Abrupt versus gradual smoking cessation with pre-cessation varenicline therapy for Chinese treatment-seeking smokers: A retrospective, observational, cohort study

INTRODUCTIONThis study aimed to explore the efficacy of abrupt and gradual smoking cessation with pre-cessation varenicline therapy.METHODS A total of 278 smokers who experienced moderate-to-severe nicotine dependence and visited a Chinese smoking cessation outpatient clinic from March 2017 to February 2021 were enrolled.This was a retrospective, observational, cohort study.Participants were divided into two groups by the cessation strategy they received: the abrupt cessation group (n=139, tobacco was not controlled during the first 3 weeks before the target cessation date and smoking was entirely discontinued on the 22nd day) and the gradual cessation group (n=139, tobacco was gradually reduced in the first 3 weeks before the target cessation date and smoking was discontinued on the 22nd day).The abstinence rates were compared between groups (7-day point prevalence abstinence rates at 1, 3 and 6 months post-treatment; and 1-month and 3-month continuous abstinence rates of 6-month follow-up).Possible factors that influence efficacy, reasons for smoking cessation failure, and associated adverse events were also analyzed.RESULTS No significant difference in the 7-day point prevalence abstinence rates at 1, 3 and 6 months post-treatment was observed between the groups (p>0.05).The 1-month continuous abstinence rate of the gradual cessation group was higher than that of the abrupt cessation group (51.1% vs 31.7%;χ 2 =10.812, p=0.001).The 3-month continuous abstinence rate of the gradual cessation group was also higher than that of the abrupt cessation group (42.4% vs 27.3%; χ 2 =6.983, p=0.008).Abrupt cessation was a risk factor for successful smoking cessation than gradual cessation (AOR=2.39;95% CI: 1.15-3.85,p=0.013),the motivation of 'prevention and treatment of own diseases' reduced the risk of incomplete abstinence (AOR=0.87;95% CI: 0.38-0.99,p=0.049).The incidence of adverse events was higher in the abrupt cessation group than in the gradual cessation group.The incidence rates of nausea and insomnia were statistically significant differences.CONCLUSIONS Compared with abrupt cessation, gradual smoking cessation with precessation varenicline therapy produced higher abstinence rates and relatively milder withdrawal symptoms.