Patterns and Correlates of Tobacco Use Among PLWH in Viet Nam: A Cross-Sectional Analysis

Abstract

Introduction

The use of multiple tobacco products may increase nicotine dependence and reduce success in quitting. In Viet Nam, the prevalence of dual cigarette and waterpipe use is high, yet the characteristics of dual users, particularly among people living with HIV (PLWH) in low-and-middle income countries (LMICs) are underexplored. This paper describes patterns and correlates of tobacco use among PLWH in Viet Nam.

Methods

This cross-sectional analysis utilized baseline survey data from a randomized controlled trial. Participants (n = 672) were ≥ 18 years old, current cigarette smokers, and receiving care at one of 13 HIV clinics in Ha Noi. Tobacco use pattern (cigarette-only vs dual waterpipe and cigarette use) was determined by self-reported use in the past 7 days. Sociodemographic characteristics, health status, household smoking rules, substance use, and perceived smoking risks were examined using bivariate analysis, with Wilcoxon’s rank sum test and Pearson’s Chi-sq tests used to assess statistical significance.

Results

Half of the sample (50.3%) reported dual waterpipe and cigarette use. Dual use was significantly associated with a lower level of education, lower annual income, and poorer health compared to cigarette-only smokers. Dual users were less likely to report a no-smoking household policy, and more likely to have a higher level of nicotine dependence. Participants from both user groups perceived waterpipe smoking as less harmful compared to cigarette smoking.

Conclusion

There is a high prevalence of dual tobacco use among PLWH in Viet Nam. Understanding the characteristics of dual users is critical for developing comprehensive tobacco control policies and cessation strategies tailored to this population in Viet Nam and other LMICs.

Keywords

HIV smoking tobacco use waterpipe smoking cigarette smoking health disparities Viet Nam low- and middle-income countries smoking cessation substance use behavior

Introduction

Multinational surveys show that smoking prevalence is significantly higher among people living with HIV (PLWH) compared with HIV-negative individuals across regions and country income.^1,2 Widespread access to antiretroviral therapy has significantly reduced HIV-related mortality.^3,4 Tobacco use threatens to undermine these gains, particularly in low- and middle-income countries (LMICs), where over 80% of people who use tobacco reside.^5,6 It is estimated that the life expectancy of PLWH who smoke is on average 8 years less than their nonsmoking counterparts.⁷

Cigarette smoking is the most common form of tobacco consumption.⁸ However, the use of alternative nicotine products, such as waterpipe (ie, hookah, narghile, shisha), is also prevalent in the Eastern Mediterranean and Southeast Asian regions.^9–13 Viet Nam has one of the highest smoking rates in the world. In 2020, the prevalence of combustible tobacco use among men was 41.1%.¹⁴ Waterpipe use is the second most common type of smoking nationally.^15,16 Dual use of cigarettes and waterpipe is also prevalent in Viet Nam.¹⁷ Among 1318 people enrolled in a tobacco cessation trial in Viet Nam, 37.1% reported dual use.¹⁸ Data from U.S. studies indicate a disproportionate prevalence of poly-tobacco use among PLWH compared with the broader population, but there is a lack of data on dual use among PLWH in LMICs, specifically on the combined use of both waterpipe and cigarettes.¹⁹

Growing evidence supports a positive association between waterpipe smoking and excess risk of non-communicable disease.²⁰ Dual use may further intensify nicotine dependence and reduce the likelihood of achieving smoking abstinence.²¹ However, the prevalence and added health risks associated with dual waterpipe and cigarette use, particularly among PLWH, is understudied. It is essential to identify factors associated with poly-tobacco use in vulnerable populations, such as PLWH, to effectively monitor trends and to guide tobacco policy and cessation services. This report describes and compares characteristics and correlates of cigarette-only use and dual use among a population of PLWH who were receiving care in HIV clinics in Viet Nam.

Methods

Study Design

We conducted a cross-sectional analysis of baseline survey data from 672 patients enrolled in a randomized controlled trial that compared the effectiveness of 3 tobacco use treatments among PLWH from November 2021 to September 2023 in Ha Noi, Viet Nam. Details about the trial have been previously published.²² The baseline survey was pilot tested with 16 patients (2.3% of the baseline sample). The trial was approved by the Institutional Review Boards of New York University, USA (approval no. i19-01783) and the Institute of Social and Medical Studies, Viet Nam (approval No: 00007993).

Participants and Recruitment

Eligible participants were ≥ 18 years old, used cigarettes daily, lived in Ha Noi, had daily access to a mobile telephone, and were receiving care in one of 13 HIV outpatient clinics (OPCs) in Ha Noi, Viet Nam. Participants were excluded if they were currently using tobacco cessation medication, were enrolled in a smoking cessation program (eg, National Quitline), reported a contraindication to using nicotine gum, or were pregnant or breastfeeding. Patients were initially screened for current cigarette use by an OPC nurse and referred to a Research Assistant for further eligibility screening. Those who met the eligibility criteria and provided written consent were enrolled, randomized and completed the baseline survey. Participants were consecutively enrolled across 13 OPCs to minimize selection bias.

Measures

Daily cigarette use was assessed with the question, “Do you currently smoke cigarettes every day, some days, or not at all?”²³ All cigarette users were asked if they used water pipe. Patients who indicated waterpipe use “some days” or “every day” were classified as dual users.

We examined sociodemographic characteristics (age, sex, educational attainment, annual household income, marital status), household smoking rules, self-reported overall health status,²⁴ depression (Centre for Epidemiology Scale for Depression (CESD-8),²⁵ nicotine dependence (Fagerström Test for Nicotine Dependence),²⁶ and substance use (Alcohol Use Disorders Identification Test - Consumption (AUDIT-C) to assess hazardous drinking and past 30 day use of marijuana, cocaine, heroin, amphetamines, glue, MDMA, and/or opium use, and current methadone treatment)²⁷ to describe the sample and explore as covariates. We assessed the perceived risk of using waterpipe vs cigarettes with the question, “Which is more harmful to your health, waterpipe or cigarettes?” with response options “Cigarettes”, “Waterpipes” or “Equally harmful”.²⁸ To analyze nicotine dependence among dual users, we separately calculated dependence scores for cigarettes and waterpipes and chose the higher of the two to represent overall nicotine dependence.²⁹

Statistical Analysis

Descriptive statistics were used to examine sociodemographic characteristics, health status, household smoking rules, nicotine dependence, substance use, and perceived smoking risks. Differences between cigarette-only and dual users were examined using bivariate analysis. Wilcoxon’s rank sum test for continuous variables and Pearson’s Chi-square test for categorical variables were used to assess statistical significance. To address missing data, 100 imputed datasets were generated by predictive mean matching, with results pooled using Rubin’s rules. The imputation step was done separately for cigarette-only and dual use groups.

Results

In the parent study, 1678 participants were examined for eligibility, 850 were confirmed eligible, and 672 were enrolled in the study after excluding 178 who did not meet the inclusion criteria (eg, did not have a mobile phone, did not reside in Ha Noi, did not smoke cigarettes). Table 1 presents the characteristics of cigarette-only and dual users. Among the 672 participants, 49.7% smoked cigarettes only (n = 334) and 50.3% smoked both cigarettes and waterpipe (n = 338). Most participants were male with an average age of 44.4 years. Education levels were lower among dual users, with nearly half (49.7%) having no schooling or only primary/secondary education, compared to 37.7% of cigarette-only smokers (P = 0.001). Most dual users (92.2%) reported an annual household income of less than 300 million Vietnamese Dong (VND) (∼12 000 USD), compared to 85.8% of cigarette-only smokers (P = 0.012).

Table 1.

Characteristics of PLWH Who Use Cigarettes Only and Dual Users (n = 672)

	Type of tobacco userMean (SD) or n (%)
	Cigarette-only n = 334 (49.7%)	Dual user n = 338 (50.3%)	P-value	Total (N = 672)
Age (years)	44.2 (8.12, 21-71)	44.6 (6.03, 19-68)	0.665	44.4 (7.14, 19-71)
Male gender	312 (93.4%)	335 (99.1%)	<0.001	647 (96.3%)
Education			0.001
No school/Primary/Secondary school	126 (37.7%)	168 (49.7%)		294 (43.8%)
High school (Grade 10-12)	131 (39.2%)	123 (36.4%)		254 (37.8%)
Vocational training/College/University	77 (23.1%)	47 (13.9%)		124 (18.4%)
Household income in past 12 months			0.008
<300 million VND (∼1200 USD)	283 (85.8%)	306 (92.2%)		589 (87.6%)
Equal to or more than 300 million VND (∼1200 USD)	47 (14.2%)	26 (7.8%)		73 (11.0%)
Marital status			0.345
Single/Never Married/Divorced/Separated/Widowed	146 (43.7%)	160 (47.3%)		306 (45.5%)
Married	188 (56.3%)	178 (52.7%)		366 (54.5%)
Lives alone	34 (10.2%)	27 (8.0%)	0.545	61 (9.1%)
Household smoking rules			0.006
Allowed everywhere in the home	174 (52.1%)	217 (64.2%)		391 (58.0%)
Allowed in some areas in the home	134 (40.1%)	102 (30.2%)		236 (35.0%)
Smoking was not allowed	26 (7.8%)	19 (5.6%)		45 (7.0%)
Self-reported health status			0.011
Excellent/Very good/Good	116 (34.7%)	87 (25.7%)		203 (30.2%)
Fair/Poor	218 (65.3%)	251 (74.3%)		469 (69.8%)
Symptoms of depression (CESD-8 >= 9)	127 (38.0%)	123 (36.4%)	0.661	250 (37.2%)
Tobacco and substance use behavior characteristics
Nicotine dependence score (FTND, 0-10)	4.11 (2.43)	5.67 (2.20)	<0.001	4.90 (2.44)
Alcohol consumption (AUDIT-C, 0-12)			0.773
Not hazardous (<3 for females, <4 for males)	144 (43.1%)	142 (42.0%)		286 (42.6%)
Hazardous drinking (>=3 for females, >=4 for males)	190 (56.9%)	196 (58.0%)		386 (57.4%)
Last 3-month drug use	40 (12.0%)	69 (20.4%)	0.003	109 (16.2%)
Risk perception and related behaviors
Perceived harm from smoking cigarettes and/or waterpipe			<0.001
Cigarettes and waterpipe are equally harmful	214 (64.1%)	190 (56.2%)		404 (60.1%)
Cigarettes are more harmful	98 (29.3%)	142 (42.0%)		240 (35.7%)
Waterpipe is more harmful	22 (6.6%)	6 (1.8%)		28 (4.2%)

CSED-8: Centre for Epidemiology Scale for Depression; FTND: Fagerstrom Test for Nicotine Dependence; AUDIT-C: Alcohol Use Disorders Identification Test – Consumption.

Note. Income and recent drug use variables do not add up to 100% because 10 participants were missing data for income and 1 for drug use.

Dual users were more likely to report flexible household smoking rules, with 64.2% of dual users reporting that smoking was allowed anywhere in their home compared to 52.1% of cigarette-only smokers (P = 0.006). Dual use was associated with poorer self-reported health status; 74.3% of dual users rated their health as fair or poor compared to 65.3% of participants who used only cigarettes (P = 0.014).

Dual users reported higher nicotine dependence scores 5.67 (SD = 2.20) compared to cigarette-only smokers 4.11 (SD = 2.43) (P < 0.001). Additionally, recent drug use was higher among dual users (20.4%) than people who used only cigarettes (12.0%) (P = 0.003). Dual and cigarette-only users differed significantly in their perceptions about the comparative risk of waterpipe and cigarette use. Dual users were more likely to report that cigarettes are more harmful than waterpipe use compared with those who used cigarettes only (42.0% vs 29.3%; P < 0.001).

Discussion

Almost half of the patient population in this study were dual users. A 2021 systematic review of national data on current dual or poly-tobacco use across 48 countries found a higher prevalence of dual and poly-tobacco use in LMICs compared to high-income countries (HIC), with dual tobacco use being the highest in South-East Asia.¹³ These high rates of dual use are similar to those found among a general population receiving primary care in a rural province in Viet Nam.¹⁸ There is a lack of similar data on patterns of tobacco use among PLWH in LMICs.¹

In this study, dual use was associated with a lower level of education and lower household income. These findings are consistent with studies conducted among PLWH in HIC settings and among the general population in LMICs.^30,31 Dual users in this study were also more likely to report higher rates of recent drug use, and higher levels of nicotine dependence. A national survey of a general population of US adults similarly found an association between higher levels of nicotine dependence and poly-tobacco use.^30,32 Both active substance use and higher nicotine dependence levels are associated with less success in quitting,³³ and therefore have implications for designing interventions for this population.

Consistent with previous literature, the majority of study participants believed that waterpipe was less harmful than cigarette use.^{12,15,17,34,35} A national survey conducted in 2015 among the general population in Viet Nam found that cigarette and waterpipe smokers have the perception that waterpipe use is less harmful and that this belief may influence intention to quit.¹⁷ The current study further adds to the literature by demonstrating that dual users may differ from cigarette-only users in their perceptions about the harms associated, which may, in turn, inform approaches to reducing tobacco use among PLWH. Given this widespread misconception, provider-led smoking cessation counseling should incorporate education about waterpipe-related harms to strengthen the effectiveness of counseling.

Viet Nam’s comprehensive tobacco control program has resulted in significant declines in the prevalence of tobacco use.¹⁴ However, the lack of regulatory/policy framework specific to waterpipe has hindered progress in addressing high rates of dual and waterpipe-only use in countries like Viet Nam where the prevalence of poly-tobacco use is high.¹⁰ Moreover, addressing the growing burden of tobacco-related illnesses among PLWH will require integrating tobacco use treatment and HIV care to include screening, brief counseling and referral to additional smoking cessation services for both cigarette and waterpipe users. Finally, the paucity of publications that examine correlates tobacco use and dual tobacco use, specifically among PLWH, limits comparisons across and within regions.²⁹ In addition, a lack of consistency in defining poly and dual use creates challenges in interpreting findings. A shared taxonomy is needed to support comparisons across regions and to accurately track changes in prevalence of poly-tobacco use and inform tobacco policy.

There are some limitations of this study. First, there is no validated tool to assess dependence for the type of waterpipe used that is more popular in Southeast Asia.³⁶ Second, we combined the results for every day and someday waterpipe users, which may have masked differences across the correlates analyzed. Third, while a power analysis was conducted for the parent RCT to detect differences in smoking cessation outcomes between intervention arms, the baseline sample used in this secondary analysis (n = 672) was not specifically powered to detect differences between cigarette-only users and dual users. Fourth, the study was conducted among HIV clinics in an urban area of Viet Nam and may not be generalizable to rural populations. Finally, the trial includes a very small sample of women. However, this is consistent with the prevalence of tobacco use among women in Viet Nam, which is less than 2%.³⁷

Conclusion

Among PLWH receiving care in HIV clinics in Viet Nam, over half were using both waterpipe and cigarettes. Differences across cigarette and dual users have implications for both policy and treatment approaches tailored to the unique needs of PLWH in resource-limited settings.

Footnotes

ORCID iDs

Reet Kapur

Nam Nguyen

Gloria Guevara Alvarez

Trang Nguyen

Charles M. Cleland

Mari Armstrong-Hough

Ethical Considerations

This study used baseline data from a randomized controlled trial that is approved by the Institutional Review Boards of New York University, USA and the Institute of Social and Medical Studies, Viet Nam.

Consent to Participate

Informed written consent was obtained from all participants prior to enrollment in the parent study.

Author Contributions

DS, NN, and TN conceptualized the paper. CC and RK were responsible for analyzing the data. DS and RK were responsible for drafting and editing the manuscript. All authors read and approved the final submission.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study used baseline data from a randomized controlled trial funded by the National Cancer Institute (R01CA240481).

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Data Availability Statement

This study’s data includes sensitive patient information, such as HIV status, and cannot be publicly shared due to ethical and legal restrictions. Data are available upon reasonable request. Researchers may submit data requests to Donna Shelley (donna.shelley@nyu.edu) or Nam Nguyen (ntnam@isms.org.vn) with a brief proposal outlining the intended use.

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