Global Patterns and Prevalence of Dual and Poly-Tobacco Use: A Systematic Review

INTRODUCTION: Improving understanding of the epidemiology of dual and poly-tobacco product use is essential for tobacco control policy and practice. The present study aimed to systematically review existing epidemiologic evidence on current dual and poly-tobacco use among adults globally. METHODS: We systematically searched online databases for studies published up to June 30, 2020. We included quantitative studies with measures of nationally representative prevalence of current dual or poly-tobacco use among adults. Prevalence estimates for each country were extracted manually and stratified by WHO regions and World Bank income classifications. RESULTS: Twenty studies with nationally representative prevalence data on current dual or poly-tobacco use in the adult population across 48 countries were included. Definitions of dual and poly-tobacco use varied widely. Prevalence of dual and poly-tobacco use was higher in low- and lower-middle-income countries compared to other higher-income countries. Current dual use of smoked and smokeless tobacco products among males ranged from 0.2% in Ukraine (2010) and Mexico (2009) to 17.9% in Nepal (2011). Poly-tobacco use among males ranged from 0.8% in Mexico (2009) and 0.9% in Argentina (2010) to 11.4% in the United Kingdom and 11.9% in Denmark in 2012. Dual tobacco use was generally higher in South-East Asia; poly-tobacco use was prevalent in Europe as well as in South-East Asia. CONCLUSIONS: This is the first systematic review of the prevalence estimates of dual and poly-tobacco use among adults globally. The results of the current study could significantly help health policy makers to implement effective tobacco control policies. IMPLICATIONS: This study demonstrates that dual/poly-tobacco use is common in many countries of the world, and highlights the need for in-depth exploration of this field in future studies, especially in high prevalence regions such as South-East Asian and European countries. In light of this, the global tobacco control community and health authorities should also agree upon a consistent operational definition of dual and poly-tobacco use to propel research and improve surveillance of dual/poly-use in health surveys for better communication and understanding of these phenomena.