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Drug and Alcohol Review (January 2014), 33, 86–92 DOI: 10.1111/dar.12074
Smokeless tobacco consumption in the South Asian population of Sydney, Australia: prevalence, correlates and availability MOHAMMAD SHAKHAWAT HOSSAIN1, KYPROS KYPRI1, BAYZIDUR RAHMAN2 & ABUL HASNAT MILTON1 1
School of Medicine and Public Health, Faculty of Health and Medicine, The University of Newcastle, Newcastle, Australia, and 2School of Public Health and Community Medicine, University of New South Wales, Sydney, Australia
Abstract Aim. The aim of this study was to estimate the prevalence and identify correlates of smokeless tobacco consumption among the South Asian residents of Sydney, Australia. Methods. A cross-sectional survey was conducted using a pretested, selfadministered mailed questionnaire among members of Indian, Pakistani and Bangladeshi community associations in Sydney. Results. Of 1600 individuals invited to participate, 419 responded (26%). Prevalence rates of ever consumption, more than 100 times consumption and current consumption were 72.1%, 65.9% and 17.1%, respectively. Men (74.3%) were more likely to ever consume than women (67.6%). Over 96% of consumers reported buying smokeless tobacco products from ethnic shops in Sydney. Current consumption of smokeless tobacco products was associated with country of birth: Indians (odds ratio 5.7, 95% confidence interval 2.3–14.5) and Pakistanis (odds ratio 3.1, 95% confidence interval 1.5–6.5) were more likely to be current consumers than Bangladeshis after adjusting for sociodemographic variables. For ever consumption, there was a positive association with age (P for trend = 0.013) and male gender (odds ratio 2.1, 95% confidence interval 1.5–3.1). Conclusions. Given the availability of smokeless tobacco and the high prevalence and potential adverse health consequences of consumption, smokeless tobacco consumption may produce a considerable burden of non-communicable disease in Australia. Effective control measures are needed, in particular enforcement of existing laws prohibiting the sale of these products. [Hossain MS, Kypri K, Rahman B, Milton AH. Smokeless tobacco consumption in the South Asian population of Sydney, Australia: prevalence, correlates and availability. Drug Alcohol Rev 2014;33:86–92] Key words: smokeless tobacco, chewing tobacco, Sydney, South Asian population.
Introduction Nearly six million people die each year as a result of tobacco use [1,2]. The World Health Organization estimates there were 100 million premature deaths globally due to tobacco use last century, and if the current trends in tobacco consumption continue, the death toll will be one billion this century [3]. Tobacco-related diseases are the leading cause of death in almost all countries [4]. To date, concern about tobacco consumption has centered mostly on smoking, and smokeless tobacco consumption (STC) has rarely been the subject of scientific investigation in Australia. Use of smokeless tobacco products is increasing in South Asia [5–7], a major source of immigration to Australia. Some Scandinavian and US studies suggest that smokeless tobacco products, such as snus and snuff, are
less harmful alternatives to smoking, but research evidence to support this contention remains inconclusive [6]. Many studies conducted in India, the UK and the USA indicate that STC causes cancer of the oral cavity [6,8–10], throat, head and neck [5,11]. It also increases the risk of pancreatic cancer, diabetes, metabolic disease and cardiovascular disease [6,9]. Additionally, STC is a risk factor for stroke, high cholesterol and adverse pregnancy outcomes [12–14]. STC is common among South Asian people, including women [13,15,16]. More than one-third of total tobacco consumption in South Asia is in the form of smokeless tobacco [13,15]. The World Health Organization estimates there are nearly 250 million adult smokeless tobacco users in its South-East Asia region (including 26 million in Bangladesh), representing 90% of global smokeless tobacco consumers [5,17–20].
Correspondence to Dr Abul Hasnat Milton, School of Medicine and Public Health, Faculty of Health and Medicine,The University of Newcastle, NSW 2308, Australia. Tel: +61 2 4042 0525; Fax: +61 2 4042 0044; E-mail: [email protected] Received 1 April 2013; accepted for publication 10 September 2013. © 2013 Australasian Professional Society on Alcohol and other Drugs
Smokeless tobacco consumption in Sydney
In some parts of South Asia, such as Bihar and Maharashtra in India, one in three people uses smokeless tobacco, making it more popular than smoking [5,21]. It has also been shown that chewing of betel quid containing tobacco is common among Bangladeshi, Indian and Pakistani immigrants in the UK [5,21–23]. In Bangladesh, India and Pakistan, traditional values and social norms do not favor smoking by the young or by women, but there is no such taboo against STC [5]. The prevalence of smoking among women (1.5%) is very low compared with men (44.7%), whereas STC is almost equally common among women (27.9%) and men (26.4%) in Bangladesh [17]. STC is related to traditional values, spirituality, beliefs, festivals, and rituals, such as marriage [5]. Its perceived medicinal value for curing toothache, headache and stomachache leads many adults to become users, and some parents even encourage their children to use smokeless tobacco [5]. The types of smokeless tobacco products in use vary by region: snus in Europe, gutka and zarda in Asia and toombak in Africa [5,15,21–23]. Generally, sun- or aircured smokeless tobacco can be used by itself in unprocessed, processed or manufactured form [7]. Smokeless tobacco is also consumed as a component of betel quid, which is a combination with lime, areca nut and other ingredients [19]. There are various forms of smokeless tobacco in South Asia, such as zarda, gutka, Paan masala, Paan parag, tobacco with lime (calcium oxide), tobacco with areca nut, tobacco tooth powder (gul) and dried tobacco leaves [5,13,15,22]. Even within regions, there are differences in types of product that make it difficult to assess the severity of risks they pose. There are a large number of South Asian migrants in Sydney, Australia, and many more will migrate there in future.We hypothesised that a substantial proportion of South Asian ethnic residents of Sydney consume smokeless tobacco products. The aim was to estimate the prevalence of STC in these populations and its association with sociodemographic variables. Methods Design We conducted a cross-sectional survey. Sampling The participants were Australian citizens with Indian, Bangladeshi or Pakistani ethnic background living in the Sydney metropolitan area. We gained the cooperation of the Bangladesh Association of New South Wales, United Indian Associations and Pakistan Association of Australia in order to develop a sampling frame. We
87
initially communicated with the office bearers of these community organisations and explained the objectives and proposed methods of the study to them. They provided lists of eligible and easily identified members, from which we randomly selected samples.The number selected from each ethnic group was based on probability proportionate to size. A sample of 400 participants is sufficient to estimate a 50% prevalence of STC with 95% confidence interval of width ± 5%. In the absence of published prevalence estimates, we conservatively assumed a 50% prevalence of smokeless tobacco consumption. Assuming a response rate of 25%, we selected a total of 1600 of 6386 people from the three communities, i.e. 400/1605, 800/3198 and 400/1583 individuals with Bangladeshi, Indian and Pakistani background, respectively, from all eligible members. Measurement The questionnaire was designed to collect information on STC, product availability and knowledge and attitudes about STC, as well as sociodemographic information, such as age, gender, marital status, income, employment, education, country of birth and religion. ‘Ever consumption’ was defined as having ever consumed smokeless tobacco products in the respondent’s lifetime. ‘Consumed more than 100 times’ was defined as consumption of smokeless tobacco products at least 100 times in the respondent’s lifetime. ‘Current consumption’ was defined as having consumed smokeless tobacco products more than 100 times in the respondent’s lifetime and at least once-daily use in the preceding six months. Procedure In October 2010 we mailed a package containing an introductory letter, study information sheet and questionnaire, all in English, to all participants. Participants were asked to read the information sheet carefully. If the participant agreed to participate he or she completed the questionnaire and returned it in a postagepaid return envelope. Two hundred and seventy-two (17%) respondents completed and returned their questionnaire within three weeks. After four weeks, each non-respondent was sent a reminder by mail. The first author attended community meetings and made formal announcements about the project, inviting members to participate. In the following three weeks another 147 sample members (9%) completed and returned questionnaires. Ethical approval The University of Newcastle’s Human Research Ethics Committee approved the study (H-2011-0131). © 2013 Australasian Professional Society on Alcohol and other Drugs
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Statistical analyses Independent-sample t-tests and one-way anova were used to estimate P values for differences in STC by age and gender. Categorical variables were reported as proportions, while continuous variables were summarised with means and standard deviations when distributions were approximately normal. Prevalence of STC was estimated as a proportion, and χ2-tests and t-tests were used to compare the demographic characteristics of current consumers, more-than-100-times consumers and ever consumers. Associations between STC and the exposures of interest were investigated using simple and multiple logistic regression. All the analyses were adjusted for the design effect using svy set in Stata 11 (StataCorp, College Station, TX, USA). To construct the final multivariate model, we adopted a backward elimination method. Any variable
that was significant at the 15% level in the univariate model was included in the base model. Association with the main exposure variable was estimated after adjusting for confounders and effect modifiers. The final model was based on the statistical significance of the covariates.We retained all the variables significant at the 5% level in the multivariate model. We excluded variables from the base model using backward elimination based on their P value, starting with the variable with the highest P value greater than 0.05.
Results Characteristics of the study participants The demographic characteristics of the study participants are presented in Table 1. A total of 419 individuals participated (response rate 26%), including 274
Table 1. Demographic characteristics of the study participants Country of birth
Variable Age (years) Mean Standard deviation Gender, n (%) Male Female Education, n (%) Postgraduate Undergraduate Non-tertiary (0 to12 years) Missing Religion, n (%) Muslim Hindu Others Missing Income per weekb, n (%) A$1000 Missing Employment, n (%) Business Full-time (>35 h) Part-time Looking for a job Missing Marital status, n (%) Married Unmarried Others
Bangladesh n = 139
India n = 150
Pakistan n = 130
37.4 8.91
39.1 5.92
38.3 5.30
90 (64.8) 49 (35.3)
87 (58.0) 63 (42.0)
97 (74.6) 33 (25.4)
0.014
274 (65.4) 145 (34.6)
54 (38.8) 64 (46.1) 21 (15.1) 0 (0.0)
53 (35.3) 41 (27.3) 48 (32.0) 8 (5.41)
46 (35.4) 36 (27.7) 32 (24.6) 16 (12.3)
0.002
153 (35.5) 141 (33.7) 101 (24.1) 24 (5.70)
91 (65.5) 41 (29.5) 6 (4.30) 1 (0.70)
6 (4.00) 124 (82.7) 13 (8.70) 7 (4.60)
125 (96.2) 0 (0) 2 (1.50) 3 (2.30)
100 times Current consumption n = 294 P value n = 199 P value n = 48 P value 294/408 (72.1) (67.4–76.4)
199/302 (65.9) (60.1–71.1)
48/281 (17.1) (12.9–22.0)
54/112 (48.2) 188/233 (80.7) 52/63 (82.5)
$AUD1000 $AUD500 to 1000 35 h) Part-time Looking for a job Marital status Unmarried Married Others
Ever consumption n = 294
Consumed >100 times n = 199
1 2.73 (1.70–4.31) 3.32 (2.71–3.92) 0.013
1 0.62 (0.12–4.41) 0.42 (0.13–1.82) 0.02
1 0.51 (0.13–2.11) 2.14 (0.43–10.5) 0.18
1 2.13 (1.51–3.13)
1 1.91 (1.04–3.81)
1 1.51 (0.83–2.82)
1 0.62 (0.22–1.80) 0.70 (0.23–2.04) 0.78
1 1.34 (0.21–10.6) 0.83 (0.23–3.14) 0.60
1 1.74 (0.52–5.91) 2.9 (0.24–41.7) 0.38
1 1.24 (0.13–19.4) 0.84 (0.13–6.64)
1 0.91 (0.23–3.11) 1.62 (0.33–9.01)
1 5.72 (2.30–14.52) 3.14 (1.51–6.50)
1 0.71 (0.14–92.2) 1.53 (0.12–184.1)
1 2.20 (0.14–46.2) 1.31 (0.12−16.2)
1 0.71 (0.32–1.9) 1.62 (0.14–19.1)
1 0.98 (0.23–4.70) 3.96 (0.14–244.1)
1 0.41 (0.21–1.02) 3.9 (2.34–6736344)
1 1.44 (0.31–6.42) 1.13 (0.14–2198.9)
1 1.20 (1.12–1.32) 0.41 (0.13−0.82) 1.14 (0.13−80.5)
1 0.71 (0.41−1.24) 0.32 (0.12−10.4) 0.71 (0.21−2.23)
1 0.61 (0.32–1.13) 6.74 (0.14–464.1) 0.63 (0.13−710.1)
1 4.32 (0.14−151.7) 1.12 (0.43−3.5)
1 9.93 (0.14−15 505.5) 7.94 (0.13−147 744.7)
Current consumption n = 48
Not applicableb Not applicable Not applicable
a Adjusted for all variables shown in the table. bMarital status was excluded from the multivariate model because of its nonsignificant association with current consumption.
Australian research conducted in 2004 reported that 94% of South Asian grocery shops in Sydney sell smokeless tobacco products, despite their sale being banned in Australia under the section 65C(7) of the Trade Practices Act 1974 [34]. In the first author’s experience of visiting shops in south-western Sydney, Paan masala, Paan parag and Baba zarda were visible on the shelves, while RMD gutka, Hakimpuri zarda and Raja khaini were hidden and had to be asked for. When asked if they knew that the sale of these products is illegal in Australia, most shopkeepers replied ‘yes’, but indicated that food inspectors and other authorities never asked about or commented on the matter. The findings underscore the need for restrictions on the availability of these products, firstly via enforcement
of existing legislation. It also highlights the need for education in South Asian ethnic groups in Australia on the health hazards of STC and for effective STC cessation programs [16,35]. In the short term there may be value in providing a low-cost intervention, such as feedback on the survey results, with leaflets informing respondents about the dangers of smokeless tobacco with advice to quit and access to cessation support services. Funding This research was conducted using a Research Training Scheme grant from the University of Newcastle, New South Wales, Australia. © 2013 Australasian Professional Society on Alcohol and other Drugs
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Acknowledgement The study would not have been possible without the cooperation of the office bearers of the Bangladesh Association of New South Wales, United Indian Associations and Pakistan Association of Australia in Sydney. Professor Kypros Kypri’s involvement was supported by a National Health and Medical Research Council research fellowship.
[17]
[18]
[19] [20] [21]
References [1] World Health Organization. Tobacco (Fact sheet No. 339). Geneva: World Health Organization, 2013. [2] Mishra GA, Pimple SA, Shastri SS. An overview of the tobacco problem in India. Indian J Med Paediatr Oncol 2012;33:139–45. [3] World Health Organization. The global tobacco epidemic. Geneva: World Health Organization, 2011. [4] World Health Organization. Global status report on noncommunicable diseases. Geneva: World Health Organization, 2010. [5] Gupta PC, Ray CS. Smokeless tobacco and health in India and South Asia. Respirology 2003;8:419–31. [6] U.S. National Cancer Institute,World Health Organization, U.S. Centers for Disease Control and Prevention, Danya International. International Smokeless Tobacco Symposium. Final report. Bethesda, MD: U.S. National Cancer Institute, 2009. [7] World Health Organization. Report on oral tobacco use and its implications in South-East Asia. NewYork: World Health Organization, 2004. [8] International Agency for Research on Cancer. Smokeless tobacco and some tobacco-specific N-nitrosamines. IARC Monogr Eval Carcinog Risks Hum 2007;89:1–592. [9] Pednekar MS, Gupta PC, Yeole BB, Hebert JR. Association of tobacco habits, including bidi smoking, with overall and site-specific cancer incidence: results from the Mumbai cohort study. Cancer Causes Control 2011;22:859–68. [10] Boffetta P, Hecht S, Gray N, Gupta PC, Straif K. Smokeless tobacco and cancer. Lancet Oncol 2008;9:667–75. [11] Zhou J, Michaud DS, Langevin SM, McClean MD, Eliot M, Kelsey KT. Smokeless tobacco and risk of head and neck cancer: evidence from a case–control study in New England. Int J Cancer 2013;132:1911–7. [12] Rogers JM. Tobacco and pregnancy: overview of exposures and effects. Birth Defects Res 2008;84:1–15. [13] Gupta PC, Subramoney S. Smokeless tobacco use and risk of stillbirth: a cohort study in Mumbai, India. Epidemiology 2006;17:47–51. [14] Marita B. Systematic review of the health effects of modified smokeless tobacco products. Christchurch, New Zealand: Department of Public Health and General Practice, Christchurch School of Medicine and Health Sciences, 2007. [15] Gupta PC, Subramoney S. Smokeless tobacco use, birth weight, and gestational age: population based, prospective cohort study of 1217 women in Mumbai, India. Br Med J 2004;328:1538–40. [16] Mukherjea A, Modayil MV. Culturally specific tobacco use and South Asians in the United States: a review of the
© 2013 Australasian Professional Society on Alcohol and other Drugs
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literature and promising strategies for intervention. Health Promot Pract 2013;14(5 Suppl):48S–60S. World Health Organization. Global Adult Tobacco Survey: Bangladesh report 2009. Dhaka: World Health Organization, 2009. World Health Organization. Global Adult Tobacco Survey (GATS): India. Mumbai: International Institute for Population Science, 2010. Singh PK. Tobacco control in the WHO South-East Asia Region. Indian J Cancer 2012;49:319–20. Gupta PC, Warnakulasuriya S. Global epidemiology of areca nut usage. Addict Biol 2002;7:77–83. Johnson N. Tobacco use and oral cancer: a global perspective. J Dent Educ 2001;65:328–39. Ahmed S, Rahman A, Hull S. Use of betel quid and cigarettes among Bangladeshi patients in an inner-city practice: prevalence and knowledge of health effects. Br J Gen Pract 1997;47:431–4. Kypri K, Samaranayaka A, Connor J, Langley JD, Maclennan B. Non-response bias in a web-based health behaviour survey of New Zealand tertiary students. Prev Med 2011;53:274–7. Meiklejohn J, Connor J, Kypri K. The effect of low survey response rates on estimates of alcohol consumption in a general population survey. PLoS ONE 2012;7:e35527. Daniel AB, Nagaraj K, Kamath R. Prevalence and determinants of tobacco use in a highly literate rural community in southern India. Natl Med J India 2008;21:163–5. Imam SZ, Nawaz H, Sepah YJ, Pabaney AH, Ilyas M, Ghaffar S. Use of smokeless tobacco among groups of Pakistani medical students—a cross sectional study. BMC Public Health 2007;7:231. Khawaja MR, Mazahir S, Majeed A, et al. Chewing of betel, areca and tobacco: perceptions and knowledge regarding their role in head and neck cancers in an urban squatter settlement in Pakistan. Asian Pac J Cancer Prev 2006;7:95– 100. Roth MA, Aitsi-Selmi A, Wardle H, Mindell J. Underreporting of tobacco use among Bangladeshi women in England. J Public Health 2009;31:326–34. Sinha DN, Gupta PC, Pednekar MS. Tobacco use among school personnel in eight North-eastern states of India. Indian J Cancer 2003;40:3–14. Bedi R, Gilthorpe MS. The prevalence of betel-quid and tobacco chewing among the Bangladeshi community resident in a United Kingdom area of multiple deprivation. Prim Dent Care 1995;2:39–42. Croucher R, Islam S, Jarvis M, et al. Tobacco dependence in a UK Bangladeshi female population: a cross-sectional study. Nicotine Tob Res 2002;4:171–6. Makwana NR, Shah VR, Yadav S. A study on prevalence of smoking and tobacco chewing among adolescents in rural areas of Jamnagar district, Gujarat state. J Med Sci Res 2007;1:47–9. Cavelaars AEJM, Kunst AE, Geurts JJM, et al. Educational differences in smoking: international comparison. BMJ 2000;320:1102–7. Sachdev P, Chapman S. Availability of smokeless tobacco products in South Asian grocery shops in Sydney, 2004. Med J Aust 2005;183:334. Ebbert J, Montori VM, Vickers-Douglas KS, Erwin PC, Dale LC, Stead LF. Interventions for smokeless tobacco use cessation. Cochrane Database Syst Rev 2007;(4): CD004306.
R E V I E W
Drug and Alcohol Review (January 2014), 33, 86–92 DOI: 10.1111/dar.12074
Smokeless tobacco consumption in the South Asian population of Sydney, Australia: prevalence, correlates and availability MOHAMMAD SHAKHAWAT HOSSAIN1, KYPROS KYPRI1, BAYZIDUR RAHMAN2 & ABUL HASNAT MILTON1 1
School of Medicine and Public Health, Faculty of Health and Medicine, The University of Newcastle, Newcastle, Australia, and 2School of Public Health and Community Medicine, University of New South Wales, Sydney, Australia
Abstract Aim. The aim of this study was to estimate the prevalence and identify correlates of smokeless tobacco consumption among the South Asian residents of Sydney, Australia. Methods. A cross-sectional survey was conducted using a pretested, selfadministered mailed questionnaire among members of Indian, Pakistani and Bangladeshi community associations in Sydney. Results. Of 1600 individuals invited to participate, 419 responded (26%). Prevalence rates of ever consumption, more than 100 times consumption and current consumption were 72.1%, 65.9% and 17.1%, respectively. Men (74.3%) were more likely to ever consume than women (67.6%). Over 96% of consumers reported buying smokeless tobacco products from ethnic shops in Sydney. Current consumption of smokeless tobacco products was associated with country of birth: Indians (odds ratio 5.7, 95% confidence interval 2.3–14.5) and Pakistanis (odds ratio 3.1, 95% confidence interval 1.5–6.5) were more likely to be current consumers than Bangladeshis after adjusting for sociodemographic variables. For ever consumption, there was a positive association with age (P for trend = 0.013) and male gender (odds ratio 2.1, 95% confidence interval 1.5–3.1). Conclusions. Given the availability of smokeless tobacco and the high prevalence and potential adverse health consequences of consumption, smokeless tobacco consumption may produce a considerable burden of non-communicable disease in Australia. Effective control measures are needed, in particular enforcement of existing laws prohibiting the sale of these products. [Hossain MS, Kypri K, Rahman B, Milton AH. Smokeless tobacco consumption in the South Asian population of Sydney, Australia: prevalence, correlates and availability. Drug Alcohol Rev 2014;33:86–92] Key words: smokeless tobacco, chewing tobacco, Sydney, South Asian population.
Introduction Nearly six million people die each year as a result of tobacco use [1,2]. The World Health Organization estimates there were 100 million premature deaths globally due to tobacco use last century, and if the current trends in tobacco consumption continue, the death toll will be one billion this century [3]. Tobacco-related diseases are the leading cause of death in almost all countries [4]. To date, concern about tobacco consumption has centered mostly on smoking, and smokeless tobacco consumption (STC) has rarely been the subject of scientific investigation in Australia. Use of smokeless tobacco products is increasing in South Asia [5–7], a major source of immigration to Australia. Some Scandinavian and US studies suggest that smokeless tobacco products, such as snus and snuff, are
less harmful alternatives to smoking, but research evidence to support this contention remains inconclusive [6]. Many studies conducted in India, the UK and the USA indicate that STC causes cancer of the oral cavity [6,8–10], throat, head and neck [5,11]. It also increases the risk of pancreatic cancer, diabetes, metabolic disease and cardiovascular disease [6,9]. Additionally, STC is a risk factor for stroke, high cholesterol and adverse pregnancy outcomes [12–14]. STC is common among South Asian people, including women [13,15,16]. More than one-third of total tobacco consumption in South Asia is in the form of smokeless tobacco [13,15]. The World Health Organization estimates there are nearly 250 million adult smokeless tobacco users in its South-East Asia region (including 26 million in Bangladesh), representing 90% of global smokeless tobacco consumers [5,17–20].
Correspondence to Dr Abul Hasnat Milton, School of Medicine and Public Health, Faculty of Health and Medicine,The University of Newcastle, NSW 2308, Australia. Tel: +61 2 4042 0525; Fax: +61 2 4042 0044; E-mail: [email protected] Received 1 April 2013; accepted for publication 10 September 2013. © 2013 Australasian Professional Society on Alcohol and other Drugs
Smokeless tobacco consumption in Sydney
In some parts of South Asia, such as Bihar and Maharashtra in India, one in three people uses smokeless tobacco, making it more popular than smoking [5,21]. It has also been shown that chewing of betel quid containing tobacco is common among Bangladeshi, Indian and Pakistani immigrants in the UK [5,21–23]. In Bangladesh, India and Pakistan, traditional values and social norms do not favor smoking by the young or by women, but there is no such taboo against STC [5]. The prevalence of smoking among women (1.5%) is very low compared with men (44.7%), whereas STC is almost equally common among women (27.9%) and men (26.4%) in Bangladesh [17]. STC is related to traditional values, spirituality, beliefs, festivals, and rituals, such as marriage [5]. Its perceived medicinal value for curing toothache, headache and stomachache leads many adults to become users, and some parents even encourage their children to use smokeless tobacco [5]. The types of smokeless tobacco products in use vary by region: snus in Europe, gutka and zarda in Asia and toombak in Africa [5,15,21–23]. Generally, sun- or aircured smokeless tobacco can be used by itself in unprocessed, processed or manufactured form [7]. Smokeless tobacco is also consumed as a component of betel quid, which is a combination with lime, areca nut and other ingredients [19]. There are various forms of smokeless tobacco in South Asia, such as zarda, gutka, Paan masala, Paan parag, tobacco with lime (calcium oxide), tobacco with areca nut, tobacco tooth powder (gul) and dried tobacco leaves [5,13,15,22]. Even within regions, there are differences in types of product that make it difficult to assess the severity of risks they pose. There are a large number of South Asian migrants in Sydney, Australia, and many more will migrate there in future.We hypothesised that a substantial proportion of South Asian ethnic residents of Sydney consume smokeless tobacco products. The aim was to estimate the prevalence of STC in these populations and its association with sociodemographic variables. Methods Design We conducted a cross-sectional survey. Sampling The participants were Australian citizens with Indian, Bangladeshi or Pakistani ethnic background living in the Sydney metropolitan area. We gained the cooperation of the Bangladesh Association of New South Wales, United Indian Associations and Pakistan Association of Australia in order to develop a sampling frame. We
87
initially communicated with the office bearers of these community organisations and explained the objectives and proposed methods of the study to them. They provided lists of eligible and easily identified members, from which we randomly selected samples.The number selected from each ethnic group was based on probability proportionate to size. A sample of 400 participants is sufficient to estimate a 50% prevalence of STC with 95% confidence interval of width ± 5%. In the absence of published prevalence estimates, we conservatively assumed a 50% prevalence of smokeless tobacco consumption. Assuming a response rate of 25%, we selected a total of 1600 of 6386 people from the three communities, i.e. 400/1605, 800/3198 and 400/1583 individuals with Bangladeshi, Indian and Pakistani background, respectively, from all eligible members. Measurement The questionnaire was designed to collect information on STC, product availability and knowledge and attitudes about STC, as well as sociodemographic information, such as age, gender, marital status, income, employment, education, country of birth and religion. ‘Ever consumption’ was defined as having ever consumed smokeless tobacco products in the respondent’s lifetime. ‘Consumed more than 100 times’ was defined as consumption of smokeless tobacco products at least 100 times in the respondent’s lifetime. ‘Current consumption’ was defined as having consumed smokeless tobacco products more than 100 times in the respondent’s lifetime and at least once-daily use in the preceding six months. Procedure In October 2010 we mailed a package containing an introductory letter, study information sheet and questionnaire, all in English, to all participants. Participants were asked to read the information sheet carefully. If the participant agreed to participate he or she completed the questionnaire and returned it in a postagepaid return envelope. Two hundred and seventy-two (17%) respondents completed and returned their questionnaire within three weeks. After four weeks, each non-respondent was sent a reminder by mail. The first author attended community meetings and made formal announcements about the project, inviting members to participate. In the following three weeks another 147 sample members (9%) completed and returned questionnaires. Ethical approval The University of Newcastle’s Human Research Ethics Committee approved the study (H-2011-0131). © 2013 Australasian Professional Society on Alcohol and other Drugs
88
M. S. Hossain et al.
Statistical analyses Independent-sample t-tests and one-way anova were used to estimate P values for differences in STC by age and gender. Categorical variables were reported as proportions, while continuous variables were summarised with means and standard deviations when distributions were approximately normal. Prevalence of STC was estimated as a proportion, and χ2-tests and t-tests were used to compare the demographic characteristics of current consumers, more-than-100-times consumers and ever consumers. Associations between STC and the exposures of interest were investigated using simple and multiple logistic regression. All the analyses were adjusted for the design effect using svy set in Stata 11 (StataCorp, College Station, TX, USA). To construct the final multivariate model, we adopted a backward elimination method. Any variable
that was significant at the 15% level in the univariate model was included in the base model. Association with the main exposure variable was estimated after adjusting for confounders and effect modifiers. The final model was based on the statistical significance of the covariates.We retained all the variables significant at the 5% level in the multivariate model. We excluded variables from the base model using backward elimination based on their P value, starting with the variable with the highest P value greater than 0.05.
Results Characteristics of the study participants The demographic characteristics of the study participants are presented in Table 1. A total of 419 individuals participated (response rate 26%), including 274
Table 1. Demographic characteristics of the study participants Country of birth
Variable Age (years) Mean Standard deviation Gender, n (%) Male Female Education, n (%) Postgraduate Undergraduate Non-tertiary (0 to12 years) Missing Religion, n (%) Muslim Hindu Others Missing Income per weekb, n (%) A$1000 Missing Employment, n (%) Business Full-time (>35 h) Part-time Looking for a job Missing Marital status, n (%) Married Unmarried Others
Bangladesh n = 139
India n = 150
Pakistan n = 130
37.4 8.91
39.1 5.92
38.3 5.30
90 (64.8) 49 (35.3)
87 (58.0) 63 (42.0)
97 (74.6) 33 (25.4)
0.014
274 (65.4) 145 (34.6)
54 (38.8) 64 (46.1) 21 (15.1) 0 (0.0)
53 (35.3) 41 (27.3) 48 (32.0) 8 (5.41)
46 (35.4) 36 (27.7) 32 (24.6) 16 (12.3)
0.002
153 (35.5) 141 (33.7) 101 (24.1) 24 (5.70)
91 (65.5) 41 (29.5) 6 (4.30) 1 (0.70)
6 (4.00) 124 (82.7) 13 (8.70) 7 (4.60)
125 (96.2) 0 (0) 2 (1.50) 3 (2.30)
100 times Current consumption n = 294 P value n = 199 P value n = 48 P value 294/408 (72.1) (67.4–76.4)
199/302 (65.9) (60.1–71.1)
48/281 (17.1) (12.9–22.0)
54/112 (48.2) 188/233 (80.7) 52/63 (82.5)
$AUD1000 $AUD500 to 1000 35 h) Part-time Looking for a job Marital status Unmarried Married Others
Ever consumption n = 294
Consumed >100 times n = 199
1 2.73 (1.70–4.31) 3.32 (2.71–3.92) 0.013
1 0.62 (0.12–4.41) 0.42 (0.13–1.82) 0.02
1 0.51 (0.13–2.11) 2.14 (0.43–10.5) 0.18
1 2.13 (1.51–3.13)
1 1.91 (1.04–3.81)
1 1.51 (0.83–2.82)
1 0.62 (0.22–1.80) 0.70 (0.23–2.04) 0.78
1 1.34 (0.21–10.6) 0.83 (0.23–3.14) 0.60
1 1.74 (0.52–5.91) 2.9 (0.24–41.7) 0.38
1 1.24 (0.13–19.4) 0.84 (0.13–6.64)
1 0.91 (0.23–3.11) 1.62 (0.33–9.01)
1 5.72 (2.30–14.52) 3.14 (1.51–6.50)
1 0.71 (0.14–92.2) 1.53 (0.12–184.1)
1 2.20 (0.14–46.2) 1.31 (0.12−16.2)
1 0.71 (0.32–1.9) 1.62 (0.14–19.1)
1 0.98 (0.23–4.70) 3.96 (0.14–244.1)
1 0.41 (0.21–1.02) 3.9 (2.34–6736344)
1 1.44 (0.31–6.42) 1.13 (0.14–2198.9)
1 1.20 (1.12–1.32) 0.41 (0.13−0.82) 1.14 (0.13−80.5)
1 0.71 (0.41−1.24) 0.32 (0.12−10.4) 0.71 (0.21−2.23)
1 0.61 (0.32–1.13) 6.74 (0.14–464.1) 0.63 (0.13−710.1)
1 4.32 (0.14−151.7) 1.12 (0.43−3.5)
1 9.93 (0.14−15 505.5) 7.94 (0.13−147 744.7)
Current consumption n = 48
Not applicableb Not applicable Not applicable
a Adjusted for all variables shown in the table. bMarital status was excluded from the multivariate model because of its nonsignificant association with current consumption.
Australian research conducted in 2004 reported that 94% of South Asian grocery shops in Sydney sell smokeless tobacco products, despite their sale being banned in Australia under the section 65C(7) of the Trade Practices Act 1974 [34]. In the first author’s experience of visiting shops in south-western Sydney, Paan masala, Paan parag and Baba zarda were visible on the shelves, while RMD gutka, Hakimpuri zarda and Raja khaini were hidden and had to be asked for. When asked if they knew that the sale of these products is illegal in Australia, most shopkeepers replied ‘yes’, but indicated that food inspectors and other authorities never asked about or commented on the matter. The findings underscore the need for restrictions on the availability of these products, firstly via enforcement
of existing legislation. It also highlights the need for education in South Asian ethnic groups in Australia on the health hazards of STC and for effective STC cessation programs [16,35]. In the short term there may be value in providing a low-cost intervention, such as feedback on the survey results, with leaflets informing respondents about the dangers of smokeless tobacco with advice to quit and access to cessation support services. Funding This research was conducted using a Research Training Scheme grant from the University of Newcastle, New South Wales, Australia. © 2013 Australasian Professional Society on Alcohol and other Drugs
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Acknowledgement The study would not have been possible without the cooperation of the office bearers of the Bangladesh Association of New South Wales, United Indian Associations and Pakistan Association of Australia in Sydney. Professor Kypros Kypri’s involvement was supported by a National Health and Medical Research Council research fellowship.
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