Comparative Effectiveness of Smoking Cessation Medications: A National Prospective Cohort From Taiwan

Background and objective: Relative effectiveness of smoking cessation medications—varenicline, bupropion and nicotine replacement therapy (NRT)—remains unclear among smokers in real-world settings. Evidence in females and smokers with light/moderate nicotine dependence is particularly insufficient. This study compared the effectiveness of varenicline, bupropion or NRT gum relative to NRT patch, in achieving abstinence among recent quitters. Methods: In a national smoking cessation program in Taiwan (2012–2015), a cohort of 11,968 participants received varenicline (n = 5,052), bupropion (n = 823), NRT gum (n = 1944) or NRT patch (n = 4,149). The 7-day, 1-month or 6-month point-prevalence was calculated based on self-reported last smoking event via telephone interview after 6 months. Logistic regression modellings estimated odds ratios (OR) and 95% confidence intervals (CI) for achieving abstinence using different modalities (NRT patch as referent). Models included age, sex, education, marital status, geographic region, smoke-years, nicotine-dependence level, medical institution, number of clinic visits and medication use duration. Analyses were further stratified by sex and dependence severity. Results: Participants were predominantly male (83%) with a mean age of 43.7±12.6 years. Varenicline users were more likely than NRT patch users to achieve abstinence, based on 7-day point-prevalence (OR = 1.30, CI: 1.19–1.44), 1-month point-prevalence (OR = 1.36, CI: 1.24–1.50) or 6-month point-prevalence (OR = 1.30, CI: 1.14–1.47). Compared with NRT patch, varenicline was associated with greater odds of being abstinent in women (OR = 1.29, CI: 1.01–1.65), men (OR = 1.31, CI: 1.18–1.46), those with light/moderate dependence (OR = 1.42, CI: 1.24–1.63) or smokers with severe dependence (OR = 1.19, CI: 1.04–1.37), based on 7-day point-prevalence. Differences in effectiveness were not observed between users of bupropion, NRT gum and NRT patch. Conclusions: In smoking cessation clinics in Taiwan, varenicline users reported higher abstinence rates than NRT patch users after 6 months. Women and smokers with light/moderate nicotine dependence may also benefit from varenicline in actual clinical practice.