Association between heated tobacco product use and quitting combustible cigarette smoking among Korean adults.

Introduction: Combustible cigarette (CC) smokers often use heated tobacco products (HTPs) to quit CC smoking; however, the role of HTPs in quitting CC smoking is uncertain. We evaluated the link between HTP use and quitting CC smoking considering the intensity of HTP use among a large nationally representative sample of Korean adults.

Methods: We performed a cross-sectional study using data from the 2019 Community Health Survey in Korea. A total of 46,781 adult participants (current CC smokers and former CC smokers' < 5 years) were included and Poisson regression analysis was performed to evaluate the association between HTP use and quitting CC smoking among ever CC smokers.

Results: In ever CC smokers, compared with never HTP use, current daily HTP use was positively associated with quitting CC smoking (< 1-year; prevalence ratio (PR) = 1.63, 95% confidence interval (CI) = 1.36-1.96, 1-5 years; PR = 1.47, 95% CI = 1.36-1.60), whereas current non-daily HTP use showed an inverse association with quitting CC smoking (< 1-year; PR = 0.18, 95% CI = 0.12-0.29, 1-5 years; PR = 0.23, 95% CI = 0.17-0.31). Former HTP use was positively associated with short-term quitting CC smoking (PR = 1.38, 95% CI = 1.18-1.63), but negatively related to quit CC smoking after 1 year (PR = 0.81, 95% CI = 0.74-0.88).

Conclusions: Daily use of HTPs appeared to be related to the increase in quitting CC smoking, but discontinuation of HTP use was significantly associated with the recurrence of CC smoking among former HTP users of 1-5 years.

Implications: Among ever CC smokers, daily use of HTPs was positively associated with quitting CC smoking, but non-daily use of HTPs was inversely associated with quitting CC smoking. Former HTP use was linked to an increased likelihood of short-term quitting CC smoking but was significantly associated with CC smoking relapse after 1 year.