Effect of “Cut Down To Quit” on Smoking Cessation: A randomized Controlled Trial

Abstract

BACKGROUND AND OBJECTIVES: Smoking reduction was found not be inferior to abrupt cessation on quitting in smokers with motivation to quit. This study tested a brief smoking reduction intervention without pharmacotherapy assist on smoking abstinence in Hong Kong “Quit to Win” smoking participants in 2014. METHODS: This parallel open-labeled cluster randomized controlled trial (NCT02188433) recruited community adult daily smokers (N=1077) and randomly allocated to “Cut down to quit” (CDTQ) (n=559) or “Quit immediately” (QI) (n=518) group. Randomization was based on recruitment session according to pre-defined random sequences. Smokers in CDTQ group received brief advices on reducing daily cigarette consumption and a self-help card on smoking reduction strategies and coping with craving. The QI group received a brief advice on abrupt quit and a 12-page conventional self-help booklet on smoking cessation. Telephone follow-ups at 1 week, 1, 2, 3 & 6 months were conducted by assessors who were blinded to group allocation. Primary outcome was self-reported 7-day point prevalence quit rates at 3 and 6 months. Self-reported abstinence at 6 months was biochemically validated using exhaled carbon monoxide (<4ppm) and salivary cotinine (<10ng/ml). Intention to treat principle was used. FINDINGS: About 63% and 61% of smoker were followed at 3 and 6-month, respectively. Quit rates at 3-month were similar between CDTQ (7.0%) and QI (10.0%) (odds ratio [OR] =0.67, 95% CI 0.44-1.04,). The corresponding quit rates at 6-month were 9.1% and 10.6% (OR =0.85, 95% CI 0.57-1.26). Both groups had similar validated quit rates (CDTQ 5.4%, QI 5.6%; OR =0.96, 95% CI 0.57-1.62). Smokers in CDTQ (20.9%) were more likely to reduce 50% or more cigarette consumption than QI smokers (14.5%) at 6-month (p <0.01). CONCLUSION: The brief smoking reduction intervention achieved similar quit rates to the conventional quitting advice in adult smokers in Hong Kong. Smoking reduction strategy might have helped some smokers to quit particularly those unwilling to quit abruptly. Funding: Hong Kong Council on Smoking and Health Corresponding Author: Man Ping Wang, The University of Hong Kong, Hong Kong, mpwang@hku.hk