Abstract P135: Varenicline and the Risk of Adverse Cardiovascular Events: A Population-Based Cohort Study
Background: Clinical trial results suggest that varenicline is the most efficacious smoking cessation therapy. However, its cardiovascular safety is controversial, with recent meta-analyses providing conflicting results. Our objective was to compare the effect of varenicline to that of bupropion on the risk of cardiovascular events.
Methods: We conducted a population-based cohort study of new users of varenicline or bupropion using data extracted from the UK’s Clinical Practice Research Datalink (CPRD) and Hospital Episode Statistics. Our primary endpoint was a composite of myocardial infarction, coronary revascularization, stroke, and all-cause mortality. An ‘as-treated’ analysis with a Cox proportional hazards model was used, with patients censored 7 days after the end of their last prescription or upon switching smoking cessation drugs. In secondary analyses, we compared varenicline and bupropion to nicotine replacement therapy (NRT) in pairwise comparisons. All analyses used high-dimensional propensity scores to adjust for potential confounding.
Results: Our primary cohort included 90,522 varenicline users and 12,640 bupropion users. The mean age was 44 years, and 48% were men. The mean treatment duration was 45 days. A total of 128 events occurred among varenicline users, and 15 occurred among bupropion users. Although estimates suggest that varenicline may modestly increase the risk of cardiovascular events compared to bupropion, they were accompanied by wide 95% CIs (Table). Both varenicline and bupropion users had significantly lower risks of cardiovascular events than NRT users (Table).
Conclusions: While we cannot exclude a modestly increased risk of cardiovascular events with varenicline relative to bupropion, such events remain rare, and both varenicline and bupropion are associated with a decreased risk of cardiovascular events compared with NRT. The long-term benefits obtained due to the increased smoking abstinence with varenicline likely outweigh any increased cardiovascular risk.
Author Disclosures: K.B. Filion: None. S. Dell'Aniello: None. M. Eberg: None. C. Renoux: None. S.S. Daskalopoulou: None. S. Suissa: None.
- © 2014 by American Heart Association, Inc.