Smoking-related behaviour changes among Korean men after the 2015 tobacco price increase: assessing the implications for the tobacco endgame using a reconstructed retrospective cohort study

OBJECTIVES: To examine the effect of Korea’s 2015 tax policy, discuss its effectiveness and limitations and present future directions for tax policy in the context of the tobacco endgame. DESIGN: A retrospectively reconstructed cohort study. SETTING: Korea, August 2014–October 2015. PARTICIPANTS: The study examined 41,605 male smokers aged 19 years and older who participated in the 2015 Korea Community Health Survey. MEASURES AND ANALYSIS: Binary and multinomial logistic regression was used to assess the impact of the tax policy on smoking-related behaviour. We adjusted for demographic and health-related variables. RESULTS: Among 41,605 men who were smokers in 2014, 15,499 (35.85%, weighted) reported being affected by the price increase. Of all smokers, 1,772 (3.96%, weighted) reported quitting smoking because of the tobacco price increase. Others reduced their smoking amount (n=9,714, 22.48%, weighted) or made other changes such as switching brands (n=4,013, 9.41%, weighted). An additional 2,401 smokers (5.72%, weighted) quit smoking for reasons other than the tobacco price increase. Compared with those in the highest quintile of household income, the odds that those in the lowest quintile quit smoking due to the price increase were almost twice as high (OR=1.98, 95% CI 1.54 to 2.54). CONCLUSIONS: Korea’s 2015 tobacco price increase affected a significant number of smokers within a year, especially in the lowest income group, inducing some to quit or reduce their smoking amount. However, more smokers quit for reasons independent of the price change. Tax policy can effectively reduce smoking, but needs to be combined with other policies for optimal results.