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ORIGINAL ARTICLE
Year : 2017  |  Volume : 61  |  Issue : 5  |  Page : 40-46  

Tobacco use among thai students: Results from the 2015 global youth tobacco survey


1 Director of Bureau of Tobacco Control, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
2 Deputy Director of Bureau of Tobacco Control, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
3 Data Assistant, Bureau of Tobacco Control, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
4 Director, Tobacco Control Research and Knowledge Management Centre, Mahidol University, Salaya, Thailand
5 Surveillance Management Associate, Noncommunicable Diseases and Environmental Health Department, WHO South-East Asia Regional Office, New Delhi, India
6 Medical Officer, Noncommunicable Diseases, WHO Country Office, Nonthaburi, Thailand

Date of Web Publication15-Sep-2017

Correspondence Address:
Renu Garg
Medical Officer, Noncommunicable Disease, WHO Country Office for Thailand, Tiwanon Road, Nonthaburi
Thailand
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijph.IJPH_234_17

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   Abstract 

Background: Tobacco use often starts in adolescence and is a leading cause of premature mortality. Two previous rounds of the global youth tobacco survey (GYTS) found that a significant proportion of Thai youth currently smoke. Objectives: We conducted the third round of GYTS in Thailand in 2015 to monitor trends in tobacco use. Methods: We selected 31 public and private secondary schools using random sampling based on probability proportional to school enrolment. In each school, we selected 1–3 classes (Grades 7–9) by random sampling. All students in these classes from 30 schools (one school declined) completed a self-administered standard questionnaire in the Thai language. The association between tobacco use and independent variables was examined using univariate and multivariable logistic regression analysis. Results: Of 1876 students, 1721 were aged 13–15 years. Overall, 15% of students currently used tobacco; boys 21.8% and girls 8.1%. The prevalence of current cigarette smoking was 11.3%; 3.3% students currently used electronic cigarettes. Exposure to secondhand smoke (SHS) at home, school, and in enclosed public places was reported by 33.8%, 47.9%, and 38.6%, respectively. Among current smokers, 44% were not stopped from purchasing cigarettes despite being underage. Higher tobacco use was associated with being older, male, exposed to SHS, in possession of an object with a tobacco logo, and being offered a free tobacco product by a tobacco company. Conclusion: Tobacco and cigarette use among Thai students remains high. Underage current smokers have easy access to cigarettes. Urgent steps are needed to curb the access of youth to tobacco.

Keywords: Cigarette smoking, electronic cigarettes, global youth tobacco survey, prevalence, shisha, Thailand, tobacco, youth


How to cite this article:
Chotbenjamaporn P, Haruhansapong V, Jumriangrit P, Pitayarangsarit S, Agarwal N, Garg R. Tobacco use among thai students: Results from the 2015 global youth tobacco survey. Indian J Public Health 2017;61, Suppl S1:40-6

How to cite this URL:
Chotbenjamaporn P, Haruhansapong V, Jumriangrit P, Pitayarangsarit S, Agarwal N, Garg R. Tobacco use among thai students: Results from the 2015 global youth tobacco survey. Indian J Public Health [serial online] 2017 [cited 2019 Mar 26];61, Suppl S1:40-6. Available from: http://www.ijph.in/text.asp?2017/61/5/40/214903


   Introduction Top


Tobacco use is a leading cause of preventable morbidity and premature mortality worldwide.[1],[2] The World Health Organization estimates that >6 million people die each year from smoking or exposure to secondhand smoke (SHS).[3] Tobacco use remains a serious public health and development issue in Thailand. According to the Global Burden of Disease study, tobacco use accounts for >10% of the disease burden in Thailand.[4] In 2013, the total economic burden from smoking was 75 billion Thai Baht, amounting to 18.2% of total health expenditure and 0.8% of the national gross domestic product.[5]

Adolescence is a vulnerable period for initiation of smoking – most smokers begin using tobacco before the age of 18 years.[6] Therefore, tobacco companies spend billions to market their products to the young. Nearly, four out of five Thai adults start smoking during their teen years.[7] The overall trend in cigarette use among adults has decreased fairly steadily since 1991 and has plateaued in recent years.[8] However, the trend in cigarette use among youth has not decreased in the past decade. In the previous two rounds of the Global youth tobacco survey (GYTS) in 2005 and 2009, the prevalence of current cigarette use remained high at about 11%.[9] In another nationally representative population-based survey among adolescents, tobacco use increased from 12% to 18.3% between January 2005 and March 2008.[10] In addition, the National Statistical Office survey in 2011 found that the starting age of recent smokers was as low as 6 years of age.[11]

Reducing tobacco use among youth is a key to ending the tobacco epidemic. Trends in the prevalence of tobacco use among youth indicate trends in new smokers – this is an important indicator that needs to be systematically monitored. GYTS, a systematic youth tobacco survey, is a globally standardized, robust tool for monitoring the prevalence of tobacco use as well as for examining tobacco control measures.[12] Data from the GYTS can provide the evidence base needed for policy formulation and implementation to better control tobacco use among youth. We conducted the third round of GYTS in Thailand, to estimate the prevalence of tobacco use, exposure to SHS, access to tobacco products, and other important indicators among youth.


   Materials and Methods Top


We conducted the third round of GYTS from November to December 2015 using the standard methodology.[12] We carried out a cross-sectional survey among students aged 13–15 years corresponding to Grades 7–9 in sampled public and private secondary schools from all over Thailand. We used a two-stage cluster sampling methodology to produce a representative sample of students. The sampling frame consisted of all public and private schools from all over Thailand with students in the age group of 13–15 years. A total of 11,503 schools were included in the sampling frame. In the first stage, we selected 31 schools using probability proportional based on the size of school enrollment. Schools having <40 students were excluded from the study. At the second stage, we randomly selected classes within each selected school. All students in the selected class were invited to participate in the survey irrespective of age. A total of 1876 eligible students in 65 classes completed the survey.

The standard core questionnaire (42 multiple-choice questions) with a set of optional questions (15 questions) was adapted to meet country needs and translated into the Thai language and back into English independently to check for accuracy. The questionnaire covered the following topics: tobacco use (smoked and/or smokeless); cessation; SHS; pro-and anti-tobacco media and advertising; access to and availability of tobacco products; and knowledge and attitudes regarding tobacco use. Questions on the use of e-cigarettes were included for the first time in this third round of GYTS.

Using standard definitions (Centers for Disease Control, GYTS questionnaire guide, version 1.0, 2012), “ever use” was defined as the use of tobacco even once in the lifetime. “Current use” was defined as the use of tobacco within 30 days of the survey. Tobacco use included smoking cigarettes, shisha and e-cigarettes, or use of smokeless tobacco, such as chewing shredded tobacco, inhaling through the nose, and chewing betel leaves with tobacco.

Data were analyzed using SUDAAN 9.0 (Research Triangle Institute, Research Triangle Park, North Carolina, USA), which computed standard errors of the prevalence estimates and produced 95% confidence intervals (CIs). A weighting factor was applied to each student record to account for nonresponse by school, class and student, and probability of selection at the school and class levels. Among 31 sampled schools, one school declined to participate. Therefore, the school response rate was 96.8%. The class response rate was 100% and the student response rate among 30 schools was 89%, nonresponse being due to the absence of some students on the day of the survey. Thus, the overall response rate was 86.1%.

To assess the association between tobacco smoking and selected variables, we carried out univariate and multivariable logistic regression analysis. Tobacco use was the dependent variable (dichotomous variable) in our model and we included a number of predictor variables: age, gender, parental tobacco use, exposure to SHS, possession of objects with tobacco logo, exposure to tobacco advertisement on internet and at point of sale, being approached by tobacco company representative, and exposure to anti-tobacco messages in the media. There was no significant multicollinearity observed among the predictor variables. The predictive power obtained from the Cox-Snell R2 for the dependent variable was computed using Taylor linearization methods assuming with replacement design. Although the R2 = 0.152 was comparatively lower than the desired level for behavioral studies like this one, our model was fitted to the data very well according to goodness-of-fit tests. Adjusted odds ratios (AOR) and 95% CIs were computed using SUDAAN. P < 0.05 was considered statistically significant.

The institute for the development of human research protection provided ethics approval for the GYTS. Anonymity, confidentiality, and willingness of the participants were ensured, and consent obtained from each participant and their parents.


   Results Top


Tobacco use and exposure to secondhand smoke

Of 1876 students who participated in the survey, 1721 were aged 13–15 years (51.2% boys and 48.2% girls). Overall, 15.0% (95% CIs: 11.2%–19.8%) of students were current tobacco users and 11.3% (95% CI: 8.2%–15.3%) currently smoked cigarettes [Table 1]. Smokeless tobacco was much less used than smoked tobacco (2.7% vs. 14.0%). Use of new tobacco products such as electronic cigarettes was reported for the first time. A total of 3.3% (95% CI: 2.2%–5.1%) of students currently used electronic cigarettes and 5.6% (95% CI: 3.7%–8.2%) were current shisha smokers. The use of all forms of tobacco was three times more common among boys than girls. In all, 7.4% (95% CI: 5.6%–9.7%) of never smokers mentioned that they may start using tobacco in the future.
Table 1: Prevalence of tobacco use and exposure to secondhand smoke among students aged 13-15 years, by gender, Global Youth Tobacco Survey, Thailand, 2015

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Exposure to SHS at home, school, and in enclosed public places was reported by 33.8% (95% CI: 29.6%–38.3%), 47.9% (95% CI: 41.9%–54.0%), and 38.6% (95% CI: 33.5%–44.0%) students, respectively. More than three-fourths of students (77.6%; 95% CI: 74.7%–80.4%) thought that SHS was harmful to them and a similar proportion of students (78.9%; 95% CI: 76.1%–81.4%) was in favor of banning smoking at outdoor public places.

Initiation of tobacco smoking, access, and purchasing pattern

The majority of ever smokers (39.6%; 95% CI: 33.1%–46.4%) initiated cigarette smoking between the age of 12 and 13 years [Table 2]. Over half the students smoked more than one cigarette a day. Girls smoked fewer cigarettes than boys. Two-thirds (67.4%; 95% CI: 58.5%–75.3%) of current smokers purchased cigarettes from stores, small groceries, stalls, flea markets, or convenience stores. Importantly, nearly half (44.0%; 95% CI: 31.7%–57.1%) of them faced no difficulty in buying cigarettes because they were underage. One in five current cigarette smokers purchased loose cigarettes as individual sticks and another 19% bought cigarettes in a divided packet [Table 2].
Table 2: Characteristics of cigarette smokers aged 13-15 years, Global Youth Tobacco Survey, Thailand, 2015

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Smoking cessation

Four out of five current smokers (79.4%; 95% CI: 70.0%–86.3%) had tried to quit smoking in the past 12 months. In addition, nearly three-fourths (72.2%; 95% CI: 59.8%–81.9%) wanted to stop smoking. However, only 29.3% (95% CI: 22.5%–37.2%) had received help or advice to stop smoking [Table 2].

Exposure to pro-tobacco advertising

Thai students are frequently exposed to pro-tobacco marketing from different channels [Table 3]. Nearly, three-fourths of students (72.6%; 95% CI: 69.0%–75.9%) had seen someone using tobacco on television, videos, or movies. About one-third of students (30.9%; 95% CI: 27.4%–34.6%) noticed tobacco advertisements at points of sale. Nearly, two out of five students (38.1%; 95% CI: 33.5%–42.8%) noticed advertisements of cigarettes or other tobacco products, and over one-fourth of students (27.0; 95% CI: 23.7%–30.6%) noticed electronic cigarette advertisements on the internet or other online media. In all, 10.5% (95% CI: 8.8%–12.4%) students owned something with a tobacco logo on it and 7.3% (95% CI: 5.3%–9.9%) were offered a free tobacco product from a tobacco company representative.
Table 3: Exposure to pro- and anti-tobacco advertising among students aged 13-15 years, by gender, Global Youth Tobacco Survey, Thailand, 2015

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Exposure to anti-tobacco messages

Three-fourths of the students (74.9%; 95% CI: 70.6%–78.7%) saw or heard anti-tobacco messages in the media such as television, radio, internet, billboards, posters, newspapers, magazines, or movies. The majority of the students mentioned that they were taught about the dangers of tobacco use in their school.

Knowledge and attitudes toward tobacco

The majority of students thought that other people's smoking was harmful to them and was in favor of a ban on smoking. However, in contrast, more than one-fourth (27.7%; 95% CI: 25.6%–29.9%) of the students felt that smoking tobacco helps people feel more comfortable at celebrations, parties, and social gatherings, and 16.6% (95% CI: 14.6%–18.9%) of students thought that it would be difficult to quit once someone started smoking tobacco [Table 2].

Factors associated with smoking

Tobacco use increased with age and almost was 3 times higher in boys than in girls [Table 4]. Students who were offered a free tobacco product by a company representative were significantly more likely to use tobacco than those who were not (54.5% vs. 11.5%; AOR = 5.0, 95% CI: 3.7–6.9). Other factors associated with higher odds of using tobacco were possessing an object with a tobacco logo on it and exposure to SHS. On the other hand, learning about the harms of tobacco use at school and exposure to anti-tobacco messages in the media protected youth from smoking.
Table 4: Factors associated with tobacco use by univariate and multivariable logistic regression analyses among students aged 13-15 years, Global Youth Tobacco Survey, Thailand, 2015

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   Discussion Top


We found that tobacco use remains high among Thai youth, with one out of six students currently using tobacco. As shown in previous surveys, boys were significantly more likely to use tobacco than girls. The overall prevalence of tobacco use and current cigarette smoking has not declined since the previous GYTS in 2009.[13] Newer products such as electronic cigarettes, which were assessed for the first time in this survey, are also being used by the youth. Cigarette smoking, the predominant form of tobacco use, has remained unchanged at 11% since the previous two rounds.[9],[13] Of concern is the fact that there was an increase in cigarette smoking among girls, from 3.8% in 2009 to 5.2% in this round.

Tobacco use is much higher in Thai schoolchildren compared to their peers in India, Myanmar, Nepal, and Sri Lanka.[14] Thailand has been an example of progressive tobacco control policies and legislations. Yet, cigarette smoking among Thai youth remains high and has not declined in the past decade. There may be several explanations for this. First, cigarettes, particularly “roll your own” cigarettes are inexpensive and affordable in Thailand. Moreover, cigarettes are sold as single sticks or divided packets, which makes it even more easy for students to purchase them. Sale of single cigarettes is a risk factor for smoking among youth. In Malaysia, more than half of the male students surveyed reported that they bought cigarettes as single sticks or in divided packets, and 82% of these students used their school pocket money to purchase cigarettes.[15] Tobacco use among the youth is price-sensitive. Nearly, 40% of students in our study bought single sticks or divided packets, indicating that the price of the cigarettes mattered to them. Second, cigarettes are easily available to the youth at various grocery stores and convenience stores where they are sold illegally to underage children. Despite laws that ban the sale of tobacco products to minors, 67.4% of current smokers could easily buy tobacco products, showing a continuing upward trend, from 38.1% in 2005 to 47.9% in 2009. The proportion of current smokers who were not prevented from buying cigarettes despite being underage also increased from the last two rounds of GYTS; 28.3% in 2005, 38.3% in 2009, and 44.0% in 2015. These data indicate weak enforcement of existing laws and are a major contributor to the continuing high rate of smoking among the youth. Finally, indirect tobacco advertisements and promotion by the tobacco industry are undermining tobacco control in Thailand. In our study, students who were offered a free product by a tobacco company representative were five times more likely to use tobacco than those who were not. Furthermore, students who owned an object with a tobacco logo were more likely to use tobacco. Furthermore, we found that a significant proportion of Thai students is being exposed to pro-smoking media campaigns and tobacco marketing as well as to “point-of-sale” advertisements. These data indicate an urgent need to “de-normalize” tobacco use in society.

The new Tobacco Product Control Act, which was recently passed on March 3, 2017, includes a number of provisions to address some of the above challenges that are undermining tobacco control in Thailand. These include increase in the minimum age of purchase of cigarettes from 18 to 20 years; ban on sale of single cigarettes or divided packets; provision for standard packaging; total ban on advertising, including total ban on display of tobacco product at point of sale; expansion of the scope of definition of tobacco to include e-cigarettes and water pipes; and stricter penalties for noncompliance with the law.

Our survey also shows a number of areas where progress has been made since the previous GYTS. There has been a significant increase in the proportion of children learning about the harms of tobacco use in school from 59.6% in 2009 to 76.2% in this survey. Furthermore, three-quarters of the students reported noticing anti-tobacco messages in the media. Our multivariable analysis shows that learning about dangers of tobacco in school and exposure to anti-tobacco measures in the media protected the youth from smoking. These positive changes may have resulted from the implementation of a number of school-based interventions and policies by the ministries of health and education, along with non-governmental organizations such as ASH Thailand and Thai Health. Furthermore, these agencies have been running hard-hitting anti-tobacco media campaigns. Another positive finding was that exposure to SHS at home or inside any enclosed public place dropped dramatically from 67.6% in 2009 to 38.6% in 2015. Exposure to tobacco smoke at any outdoor public place, which was reported for the first time in this survey, was also similarly low at 37.7%. These findings reflect the impact of the government's 2010 policy of a total ban on smoking in all public places (including a total ban in schools).

Study limitations and strengths

Our study should be interpreted in the light of at least two limitations. First, the survey questionnaire was self-administered; therefore, the results reflect self-reported data. It is possible that students may have under- or over-reported their behaviors or attitudes. Although we were not able to validate the responses during this survey, studies conducted elsewhere indicate good reliability of the methods.[16] Second, because GYTS is limited to youth attending school only, it may not be representative of all adolescents aged 13–15 years. However, as only a small proportion of Thai youth are out of school at this age, this may not affect the results significantly. Moreover, student response rates were very high, suggesting that bias attributable to absence or nonresponse would be minimal.

Despite these limitations, the survey provides valuable information on a wide range of potential determinants of cigarette smoking among Thai youth and is an important tool for identifying areas that need to be strengthened further. This is a nationally representative survey with a high student response rate that used a robust internationally standardized methodology. The questionnaire and methodology used in this survey were similar to those used in the previous rounds, allowing comparison of findings over time.


   Conclusion Top


The third round of Thailand's GYTS provides evidence of continuing high use of conventional tobacco products among Thai youth and the emerging use of electronic cigarettes among youth for the first time. With the recent passage of the landmark new Tobacco Product Control Act, it is an opportune time to step up actions to curb tobacco use among the youth. While the new legislation includes a number of measures to protect youth from smoking, it will be effective only if it is enforced strongly. It is critical to strengthen mechanisms of law enforcement in Bangkok as well as in the provinces, and closely monitor adherence to and compliance with the law. Stringent law enforcement together with improved tax measures and periodic monitoring using GYTS should go a long way in preventing smoking initiation by Thai youth – the key to stopping the tobacco epidemic.

Acknowledgments

We are grateful to the following individuals and institutions who participated in the survey: teachers and the Ministry of Education, including the Office of the Basic Education Commission, the Office of the Private Education Commission, and Office of the Higher Education Commission; Ministry of Interior (Department of Local Administration); and Bangkok Metropolitan Administration (Department of Education), field workers from the Department of Disease Control and other networks. We appreciate technical assistance team including Associate Professor Dr. Nithat Sirichotiratana, Associate Professor Dr. Aronrag Cooper Meeyai, and Assistant Professor Dr. Supawan Manosoontorn. We acknowledge the immense technical assistance for sampling, data entry, and data analyses by the USA Centers for Disease Control and Prevention (CDC), in particular, Dr. Krishna Palpudi and Ms. Linda Anton. Financial assistance for the study was provided by the WHO Country Office, Thailand.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
   References Top

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