|Year : 2016 | Volume
| Issue : 2 | Page : 123-132
Social impacts on adult use of tobacco: findings from the International Tobacco Control Project India, Wave 1 Survey
Cecily S Ray1, MS Pednekar1, PC Gupta1, M Bansal-Travers2, ACK Quah3, GT Fong4
1 Healis Sekhsaria Institute for Public Health, Navi Mumbai, India
2 Department of Health Behavior, Roswell Park Cancer Institute, Buffalo, New York, United States of America
3 Department of Psychology, University of Waterloo, Waterloo, Ontario, Canada
4 Department of Psychology, University of Waterloo, Waterloo; Ontario Institute for Cancer Research, Toronto, Ontario, Canada
|Date of Web Publication||16-May-2017|
Cecily S Ray
Healis Sekhsaria Institute for Public Health, 501 Technocity, Plot X-4/5 TTC Industrial Area, Mahape, Navi Mumbai 400701
Background: Social impacts on tobacco use have been reported but not well quantified. This study investigated how strongly the use of smoked and smokeless tobacco may be influenced by other users who are close to the respondents.
Methods: The International Tobacco Control Project (TCP), India, used stratified multistage cluster sampling to survey individuals aged ≥15 years in four areas of India about their tobacco use and that of their close associates. The present study used logistic regression to calculate odds ratios (ORs) for tobacco use for each type of close associate.
Results: Among the 9780 respondents, tobacco use was significantly associated with their close associates’ (father’s, mother’s, friends’, spouse’s) tobacco use in the same form. After adjusting for confounding variables, women smokers were nine times more likely to have a mother who ever smoked (OR: 9.0; 95% confidence interval [CI]: 3.3–24.7) and men smokers five times more likely (OR: 5.4; 95% CI: 2.1–14.1) than non-smokers. Men smokers were seven times more likely to have close friends who smoked (OR: 7.2; 95% CI: 5.6–9.3). Users of smokeless tobacco (SLT) were five times more likely to have friends who used SLT (OR: 5.3; 95% CI: 4.4–6.3 [men]; OR: 5.0; 95% CI: 4.3–5.9 [women]) and four times more likely to have a spouse who used SLT (OR: 4.1; 95% CI: 3.0–5.8 [men]; OR: 4.3; 95% CI: 3.6–5.3 [women]), than non-users. The ORs for the association of the individuals’ tobacco use, whether smoked or smokeless, increased with the number of close friends using it in the same form.
Conclusion: The influence of family members and friends on tobacco use needs to be appropriately addressed in tobacco-control interventions.
Keywords: India, smokeless tobacco, smoking, social environment, tobacco, tobacco use.
|How to cite this article:|
Ray CS, Pednekar M S, Gupta P C, Bansal-Travers M, Quah A, Fong G T. Social impacts on adult use of tobacco: findings from the International Tobacco Control Project India, Wave 1 Survey. WHO South-East Asia J Public Health 2016;5:123-32
|How to cite this URL:|
Ray CS, Pednekar M S, Gupta P C, Bansal-Travers M, Quah A, Fong G T. Social impacts on adult use of tobacco: findings from the International Tobacco Control Project India, Wave 1 Survey. WHO South-East Asia J Public Health [serial online] 2016 [cited 2019 May 25];5:123-32. Available from: http://www.who-seajph.org/text.asp?2016/5/2/123/206249
| Background|| |
Tobacco use is a recognized public health problem worldwide and in India. It is implicated in cancer, cardiovascular disease, stroke, chronic lung diseases, adverse reproductive effects and higher mortality, with half of users dying prematurely. Therefore, it is important to understand the factors influencing individuals’ use of tobacco. In India, the prevalence of smoking is 14.0% overall (24.3% of men; 2.9% of women) and 25.9% use smokeless tobacco (SLT; 32.9% of men; 18.4% of women), as shown by the Global Adult Tobacco Survey. Tobacco use in India is higher in rural areas compared to urban areas, increases with age, and decreases with education as well as income.
It is important to understand the social context of tobacco use, to develop interventions promoting its cessation., Community surveys and interventions in India have shown that tobacco use is often learnt from parents, other elders and peers., Studies at workplaces and in educational institutions have reported similar findings.,,,
The rationale for the present study was that the pattern of impact of close social contacts using tobacco on individuals’ tobacco use has not yet been well quantified or studied by sex in India and that this information might be useful when designing effective interventions to control tobacco use. It was expected that the pattern of social impact on women’s use of tobacco, which is mainly SLT, would differ from that for men. The purpose of this study was to quantify the associations of tobacco use with its use by close social contacts, according to sex, in a large general population across different states of India.
| Methods|| |
The International Tobacco Control Policy Evaluation Project (the ITC Project), which in India is called the Tobacco Control Project (TCP), to avoid associations with the India Tobacco Company, conducted its baseline survey between August 2010 and December 2011. This provided an opportunity to study how strongly tobacco use (in smoked and smokeless forms) and specific product choices may be influenced by other users in the close social context. All study materials and procedures used in the TCP India Survey were reviewed and cleared for ethical issues by the Office of Research Ethics at the University of Waterloo, Canada, and by the Institutional Review Board at the Healis-Sekhsaria Institute for Public Health, Navi Mumbai, India. All participants gave informed consent and gave their consent for the publication of this study. Most participants signed the consent form, but many villagers were reluctant to sign it, owing to a misconception that signing any consent would force them to give up their land.
Sampling method and data collection
A stratified, multistage cluster sampling design was used to collect samples of adults (defined as persons aged 15 years and older), who included users of smoked tobacco, users of smokeless tobacco and non-users. Four major cities of four states (Mumbai, Maharashtra; Indore, Madhya Pradesh; Patna, Bihar; Kolkata, West Bengal), and rural areas within 50 km from city centres, were chosen for sampling.,
In each city, 10 wards were selected with probability proportional to their size. Within each ward, 10 census enumeration blocks (CEBs) were randomly selected. Selected CEBs were completely mapped within the defined geographic boundary and households in them were approached in random order for individual interviews. The intention was to include the maximum number of enumerated households in the first CEB and then proceed to the next, and so on, until the desired sample size of 150 households in the given ward was reached.
In each chosen rural district, two or three subdistricts were selected purposively, from which four villages with at least 1000 households were selected from a list of all villages in the selected subdistricts, using probability proportional to size. Using a map of each selected village, dwellings were sampled randomly (preferred) or systematically, enumerating 125 households in each village.
Up to four tobacco-using members were interviewed in each enumerated household and if there were more than four users, then four were selected with the role of a die. One adult non-user was selected from every third household containing at least one adult non-user of tobacco.
The sampling procedure aimed to recruit at least 2000 adult tobacco users and 600 non-users from approximately 1500 urban and 500 rural households in each state, which finally amounted to a total of 9699 households from the four states. Eligible persons included those living in households and belonging to one of four categories: smokers only, users of smokeless tobacco only, users of both smoked tobacco and smokeless tobacco, and non-users; for the present study, users of both smoked and smokeless forms of tobacco were excluded from the data analyses.
Trained interviewers used structured questionnaires to collect information in face-to face interviews with each respondent, in Hindi, Marathi, Bengali or English. As per the protocol, an information letter was provided and consent obtained from each participant.
Current use of any tobacco by respondents was defined as at least one use in the past 30 days by self-report. Tobacco users were categorized according to the form of tobacco they used: smoked, smokeless or mixed use (smoked and smokeless). For this study, all 805 mixed users from the original sample were excluded, in order to study the relationship between respondents’ smoking or SLT use with a similar form of tobacco use by close associates. The concept “close associate” in this paper includes father, mother, spouse and the five closest friends. Respondents were asked about current smoking and SLT use by their spouse (if married) and five closest friends, as well as about “ever” smoking and “ever” use of SLT by each parent (a parent could have died or quit tobacco use before the survey).
Smoked tobacco products included cigarettes, bidis (tobacco flakes wrapped in a tendu or temburni leaf), pipes, including the hookah (water pipe), other pipes (including the hookli and others), chuttas, cigars and other products., SLT products included: (i) those for chewing or holding in the mouth, e.g. plain chewing tobacco, generally sold loose; zarda, which is scented, branded chewing tobacco; khaini, consisting of finely cut tobacco mixed with slaked lime, either by the user or in packaged form, which is placed between the lips and gums; (ii) areca nut and tobacco mixtures for chewing: gutka, of which there are many brands sold all over India and that contains crushed areca nut with tobacco and slaked lime; betel quid, which is areca nut, tobacco, slaked lime and condiments, wrapped in a fresh betel leaf, prepared by vendors or at home; (iii) products commonly used for application to teeth and gums and as dentifrice, such as dry snuff (also called tapkir), gudhaku (a paste of tobacco and unrefined sugar, mainly used in West Bengal and Bihar), pyrolized products (gul and mishri, the latter being mostly used in Maharashtra) and lal dantmanjan (red toothpowder). Lal dantmanjan, of which there are several brands, although not claiming to contain tobacco, nor legally permitted to, has been found in some analyses to contain nicotine.,,
Binary logistic regression was used to calculate separate odds ratios (ORs) for (i) current exclusive smoking of tobacco and (ii) current exclusive SLT use and its use by close associates, using the Statistical Package for Social Studies (SPSS) Licensed Version 20. All ORs were adjusted for age (in three age groups: 15–39 years; 40–54 years and 55+ years), residence (urban or rural), state, and three levels of monthly household income (low: <?5000; moderate: ?5001–15 000; high: >?15 001). ORs for smoking and for SLT use were also separately calculated for the number of closest friends who used tobacco of the same type (smoked or smokeless). ORs were also calculated for any one, any two, any three and any four types of close associates who also smoked or used SLT. The chi-squared test for linear trend was performed using Epi Info Version 7. Sampling weights were applied to the data for all logistic regression calculations, to ensure better representativeness of the data.
| Results|| |
The sample consisted of 9780 respondents aged 15 years and above, with 5536 men (56.6%), as shown in [Table 1] . Among all respondents, 7015 (71.7%) were married and 7140 (73.0%) were from urban areas. A total of 1255 were exclusive tobacco smokers (of which 97% were men), while 5991 exclusively used SLT and 2534 were non-users of tobacco. Tobacco users were more concentrated in higher age groups compared to non-users. Higher proportions of tobacco smokers were rural, married and older compared to SLT users and non-users. West Bengal had the highest proportion of tobacco smokers; Maharashtra and Bihar had higher proportions of SLT users compared to the other states.
|Table 1: Sample characteristics by tobacco-use status in the International Tobacco Control Project India, Wave 1 Survey in 2010–2011 (n = 9780: 4244 women; 5536 men)|
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[Table 2] and [Table 3] show crude and adjusted ORs for use of smoked or smokeless tobacco, according to their use by close associates. Almost all of the adjusted ORs for tobacco users with close associates who used tobacco in the same form were elevated, and most were highly significant.
|Table 2: Odds ratios of association between tobacco use (exclusive smoking) by respondent and use by close associates, among men and women in the International Tobacco Control Project India, Wave 1 Survey in 2010–2011a|
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|Table 3: Odds ratios of association between smokeless tobacco (SLT) use by respondent and use by close associates, among men and women in the International Tobacco Control Project India, Wave 1 Survey in 2010–2011a|
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[Table 2] shows the results for smoking. The adjusted ORs for association with smoking by either parent were especially strong for women smokers (OR=7.3 and OR = 9.3 for father and mother who ever smoked, respectively), while for men, having close friends who smoked showed the strongest (OR=7.2) association. Product-wise, for men, the highest associations with close associates were for the combination of cigarettes and bidis, while for women, they were highest for exclusive bidi smoking. Since there were only two women who smoked cigarettes exclusively and only three women who smoked both cigarettes and bidis, these categories of women smokers were excluded from the table, as ORs could not be obtained. Further, since fewer than five married respondents reported that their spouse smoked, among both men smokers and women smokers, ORs for smoking by the spouse could not be calculated. This was partly due to poor response to this question.
[Table 3] shows the results for SLT use. The association of SLT use by parents with individual SLT use appeared strong for both men and women. This was significantly higher for mothers and daughters (OR: 4.0), than for mothers and sons (OR: 2.1). For women, the ORs for father’s ever use of SLT, were highest for use of khaini, gul and snuff and close to 3; again for women, for mother’s ever SLT use, ORs ranged from 2.5 to 5.4 for all SLT products. For men, ORs for use of specific SLT products for father’s ever SLT use were highest for gul, gudhaku and “other SLT”, but ORs for mother’s ever SLT use were highest for lal dantmanjan and gudhaku.
The association of SLT use with having any close friends who also used SLT was five-fold higher compared to non-tobacco users, for both men and women (see [Table 3]). For men who used gutka, khaini, plain chewing tobacco or zarda, the ORs for close friends’ SLT use were significantly higher than those for father’s or mother’s SLT use (no overlap of confidence intervals). For women, the same was true only for gutka. The highest OR for betel quid use was for women whose close friends used SLT.
Among SLT users, the high response rate for spouse use of SLT provided more than adequate numbers for OR calculation. ORs for SLT users whose spouse used SLT were generally intermediate between those for parents and friends using SLT (see [Table 3]). Women’s use of SLT was strongly associated with SLT use by their spouse, especially gutka, khaini, plain chewing tobacco, zarda, mishri and snuff. For men, lal dantmanjan use was highly associated with their spouse’s SLT use, as well as their mother’s SLT use. ORs for use of products applied to teeth and gums and used as dentifrice were elevated for all close associates using SLT, but tended to be highest for spouse’s SLT use, for both men and women.
[Figure 1] shows the association of tobacco use with the number of close friends using the same form of tobacco. The ORs increased rapidly with increasing numbers of friends using tobacco in the same form, for both men and women. Chi-squared values for linear trend were highly significant (P < 0.0001).
|Figure 1: Tobacco use and close friends using tobacco: odds ratios (OR, adjusted for age group, urban/rural residence, state and income) for respondents smoking tobacco and using smokeless tobacco (SLT) for the number of friends (among the five closest) using the same tobacco type as the respondents, by sex|
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[Figure 2] shows that the ORs for SLT use rose with increasing numbers of associates who used SLT (any one, any two, any three or all four among father, mother, close friends and spouse). The trend was highly significant (P < 0.0001).
|Figure 2: Use of smokeless tobacco (SLT) and number of close associates using SLT: odds ratios (OR, adjusted for age group, urban/rural residence, state and income) for exclusive respondent SLT use for close associates (father, mother, spouse, any close friend) using SLT, by sex|
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| Discussion|| |
This study shows that the use of tobacco by close social contacts is very likely to influence, i.e. impact or reinforce, tobacco use among adults in India. Friends appear to strongly influence both men and women to use SLT. For smoking, friends appear to strongly influence men more than parents, while the reverse is true for women. The influence of mothers on daughters to use tobacco appears especially strong. Among married SLT users, the spouse is also likely to be a user and, in particular, wives seem to influence their husbands to use tobacco-based dentifrices, like lal dantmanjan or mishri. Individuals are increasingly likely to use tobacco in any form, as more of their close social contacts use it. The implications of this survey, conducted in both urban and rural areas of four states, may well be generalizable to the whole of India.
Considering that the sampling criteria for this study (persons aged 15 years and above) included a large part of the adolescent age group, it seems relevant that a previous study of adolescents in Noida city, Uttar Pradesh found a similar order of association: among 4786 students aged 11–19 years in classes VII to XII, tobacco users were more than eight times more likely to have friends or classmates who also used tobacco (OR: 8.6; 95% confidence interval [CI]: 6.3–12.0), seven times more likely to have a mother who used it (OR: 7.2; 95% CI: 4.2–12.1) and three times more likely to have a father who used tobacco (OR: 3.0; 95% CI: 2.2–4.1).
Four earlier studies from India quantified associations of tobacco use by individuals with that by friends or peers. In a study among 1587 male students (aged 16–23 years) at 11 colleges in southern Karnataka, smokers were five times more likely to have friends who smoked compared to non-smokers. A community study among 500 youth aged 15–24 years in urban and rural Chandigarh found that youth were much more likely to smoke if their friends smoked (OR: 40; 95% CI: 11.4–142.8). In a study of use of smokeless tobacco among 336 office workers in Mumbai, 61% of lower-level workers and 83% of male clerks reported that peer pressure was an influence on their use of SLT, especially gutka? In a small intervention study of 104 factory workers in Ratnagiri district of Maharashtra, peer influence for tobacco use on and off the job was found to be important (but not quantified), mainly for SLT in that population. In a qualitative study using focus groups of teachers in India, in the two states of Maharashtra and Bihar, on patterns of tobacco use and social norms, a response from Bihar indicated that tobacco use is culturally ingrained, owing to tradition, is inherited from fathers and forefathers and is considered a right.
Studies available from other countries also report social influence or impact on tobacco use by friends and/or parents.,,, For example, in a study in Italy on 7469 persons aged 15 years and above, 61% reported smoking as a result of the influence of friends; men were more likely to report the influence of friends, but women more frequently reported the influence of parents or their partner.
The present study shows that in India, mothers’ influence on women’s smoking is especially strong. Although not studied previously in India, a similar phenomenon has been reported in a 20-year literature review of 51 studies published during 1989–2009 on mothers’ smoking and adolescent smoking, which included studies from North America, Europe, Oceania and Asia. Forty-three studies (84.3%) found a positive association between the mothers’ smoking and that of their adolescent offspring; among these, 21 found the mothers’ tobacco smoking was more strongly associated with girls’ own smoking than that of boys.
The phenomenon of parental and peer influence on smoking has sometimes been explained with the help of the social learning theory from psychology, according to which individuals imitate behaviours they observe being modelled by individuals with whom they identify closely, such as parents, elder siblings and peers/friends, teachers and the media., While initiation to tobacco use may occur in adolescence or earlier, and may be partly influenced by parents and friends, role modelling by these significant others may remain important for continuation of tobacco use into adulthood, aided by addiction to nicotine.
The present study also showed that SLT use is highly associated with spouses’ use of SLT, and these associations were intermediate in value between those for parents and close friends. In particular, use of SLT products as a dentifrice by men appears strongly associated with the use of these products by their wives.
The significance of having friends who smoke may extend to quitting intention and behaviour. In a qualitative study among 60 disadvantaged women users of SLT in Delhi, participants expressed that seeing others around them chewing tobacco would pose a challenge to quitting. On the other hand, the ITC Four Country Survey found that smokers who lost touch with smoking friends between two waves of the survey were significantly more likely to have attempted to quit (OR: 1.5; P < 0.0001) and to have quit successfully (OR: 1.6; P < 0.01) than those who did not lose any smoking friends during the same period.
The present results converge with the social impact theory, in which the impact of other people on the individual (in terms of behaviour, beliefs, values and feelings) is a multiplicative function of the number of other people involved. Also according to that theory, the importance of those people to the individual increases their impact and so does their immediacy, i.e. in space or time. For adults, a spouse and close friends would have considerable influence, perhaps more than parents, as shown in the present study.
A limitation of the study data was that substantial proportions of married respondents did not want to address the possibility of tobacco smoking by their spouse: 16.9% of married men (169 out of 999) who said they were smokers and 66.7% of married women (16 out of 24) who identified themselves as smokers did not respond to the question on spouse smoking; also, 11.7% (52/445) of men non-users and 34.7% (425/1226) of women non-users did not answer the question on spouse smoking. The low numbers of men as well as of women smokers responding on spousal smoking was partly due to the paucity of women smokers, since the prevalence of women smokers is low in India, and partly due to considerable non-response on tobacco smoking by the spouse. By contrast, non-response among SLT users on SLT use by their spouse was only 2% among men and 14% among women; in addition, as many as 26.4% of married men who used SLT and 64.5% of married women who used SLT said their spouse also used SLT (data not shown). Also, since many women SLT users (13.7% [235/1715]) and non-users (16.2% [199/1226]) were unaware of, or unwilling to discuss, their husband’s use of SLT, results on husbands’ use of SLT might be somewhat biased. Only 2.0% (51/2606) of men did not answer about their wife’s use of SLT. Lack of knowledge or reluctance to answer questions about parental or friends’ tobacco use in any form varied only from 0% to 4.1% (104/2552; the latter for women answering whether their father ever used SLT). Investigation of the reasons for non-disclosures on spousal tobacco use could shed light on underlying views and feelings on the acceptability of tobacco use.
A second limitation was that specific products used by close associates were not recorded. A third limitation was that the study did not look at the sex-wise direction of friends’ influence.
The findings of this study suggest that tobacco-control interventions might be more effective if they distinctly addressed social influences on tobacco use generally and on specific products. Better enforcement of laws against tobacco in dentifrices could also greatly help to reduce their use, since these products are used by whole families. The influence of any form of advertising (including point-of-sale or surrogate advertising) on an individual is potentially amplified by the influence of that person’s tobacco use on their close social contacts. Thus, enforcement of rules banning tobacco advertising can potentially prevent or reduce tobacco use even by those not exposed to the advertisements. Future research could design and analyse interventions that address social networks to encourage cessation of tobacco use.
| Conclusion|| |
In India, adult use of tobacco is strongly associated with having one or more close social contacts who use tobacco in the same form. The influence of family and friends on tobacco use needs to be addressed in tobacco-control interventions, to reduce its social acceptability.
| Acknowledgements|| |
We thank the project managers at the University of Waterloo, Canada and those at Healis Sekhsaria Institute for Public Health in India, the state collaborators and all the interviewers and respondents. We also thank Mr Sameer N Narake, Healis, for technical support for data analysis and checking of results and Ms Jooi Vasa, Healis, for editorial comments.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3]