Systematic review of determinants and interventions of areca nut cessation: curbing a public health menace.

BACKGROUND: Areca nut (AN) is a proven human carcinogen and a global public health menace. There is yet no review providing comprehensive information on the determinants and interventions available for cessation of AN. This systematic review was aimed at summarizing the available literature on drivers and interventions for cessation of AN chewing habit and to highlight the research lacunae. METHODS: A systematic literature search (from 1990 till March 2021) was conducted for studies on AN cessation. Relevant data were extracted independently by two authors. RESULTS: A total of 16 studies were included, which highlighted the influence of socio-cultural factors, addictive nature of AN and withdrawal symptoms as barriers to quitting. However, the knowledge of ill-effects of AN use on health, absence of concurrent alcohol use or smoking and family pressure were associated with likelihood of AN cessation. The interventions utilized for AN cessation have been behavioural in majority of the studies except for one where antidepressants were used for this purpose. CONCLUSIONS: The current review emphasizes the imperative need of appropriate cessation strategies for AN chewing habit including enhancing awareness of the harmful effects and research into additional behavioural and pharmacologic cessation therapies to control this significant public health problem.

Dual Burden of Smoked and Smokeless Tobacco Use in India, 2009-2017: A Repeated Cross-Sectional Analysis Based on Global Adult Tobacco Survey.

INTRODUCTION: The dual use of smoked and smokeless tobacco (SLT) poses a serious challenge to tobacco control efforts. This article examines the trends and patterns of this usage in India during the period 2009-2010 and 2016-2017. METHODS: Data from two rounds of nationally representative cross-sectional Global Adult Tobacco Survey (GATS) conducted in 2009-2010 and 2016-2017 have been used. Dual use was assessed based on current smokers and SLT users in both rounds. RESULTS: Findings reveal that dual use in India has dropped from 5.3% during 2009-2010 to 3.4% during 2016-2017, a decline of nearly 10 million dual users. However, some states have added nearly 4.6 million new dual users during this period. While dual use continues to remain high in rural areas, there has been a manifold increase in urban areas. Findings revealed that intention to quit tobacco was lower among dual tobacco users as compared to single users with considerable difference between urban and rural areas. CONCLUSION: Easy availability and affordability of SLT products compared to smoking products and restrictions on smoking in public places may have pushed current smokers and dual users to take to or intensify their SLT consumption. Measures relating to awareness, pricing, taxation, and enforcement of tobacco control laws should focus on all forms of tobacco, especially targeting high dual burden in rural and urban settings. IMPLICATIONS: Dual form of tobacco users represent 12% of all tobacco users in the country. The study reveals that intention to quit tobacco among dual users is significantly lower than that among single tobacco product users. This requires improving public awareness about the morbidity and mortality that arises from the use of all forms of tobacco products. Efforts to restrict the availability of tobacco products should focus on licensing the sale of all tobacco products. Reduction in dual tobacco use will not only result in multiplied health benefits but also help in achieving the Non-Communicable Diseases targets under the United Nations Sustainable Development Goals.

Chemistry, metabolism and pharmacology of carcinogenic alkaloids present in areca nut and factors affecting their concentration.

Areca Nut (AN), the seed of tropical palm tree Areca catechu, is a widely chewed natural product with estimated 600 million users across the world. Various AN products, thriving in the market, portray 'Areca nut' or 'Supari' as mouth freshener and safe alternative to smokeless tobacco. Unfortunately, AN is identified as a Group 1 human carcinogen by International Agency for Research on Cancer (IARC). Wide variation in the level of alkaloids, broadly ranging from 2 to 10 mg/gm dry weight, is observed in diverse variety of AN sold worldwide. For the first time, various factors influencing the formation of carcinogenic alkaloids in AN at various stages, including during the growth, processing, and storage of the nut, are discussed. Current review illustrates the mechanism of cancer induction by areca alkaloids in humans and also compiles dose-dependent pharmacology and toxicology data of arecoline, the most potent carcinogenic alkaloid in AN. Careful monitoring of the arecoline content in AN can potentially be used as a tool in product surveillance studies to identify the variations in characteristics of various AN sample sold worldwide. The article will help to generate public awareness and sensitize the government bodies to initiate campaigns against AN use and addiction.

Smokeless tobacco control in 180 countries across the globe: call to action for full implementation of WHO FCTC measures.

Smokeless tobacco is consumed by 356 million people globally and is a leading cause of head and neck cancers. However, global efforts to control smokeless tobacco use trail behind the progress made in curbing cigarette consumption. In this Policy Review, we describe the extent of the policy implementation gap in smokeless tobacco control, discuss key reasons on why it exists, and make recommendations on how to bridge this gap. Although 180 countries have agreed that the WHO Framework Convention on Tobacco Control is the best approach to control the demand and supply of smokeless tobacco, only 138 (77%) Parties define smokeless tobacco in their statutes. Only 34 (19%) Parties tax or report taxing smokeless tobacco products, six (3%) measure content and emissions of smokeless tobacco products, and 41 (23%) mandate pictorial health warnings on these products. Although awareness of the harms related to smokeless tobacco is growing in many parts of the world, few Parties collect or present data on smokeless tobacco use under global or national surveillance mechanisms (eg, Global Tobacco Surveillance System and WHO STEPwise). Only 16 (9%) Parties have implemented a comprehensive ban on smokeless tobacco advertisement, promotion, and sponsorships. Globally, a smaller proportion of smokeless tobacco users are advised to quit the use of smokeless tobacco products compared to tobacco users. Use of smokeless tobacco is becoming a global cause of concern, requiring a greater commitment on the full implementation of the WHO Framework Convention on Tobacco Control measures.

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.

Association of Smokeless Tobacco Use and Oral Cancer: A Systematic Global Review and Meta-Analysis.

INTRODUCTION: Smokeless tobacco products have been linked to precancerous and cancers of oral cavity for long. Evidence was available on the association between smokeless tobacco (SLT) products and oral cancers at regional but not at global level. Present meta-analysis is aimed to evaluate the risk of oral cancer with the use of SLT products among "ever" versus "never" users. METHOD: Studies published for the period (1960-2016) are retrieved using Pubmed, Indmed, EMBASE, and Google Scholar search engines for the subject "ever" versus "never" users of SLT products and estimated the risk association with oral cancer. Summary odds ratios (relative risk) are estimated and meta-analysis was performed using random-effects model. RESULTS: Thirty-seven studies from four of six WHO regions, Southeast Asia region (SEAR), the Eastern Mediterranean Region (EMR), Europe, and region of Americas (North and South) are included in the analysis. Significant risk with SLT products with oral cancer was found for SEAR (4.44, 95% CI = 3.51 to 5.61) and for EMR (1.28, 95% CI = 1.04 to 1.56). Significantly higher risk (p < .001) was found for females (5.83, 95% CI = 2.93 to 11.58). Product wise analysis for different SLT products revealed various levels of risk viz. gutkha (8.67, 95% CI = 3.59 to 20.93), pan tobacco / betel liquid (7.18, 95% CI = 5.48 to 9.41), oral snuff (4.18, 50% CI = 2.37 to 7.38), Mainpuri tobacco (3.32, 95% CI = 1.32 to 8.36), and snus (0.86, 95% CI = 0.58 to 1.29). CONCLUSION: A significant positive association was observed between SLT use and the risk of oral cancer, in SEAR, EMRs, and among women users. IMPLICATIONS: The present meta-analysis demonstrates SLT product use and the risk of oral cancer at global level. Moreover, the present analysis provided data on the risk associated with individual SLT product. The results fulfil the gap in the data on independent effect of individual SLT product use on the outcome of oral cancer at global level, conclusively. Chewing SLT products was associated with higher risk of oral cancer than other types of SLT. This can serve as a useful tool for policy makers in forming strict policies in controlling SLT menace. Hence, we propose that in addition to smoking, efforts should be directed towards SLT product cessation as well in reducing oral cancer incidence.

Smokeless Tobacco Use is "Replacing" the Smoking Epidemic in the South-East Asia Region.

Background: The sustained anti-tobacco campaign initiated in response to the mounting evidence against tobacco smoking has driven tobacco companies and smokers to look for alternative choices, such as smokeless tobacco (SLT) products. If this strategy advances, it could undermine several gains made by the campaign over the years. Our objective was to examine the trends in the prevalence of different tobacco types in three countries (Bangladesh, India, and Nepal) of South-East Asia. Methods: Data from national surveys were used to estimate the trends of weighted and age-standardized prevalence (along with 95% CI) of different tobacco products. The share of each tobacco type was then calculated as a percentage of total tobacco use for each time point and country. Results: In all the three countries, smoking prevalence declined (by 6% in Bangladesh, 3% in India, and 7% in Nepal) but SLT use increased (by 3% in Bangladesh, 6% in India, and 4% in Nepal) over the study period. SLT use increased irrespective of whether the total tobacco use increased or decreased. The share of SLT as a percentage of total tobacco use increased from 15% to 19% among Bangladeshi men, from 46% to 61% in India, and from 29% to 41% in Nepal. Conclusions: In South-East Asia, a clear shift in the product preference from smoking to SLT was noted. Misleading advertising by tobacco companies may be responsible for the increase in the SLT prevalence, which is as harmful as smoking. Countries should strengthen policies to restrict SLT usage and prevent the rise of its use. Implications: It has been documented that the smoking prevalence has been declining in most countries of the South-East Asia region where effective anti-tobacco laws have been implemented. But, due to a number of factors, the prevalence of smokeless tobacco has been increasing steadily, making the entire anti-tobacco movement less effective in terms of reducing the tobacco-attributable disease burden. In this context, this study has provided a detailed comparative analysis of the prevalence of smokeless tobacco use and smoking in three countries of the SEAR where such data were available. It can be clearly seen that the preference for smoking has shifted towards the smokeless tobacco in all the three study countries. This study recommends that tobacco control interventions should be aligned with the changing dynamics of the tobacco epidemic, and the need of the hour is placing restrictions of smokeless tobacco use so as to drive forward the gains of the anti-tobacco movement.

The changing face of risk factors for non-communicable disease in Myanmar: findings from the 2009 and 2014 WHO STEP Surveys.

BACKGROUND: Myanmar is burdened with the dual problem of communicable and non-communicable diseases (NCD), and is constantly endeavoring to attain its health objectives with limited resources. This study compares the results for the 2009 and 2014 WHO STEPs surveys (the 'stepwise' approach to adult risk factor surveillance) in Myanmar to determine the change in NCD risk factors over time. METHODOLOGY: The proportion of individuals with major NCD risk factors such as current tobacco and alcohol consumption, <5 fruit/vegetable servings, physical activity, raised blood pressure (BP) and overweight and obesity from the year 2009 (n = 6414) and year 2014 (n = 8757) WHO STEP surveys were compared for the age group 25-64 and relative changes (RC) calculated. RESULTS: Tobacco and alcohol consumption has increased significantly (25 and 49% RC, respectively) over the years. Individuals with low fruit/vegetable consumption (<5 servings) have declined (4.3% RC) and physical activity has increased significantly (46.5% RC). The prevalence of overweight, obese and hypertensive individuals has reduced significantly during this period with a RC reduction of 18, 28 and 20%, respectively. CONCLUSION: Reductions in some NCD risk factors are encouraging but control of tobacco use and alcohol consumption requires more stringent policies in order to prevent NCDs in the future.

The Poorest of Poor Suffer the Greatest Burden From Smokeless Tobacco Use: A Study From 140 Countries.

Background: The full extent of global smokeless tobacco (SLT) use and its association with key demographic factors such as gender, place of residence, and household or country income status is not yet known. Methods: The global burden of SLT use among adults was estimated using nationally representative data of 140 countries by gender and country income group. Countries were grouped in Group 1 (low and low-middle income countries combined) and Group 2 (upper middle and high income countries combined). The number of male and female SLT users was calculated using prevalence and population estimates of corresponding age groups. Results: Nearly one in 10 males and one in 20 females used SLT in some form. SLT use prevalence was significantly higher among males (p < .001) and females (p < .001) in Group 1 countries compared with their counterparts in Group 2 countries. However, for both Group 1 (p < .01) and Group 2 (p < .01), males were more likely to use SLT than females. Nearly 91% of a total 356 million adult SLT users resided in Group 1 countries, with 81.6% in countries of WHO South-East Asia region (SEAR). In SEAR and African region, SLT use was higher in rural areas and poorest communities. Conclusion: The majority of the burden of SLT use is on lower and lower middle income countries with the greatest burden on the poorest segments of the population in these countries. Implications: This study brings the comprehensive information on epidemiology of SLT use among adults at global level. Ninety percent of SLT burden is in low and low-middle income group of countries and more specifically among the poorest group in such countries. These countries need to have strategies to implement different provisions of the WHO Framework Convention on Tobacco Control. The program in such countries should be targeted towards the poorest communities for effective SLT control.

Global burden of all-cause and cause-specific mortality due to smokeless tobacco use: systematic review and meta-analysis.

OBJECTIVES: To systematically review and meta-analyse the studies investigating the association between smokeless tobacco (SLT) use and all-cause mortality and cause-specific mortality outcomes among adult users of SLT and estimate the number of attributable deaths worldwide. METHODS: Random-effects meta-analysis was used to estimate the pooled risk of death due to SLT use. Population attributable fractions were derived and used to calculate the number of attributable deaths. Observational studies published upto 2015 were identified through MEDLINE, IndMED, Google Scholar and other databases. Data on the prevalence of SLT use was obtained from latest reports or national surveys. Data on the disease burden were obtained from the Global Burden of Disease Study. Hospital-based or community-based case-control and cohort studies that adjusted for the smoking status were included. RESULTS: 16 studies that provided estimates for mortality due to all cause, all cancer, upper aerodigestive tract (UADT) cancer, stomach cancer, cervical cancer, ischaemic heart disease (IHD) and stroke were included. A significant association was found for mortality due to all cause (1.22; 1.11-1.34), all cancer (1.31; 1.16-1.47), UADT cancer (2.17; 1.47-3.22), stomach cancer (1.33; 1.12-1.59), cervical cancer (2.07; 1.64-2.61), IHD (1.10; 1.04-1.17) and stroke (1.37; 1.24-1.51). Subgroup analysis showed major regional differences. Globally, the number of attributable deaths from all-cause mortality was 652 494 (234 008-1 081 437), of which 88% was borne by the South-East Asian region. CONCLUSIONS: SLT is responsible for a large number of deaths worldwide with the South-East Asian region bearing a substantial share of the burden.

Relationship between type of smokeless tobacco & risk of cancer: A systematic review.

BACKGROUND & OBJECTIVES: Causative linkages of smokeless tobacco (SLT) use with oral potentially malignant disorders and cancers of oral cavity, oesophagus and pancreas have been reported. Published meta-analyses have provided pooled risk estimates for major cancers caused by SLT, both on global and regional levels. This systematic review was aimed at summarizing the available studies on occurrence and mortality risk of common cancers due to various SLT products. METHODS: PubMed and Google Scholar databases were systematically searched from 1985 till January 2018 for observational studies on SLT and cancer. The included studies were evaluated and data were extracted and reviewed. RESULTS: The review included 80 studies providing 121 risk estimates for various cancers. Majority of the studies from South-East Asian Region (SEAR) and Eastern Mediterranean Region (EMR) showed a significant positive association of SLT use with oral [odds ratio (OR) ranging from 1.48 to 27.4] and oesophageal cancers (OR between 2.06 and 12.8), while studies from European Region (EUR) reported a positive association with pancreatic cancer (OR between 1.6 and 2.1). Cancer-related mortality was evaluated in a few reports with higher risk of mortality for lung (OR between 2.0 and 9.1), cervical (OR 2.0) and prostate (OR 2.1) cancers. A wide variation was noted in the association of various cancers and specific SLT products based on their nature, methods of use and inherent toxicity. The majority of chewing tobacco products displayed higher risk for oral and oesophageal cancers while the same was not observed for snus. INTERPRETATION & CONCLUSIONS: This review emphasizes on the significantly positive association of SLT use with oral and oesophageal cancers in SEAR and EMR and pancreatic cancer in EUR. Mortality estimates for SLT-associated cancers need further analysis. Risk analysis for cancers of other sites in SLT users also requires multicentric well-designed studies.

Smokeless tobacco taxation: Lessons from Southeast Asia.

Southeast Asia accounts for nearly 86 per cent of the smokeless tobacco (SLT) consumers in the world. The heterogeneous nature of SLT is a major impediment to using taxation as a tool to regulate SLT. This study was aimed to review issues around fiscal policies on SLT with the objective of providing clarity on the use of taxation as an effective policy instrument to regulate SLT use. Descriptive statistics and graphical representations were used to analyze published data from different sources. An analysis of prices and tax between smoke and SLT products was done to understand the impact of tax policies on SLT consumption. India, Bangladesh and Myanmar together account for 71 per cent of the world SLT users. The retail prices (PPP$) and tax were lower for SLT in low- and lower-middle-income countries and higher in high-income countries, on an average, suggesting a direct relationship between the two. Evidence from India and Bangladesh suggested that taxation had significantly reduced SLT use among adults. The compounded levy scheme used in India to tax SLT was found effective after incorporating speed of packing machines into the assessment of deemed production and tax on SLT products. The current analysis shows that taxation can be an effective instrument to regulate SLT consumption if tax rates are harmonized across SLT products and in a manner not to encourage substitution with other tobacco products. It is also imperative to set a minimum floor price on all tobacco products including SLT.

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.

A review of trade practices of smokeless tobacco products in terms of prohibition on sale, manufacturing & importation in Framework Convention on Tobacco Control ratified Parties.

BACKGROUND & OBJECTIVES: Over the past decade, the World Health Organization (WHO) Framework Convention on Tobacco Control (FCTC) has served as a powerful tool to initiate and advance global tobacco control efforts. However, the control strategies have mainly targeted demand-side measures. The goal of a tobacco-free world by 2040 cannot be achieved if the supply-side measures are not addressed. This analysis was undertaken to examine the tobacco control legislations of various Parties ratifying WHO FCTC with an objective to ascertain the status of prohibition of importation, sale and manufacturing of smokeless tobacco products. METHODS: All 180 Parties to WHO FCTC were included for the study. A comprehensive database of all the parties to FCTC was created and tobacco control legislations and regulations of all parties were studied in detail. RESULTS: Overall, the sale of smokeless tobacco (SLT) products was prohibited in 45 Parties. Eleven Parties prohibited manufacturing of SLT products and six Parties imposed a ban on importation of SLT products. Australia, Bhutan, Singapore and Sri Lanka banned all three. INTERPRETATION & CONCLUSIONS: Comprehensive tobacco control strategy with effective tobacco cessation programme should complement strong legal actions such as prohibition on trade in SLT products to meet the public health objective of such laws and regulations. In addition, multisectoral efforts are needed for effective implementation of such restrictions imposed by the governments.

In-silico study of toxicokinetics and disease association of chemicals present in smokeless tobacco products.

Smokeless tobacco (SLT) products are consumed by millions of people in over 130 countries around the world. Consumption of SLT has been estimated to cause a number of diseases accounting to more than 0.65 million deaths per year. There is sufficient epidemiological evidence on the association of SLT products with nicotine addiction, cancers of oral cavity and digestive systems but there is a lack of understanding of the role of toxic chemicals in these diseases. We provide the first comprehensive in-silico analysis of chemical compounds present in different SLT products used worldwide. Many of these compounds are found to have good absorption, solubility and permeability along with mutagenic and toxic properties. They are also found to target more than 350 human proteins involved in a plethora of human biological processes and pathways. Along with all the previously known diseases, the present study has identified the association of compounds of SLT products with a number of unknown diseases like neurodegenerative, immune and cardiac diseases (Left ventricular non compaction, dilated cardiomyopathy etc). These findings indicate far-reaching impact of SLT products on human health than already known which needs further validations using epidemiological, in-vitro and in-vivo methodologies. Thus, this study will provide one stop information for the policy makers in development of regulatory policies on toxic contents of SLT products.

Smokeless tobacco and public health in Bangladesh.

Despite the high prevalence of smokeless tobacco (SLT) use among adults in Bangladesh, SLT was not included in the Tobacco Control Law till 2013. Information on SLT use among Bangladeshi people is inadequate for policymaking and implementing effective control measures. With the aim to identify the prevalence and trends of different SLT products, health and economic impacts, manufacture, and sale of and policies related to SLT in Bangladesh, we carried out a literature review, which involved literature search, data extraction, and synthesis. Evidence suggests that in Bangladesh, SLTs range from unprocessed to processed or manufactured products including Sada Pata, Zarda, Gul, and Khoinee. Over 27% of Bangladeshi adults aged 15 years and older use SLT in one form or other. SLT use is associated with age, sex, education, and socioeconomic status. SLT consumption has reportedly been associated with increased prevalence of heart diseases, stroke, and oral cancer and led to around 320,000 disability adjusted life years lost in Bangladesh in 2010. No cessation service is available for SLT users in public facilities. Compared to cigarettes, taxation on SLT remains low in Bangladesh. The amendment made in Tobacco Control Law in 2013 requires graphic health warnings to cover 50% of SLT packaging, ban on advertisement of SLT products, and restriction to sale to minors. However, implementation of the law is weak. As the use of SLT is culturally accepted in Bangladesh, culturally appropriate public awareness program is required to curb SLT use along with increased tax and cessation services.

Smokeless tobacco-associated cancers: A systematic review and meta-analysis of Indian studies.

The International Agency for Research on Cancer (IARC) has concluded that there is sufficient evidence in humans for the carcinogenicity of smokeless tobacco (SLT) for mouth, oesophagus and pancreas, based largely on Western studies. We wanted to confirm this by conducting a systematic review using Indian studies because India faces the biggest brunt of SLT-attributable health effects. A systematic search was conducted for published and unpublished studies. Two authors independently reviewed the studies and extracted data. Summary odds ratio (OR) for each cancer type was calculated using fixed and random effects model. The population attributable fraction (PAF) method was used to calculate the attributable burden of incident cases. A significant association was found for oral-5.55 (5.07, 6.07), pharyngeal-2.69 (2.28, 3.17), laryngeal-2.84 (2.18, 3.70), oesophageal-3.17 (2.76, 3.63) and stomach-1.26 (1.00, 1.60) cancers. But in random effects model, laryngeal-1.79 (0.70, 4.54) and stomach-1.31 (0.92, 1.87) cancers became non-significantly associated. Gender-wise analysis revealed that women had a higher risk (OR = 12.0 vs. 5.16) of oral but a lower risk (1.9 vs. 4.5) of oesophageal cancer compared with men. For oral cancer, studies that adjusted for smoking, alcohol and other factors reported a significantly lower OR compared with studies that adjusted for smoking only or smoking and alcohol only (3.9 vs. 8.4). The annual number of attributable cases was calculated as 49,192 (PAF = 60%) for mouth, 14,747 (51%) for pharynx, 11,825 (40%) for larynx, 14,780 (35%) for oesophagus and 3,101 (8%) for stomach.

Prevalence and Sociodemographic Determinants of Any Tobacco Use and Dual Use in Six Countries of the WHO South-East Asia Region: Findings From the Demographic and Health Surveys.

BACKGROUND: Tobacco control is an important strategy to reduce the disease burden caused by several noncommunicable diseases. An in-depth understanding of the sociodemographic variations in tobacco use is an important step in achieving effective tobacco control. AIMS: We aimed to estimate the age-standardized prevalence of any tobacco use and dual tobacco use and determine their association with sociodemographic variables in six countries (Bangladesh, Indonesia, India, Maldives, Nepal, and Timor Leste) of the WHO South-East Asia Region. METHODS: The main outcome variables "any tobacco use" and "current dual use" were created from the latest available Demographic and Health Surveys data for each country. The prevalence estimates were weighted using sample weights and age standardized using the WHO standard population. Associations between the sociodemographic variables and tobacco use were calculated by performing multivariable logistic regression analysis. Analyses were performed in Stata 12 using "svyset" and "svy" commands. RESULTS: The highest prevalence of any tobacco use among men was in Indonesia (76.4%) and among women in Nepal (15.7%). Also, Nepal had the highest prevalence of dual tobacco use in both men (17.9%) and women (1.5%). With regard to sociodemographic determinants, despite the inter-country variations, any and dual tobacco use were significantly associated with age, higher education, greater wealth, rural residence, and ever-married marital status. The poor and uneducated had a higher odds ratio for these practices. CONCLUSION: Prevalence of dual tobacco use and its underlying socioeconomic disparities should be taken into account for the planning of tobacco control activities in the region. IMPLICATIONS: The dual tobacco use phenomenon is being increasingly recognized as a distinct entity in the fight against tobacco addiction. When compared with single product users, dual users have a greater risk of developing tobacco related diseases and are less likely to quit their habits. However, this phenomenon has not been studied adequately in the South-East Asia region. In this context, this study has provided a detailed and comprehensive view of dual tobacco use and its sociodemographic determinants in six countries of the region. This study recommends that tobacco control interventions should be targeted specifically at the disadvantaged sections of the society, such as the poor and the uneducated, who are more likely to engage in "dual" as well as "any" tobacco use. This study could prove as an important reference and tool for policy making in the South-East Asia region.

Awareness and Current Use of Electronic Cigarettes in Indonesia, Malaysia, Qatar, and Greece: Findings From 2011-2013 Global Adult Tobacco Surveys.

INTRODUCTION: Increases in electronic cigarette (e-cigarette) awareness and current use have been documented in high income countries but less is known about middle and low income countries. METHODS: Nationally representative household survey data from the first four Global Adult Tobacco Surveys to assess e-cigarettes were analyzed, including Indonesia (2011), Malaysia (2011), Qatar (2013), and Greece (2013). Correlates of e-cigarette awareness and current use were calculated. Sample sizes for Greece and Qatar allowed for further analysis of e-cigarette users. RESULTS: Awareness of e-cigarettes was 10.9% in Indonesia, 21.0% in Malaysia, 49.0% in Qatar, and 88.5% in Greece. In all four countries, awareness was higher among male, younger, more educated, and wealthier respondents. Current e-cigarette use among those aware of e-cigarettes was 3.9% in Malaysia, 2.5% in Indonesia, 2.2% in Greece and 1.8% in Qatar. Across these four countries, an estimated 818 500 people are currently using e-cigarettes. Among current e-cigarette users, 64.4% in Greece and 84.1% in Qatar also smoked cigarettes, and, 10.6% in Greece and 6.0% in Qatar were never-smokers. CONCLUSIONS: E-cigarette awareness and use was evident in all four countries. Ongoing surveillance and monitoring of awareness and use of e-cigarettes in these and other countries could help inform tobacco control policies and public health interventions. Future surveillance should monitor use of e-cigarettes among current smokers and uptake among never-smokers and relapsing former smokers.