, or stroke) during a median of 16.7 years of follow-up (maximum = 19.1 years). Current use of smokeless tobacco at baseline was associated with 1.27-fold greater CVD incidence (95% confidence interval: 1.06, 1.52) than was nonuse, independently of demographic, socioeconomic, and lifestyle and other tobacco-related variables. Past use of smokeless tobacco was not associated with CVD incidence. In conclusion, current use of smokeless tobacco was associated with increased risk of CVD incidence in ARIC cigarette nonsmokers. Current users of smokeless tobacco should be informed of its harm and advised to quit the practice. Current cigarette smokers should also be given sufficient information on safe, therapeutic methods of quitting which do not include switching to smokeless tobacco.