Effectiveness of Coadministration of Varenicline, Bupropion, and Serotonin Reuptake Inhibitors in a Smoking Cessation Program in the Real-Life Setting

Introduction: Varenicline has a significant impact on the ability to quit smoking. However, patients may have side effects similar to nicotine withdrawal symptoms. The aim of this study was to evaluate the effectiveness of varenicline in monotherapy or in combined therapy with bupropion and/or serotonin reuptake inhibitors (SRIs) in a specific cardiovascular smoking cessation service. Methods: It is an outcome research of 427 patients that received varenicline monotherapy or combined pharmacotherapy and were followed for 52 weeks. Patients were oriented to take varenicline until week 12. During each medical visit, the patients were evaluated and in the cases of mood changes after varenicline use, SRIs were prescribed. Bupropion was combined in patients that did not achieve complete tobacco abstinence in 2 or 3 weeks after starting varenicline use or if the patient presented uncomfortable abstinent symptoms. Results: The success (continuous abstinence rate in 52 weeks) in different drug regimens were: varenicline monotherapy (32.1%), varenicline + bupropion (55.0%), varenicline + SRI (50.6%), and varenicline + bupropion + SRI (57.7%). In a multivariate analysis of successful treatment predictors, compared with varenicline monotherapy, patients who used bupropion + SRI adjuvant treatment had an odds ratio (OR) of 5.05 (1.99-12.80) for a successful treatment response after 1-year follow-up, while patients who used bupropion or SRI had OR of 3.21 (1.68-6.14) and 3.58 (1.98-6.48), respectively. Conclusions: Our results suggest that adjuvant treatment to varenicline therapy may be associated with improved success in smoking cessation, especially in patients with nicotine withdrawal symptoms. These results should be tested in randomized controlled trials.