Umeå University's logo

Background: Tobacco consumption is one of the most significant causes of premature death globally. One out of four men in the world is an active smoker with a total estimate of 933 million current smokers in 2015. Indonesia has one of the highest smoking rates in the world along with Russia and Bangladesh. Smoking was concentrated among the worst-off population in many low-middle income countries. Studies on the determinants of socioeconomic disparities in smoking in Indonesia are currently lacking. This study fills this gap of knowledge by investigating the socioeconomic inequality in smoking and socioeconomic factors explaining the disparities in smoking behaviour among adults aged 15 years old and above in Indonesia.

Methods: This cross-sectional study utilized data from the Indonesia Family Life Survey (IFLS) Wave 5 conducted in 2014-2015. The study included 29,844 individuals aged above 15 years old. The outcome was smoking status (defined as current smokers and never smokers). Socioeconomic status was defined based on wealth index created using Principal Component Analysis on housing characteristics and ownership of assets. Socioeconomic inequalities in smoking were measured using Concentration Index (CI) and graphed as Concentration Curve (CC). The determinants of socioeconomic inequalities in smoking (including socioeconomic, material and psychosocial factors) were assessed using Wagstaff decomposition analysis. All the analyses were conducted separately for men and women.

Result: About 70.3% of men and 2.4% of women was current smokers in Indonesia (p<0.001). The concentration index showed an existing socioeconomic inequalities in smoking behaviour was concentrated among the poorest, and the inequality was more prominent among men (CI: -0.23; 95%CI: -0.26; -0.20) compared with women (CI: -0.05; 95% CI: -0.06; -0.04)). The decomposition analysis indicated that wealth index was the major contributor to socioeconomic inequalities in both gender (men: 26.6%, women: 49.2%).

Conclusion: Smoking is concentrated among the most impoverished population in both genders, and is more prominent among men. The major contributor to the socioeconomic inequalities in smoking is material factors, particularly the wealth index. This study confirms the multi-dimension determinants of smoking inequalities such as the sociodemographic, material, psychosocial, and health factors. Therefore, a comprehensive approach and government commitment to smoking prevention and control are needed to reduce the prevalence of smoking in Indonesia, especially among the most vulnerable group.