Real-world effectiveness of cytisine, bupropion, and nicotine replacement therapy in a smoking cessation clinic: A single-center retrospective cohort study

Abstract

INTRODUCTION Pharmacological treatments such as cytisine, bupropion, and nicotine replacement therapy (NRT) are widely used to support smoking cessation. However, evidence comparing their effectiveness in real-world clinical settings, particularly within smoking cessation outpatient clinics, remains limited. METHODS This retrospective cohort study evaluated smoking cessation outcomes among patients attending a tertiary smoking cessation outpatient clinic, with follow-up assessments conducted at approximately the first, third, and sixth months. The study was conducted between 1 January 2024 and 28 March 2025. Participants received cytisine, bupropion, or NRT in combination with standardized behavioral counseling. Demographic variables, smoking-related characteristics, treatment adherence, adverse effects, and cessation outcomes were assessed. Smoking cessation was defined as self-reported abstinence during follow-up. Adult patients aged ≥18 years who received smoking cessation treatment were included in the study. RESULTS A total of 113 patients were included, of whom 67 (59.3%) successfully quit smoking. Completion of pharmacological treatment was significantly higher among patients who quit smoking compared with those who did not (77.6% vs 30.4%, p<0.001). Cytisine use was more frequent among patients who achieved smoking cessation (58.2% vs 39.1%, p=0.046), whereas bupropion use was higher among those who failed to quit smoking (41.3% vs 20.9%, p=0.019). Nicotine replacement therapy use was not significantly associated with cessation outcomes (p=0.983). Among patients who achieved abstinence, relapse occurred in approximately one-third during follow-up. Improvement in dyspnea was reported more frequently among cytisine users. CONCLUSIONS In this real-world outpatient setting, cytisine was associated with higher smoking cessation success compared with bupropion and NRT. Treatment adherence emerged as a key determinant of cessation outcomes.