Association of heated tobacco product use with smoking cessation in Chinese cigarette smokers in Hong Kong: a prospective study.

INTRODUCTION: Heated tobacco products (HTPs) are increasingly popular worldwide, but whether they aid or undermine cigarette abstinence remains uncertain. We examined the predictors of HTP initiation and the prospective association of HTP use with cigarette abstinence in community-based smokers in Hong Kong. DESIGN: Secondary analysis of a randomised clinical trial aimed to evaluate the effectiveness of brief advice and referral for smoking cessation. The interventions were not related to HTP use. PARTICIPANTS AND SETTINGS: 1213 carbon monoxide-verified daily cigarette smokers with intentions to quit or reduce smoking proactively recruited from community sites throughout Hong Kong MAIN EXPOSURE: Current (past 7 day) use of HTP at baseline. MAIN OUTCOME: Self-reported 7-day point-prevalence cigarette abstinence at 6 months (exclusive use of HTP permitted). RESULTS: At baseline, 201 (16.6%) and 60 (4.9%) were ever and current HTP users, respectively. During the 6-month follow-up period, 110 of 1012 (10.9%) never users at baseline initiated HTPs. Younger age and higher education significantly predicted initiation. After adjusting for sociodemographic, smoking-related and quitting-related factors, current HTP use at baseline was not associated with cigarette abstinence at 6 months (adjusted prevalence ratio (aPR) 1.08, 95% CI 0.63 to 1.85). The results were similar in persistent users from baseline to 1-month/3-month follow-up (vs non-users; aPR 1.14, 95% CI 0.57 to 2.29). Use of smoking cessation service between baseline and 3-month follow-up significantly predicted cigarette abstinence (aPR 1.70, 95% CI 1.26 to 2.30). CONCLUSION: HTP use was not associated with cigarette abstinence at 6 months in a community-based cohort of smokers with intentions to quit or reduce smoking. Trial registration details ClinicalTrials.gov, NCT03565796.

Effects of active referral combined with a small financial incentive on smoking cessation: study protocol for a cluster randomised controlled trial.

INTRODUCTION: Evidence-based smoking cessation treatments are effective but underutilised, accentuating the need for novel approaches to increase use. This trial investigates the effects of active referral combined with a financial incentive to use smoking cessation services on smoking abstinence among community smokers. METHODS AND ANALYSIS: This ongoing study is a two-arm, assessor-blinded, pragmatic, cluster randomised controlled trial with follow-ups at 1, 2, 3 and 6 months after randomisation. We aim to enrol 1134 daily smokers from 70 community sites (clusters) in Hong Kong. All participants receive Ask, Warn, Advise, Refer, Do-it-again (AWARD) guided advice and a self-help booklet at baseline. Additionally, participants in the intervention group receive an offer of referral to smoking cessation services at baseline and a small financial incentive (HK$300≈US$38) contingent on using any of such services within 3 months. The primary outcomes are bioverified abstinence (exhaled carbon monoxide <4 ppm and salivary cotinine <10 ng/mL) at 3 and 6 months. Secondary outcomes include self-reported 7-day point prevalence of abstinence, smoking reduction rate, quit attempts and the use of smoking cessation services at 3 and 6 months. Intention-to-treat approach and regression models will be used in primary analyses. ETHICS AND DISSEMINATION: This protocol has been approved by the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster (IRB reference number: UW 18-318). The results of this trial will be submitted for publication in peer-reviewed journals, and the key findings will be presented at national and international conferences. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry NCT03565796.