Use of heated tobacco products where their use is prohibited.

Introduction: Stealth use implies using tobacco products where their use is prohibited. This paper aimed to investigate stealth use of heated tobacco products (HTPs) in terms of its prevalence and associated factors.

Methods: An online survey was conducted to investigate the use of HTPs in 7000 randomly selected participants (2300 men and 4700 women, aged 20-69 years) from the database registered with an online-research company; we used a sex ratio of 1:2, considering a low female prevalence of tobacco use in Korea. Of total participants, 574 (8.2%) were current HTP users. Among them, we identified the participants who had practised HTPs stealth use, and evaluated associated factors using multivariable Poisson regression.

Results: A total of 574 participants were identified as current HTP users, and 455 (79.2%) reported stealth use of HTPs during the month before the survey. Stealth use was more frequent in dual cigarette users (HTPs and electronic cigarettes (ECs); adjusted prevalence ratio (aPR) 1.33, 95% CI 1.16 to 1.52) and triple users (HTPs, ECs and combustible cigarettes; aPR 1.18, 95% CI 1.04 to 1.33), as compared with single-HTP users. Stealth use was more prevalent among participants who agreed with allowing indoor HTP use (aPR 1.18, 95% CI 1.11 to 1.26).

Conclusion: Stealth use was prevalent among current HTP users, especially among the poly-users of tobacco products. Considering the positive relationship between an agreement with allowing indoor use of HTPs and stealth use, a campaign to promote change in attitudes of HTP users about their indoor use may be warranted to protect non-users.