Characterization of Respiratory Systems Among Youth Using Heated Tobacco Products in Hong Kong

Importance Heated tobacco products (HTPs) are promoted as less harmful than combustible cigarettes but epidemiological evidence is scarce, especially in youth. Objective To investigate the associations of persistent respiratory symptoms with HTP use, cigarette use, and dual use among Hong Kong youth. Design, Setting, and Participants This was a territorywide cross-sectional school-based survey conducted from October 2018 to July 2019 using an anonymous questionnaire. Schools were randomly invited from a proportionate stratified sample in all 18 districts of Hong Kong. Poisson regression models using generalized estimating equations yielded adjusted prevalence ratios (APRs) of respiratory symptoms in (1) former and current HTP (vs never) users in the whole sample and stratified by cigarette use status and (2) exclusive HTP and dual users vs exclusive cigarette users. Statistical analysis was performed from October 2020 to March 2021. Exposures Former and current use of cigarettes, HTPs, e-cigarettes, and other tobacco products. Main Outcomes and Measures Respiratory symptoms for 3 consecutive months in the past 12 months