Clustering Lifestyle Risk Behaviors among Vietnamese Adolescents and Roles of School: A Bayesian Multilevel Analysis of Global School-Based Student Health Survey 2019

BackgroundAdolescence is a vulnerable period for many lifestyle risk behaviors. In this study, we investigated the clustering of risk behaviors and role of the school health promotion programs among adolescents in Vietnam. MethodsWe analyzed data of 7,541 adolescents aged 13-17y from the 2019 nationally representative Global School-based Student Health Survey, conducted in 20 provinces and cities in Vietnam. We applied the latent class analysis to identify groups of clustering and used Bayesian 2-level logistic regressions to evaluate the effects of school health promotion programs on these clusters. We reassessed the school effect size by incorporating different informative priors to the Bayesian models. FindingsThe most frequent lifestyle risk behavior among Vietnamese adolescents was unhealthy diet ([~]67%), followed by sedentary behavior (37% in boys and 48% in girls) and low fruit/vegetable intake ([~]31%). More than half of students had a cluster of at least two risk factors and a quarter with three risk factors. Latent class analysis detected 18% boys and 15% girls being at high-risk of lifestyle behaviors. Consistent through different priors, high quality of health promotion programs associated with lower the odds of lifestyle risk behaviors (highest quality schools vs. lowest quality schools; boys: Odds ratio (OR) = 0{middle dot}69, 95% Highest Density Interval (HDI): 0{middle dot}49 - 0{middle dot}99; girls: OR = 0{middle dot}62, 95% HDI: 0{middle dot}42 - 0{middle dot}92). InterpretationOur findings demonstrated the clustering of specific lifestyle risk behaviors among Vietnamese adolescents, suggesting a special need for required courses in schools and join interventions that target sex-specific multiple risk behaviors. FundingThe 2019 Global School-based Student Health Survey was conducted with financial support from the World Health Organization. The authors received no funding for the data analysis, data interpretation, manuscript writing, authorship, and/or publication of this article. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSAdolescence is a vulnerable period for many lifestyle risk behaviors which normally cluster and interact to exponentially elevate the risks of non-communicable diseases (NCDs). The school might play an essential role in preventing risk behaviors and motivating healthy lifestyle behaviors for in-school adolescents. We searched on PubMed and Google Scholar to identify peer-reviewed articles published in English between Jan 1, 2000 and November 25, 2020; using keywords ("health behaviors" OR "lifestyle risk behaviors "OR "health risk behaviors" OR "tobacco" OR smok* OR "alcohol" OR "physical activity" OR "physical inactivity" OR "fruit intake" OR "vegetable intake" OR "diet") AND (cluster* OR "co-occurrence") AND ("adolescent" OR "teenager" OR "youth" OR "student"). We complemented the searching database with a manual search on reference lists. We identified 39 studies that evaluated the clustering of risk behaviors among adolescents (Supplemental materials S1). Two-thirds of the studies were conducted in high-income countries. The evidence from low- and middle-income countries is currently limited in some countries; however, most of these studies used descriptive techniques to analyze the co-occurring behaviors, i.e., treating the effects of risk behaviors equally or computing the observed prevalence-to-expected prevalence ratio, which hardly evaluates the underlying association among these co-occurrences. Furthermore, no studies have focused on the role of school health promotion programs in preventing the high-risk cluster of these behaviors. Added value of this studyOur study is a pioneer in using analytical technique to investigate the clustering pattern of six major lifestyle risk behaviors of NCDs (smoking, drinking, physical inactivity, sedentary behavior, low fruit/vegetable intake, and unhealthy diet) among school-going adolescents in Vietnam. We found more than half of adolescents had a cluster of at least two factors and a quarter had three factors, with the common clusters being unhealthy diet, sedentary behaviors, low fruit/vegetable intake (in girls), and drinking (in boys). Using latent class analysis, we identified 18{middle dot}1% of boys and 14{middle dot}7% of girls were at high-risk pattern of lifestyle behaviors. Consistent across scenarios, Bayesian multilevel models showed that the quality of school health promotion programs was associated with minimizing the high-risk cluster of lifestyle behaviors. Implications of all available evidenceOur findings highlight the need for required courses in school with high-quality content for essential joint knowledge and skills to prevent multiple lifestyle risk behaviors. This becomes urgent as the current curriculum is not required in Vietnam, therefore, although the high prevalence of students completed a module for preventing an individual risk behavior; a limited number of them achieved three such modules. We also emphasize separated intervention for boys and girls since the patterns of lifestyle risk behaviors combination are different by sexes.