Behavioral support by ex-smoking peers using instant messaging for smoking cessation: a randomized controlled trial

Abstract

<h3>Background</h3><p>Peer support could be beneficial for smoking cessation. Randomized controlled trial (RCT) evidence on mobile-based behavioral support by ex-smoking peers on smoking cessation in community people who smoke is lacking.</p><h3>Research Question</h3><p>Is mobile-based behavioral support provided by ex-smoking peers effective in promoting smoking cessation among community people who smoke?</p><h3>Study Design and Methods</h3><p>A RCT was conducted on people who smoked daily under the Hong Kong Quit-to-Win Contest 2021. All participants received brief smoking cessation advice at baseline. Each participant in the intervention group joined a 3-person chat group of instant messaging apps (e.g., WhatsApp), which consisted of the people who smoked, a smoking cessation advisor and a trained ex-smoking peer who had quit smoking ≥ 1 year. Personalized behavioral support lasted 3 months through the chat group by ex-smoking peers, including experiences of quitting strategies, coping with withdrawal symptoms, use of smoking cessation services, and encouragement. The control group received 6 smoking cessation text messages and follow-up reminders. The primary outcome was biochemically validated abstinence at 6 months after intervention initiation. Analysis was by intention-to-treat using Poisson regression with robust variance.</p><h3>Results</h3><p>From June to September 2021, 1105 participants were randomly assigned to the intervention (n=553) and control (n=552) groups. At 6 months, compared to the controls, the intervention group showed a non-significant increase in biochemically validated smoking abstinence (8·9% vs. 6·7%; RR 1·32, 95% CI 0·88, 1·99), and more usage of smoking cessation services (14·5% vs. 10·0%; RR 1·45, 95% CI 1·05, 2·00). In the intervention group, participants engaged in instant messaging support showed much more validated abstinence (22·2% vs. 4·9%; RR 4·52, 95% CI 2·66, 7·68).</p><h3>Interpretation</h3><p>Behavioral support by ex-smoking peers via instant messaging was potentially effective and should be improved to increase smoking abstinence.</p><h3>Clinical trial registration</h3><p>ClinicalTrial.gov NCT 04909320</p>