A systematic review and meta-analysis was conducted to ascertain the serious adverse cardiovascular effects of varenicline, a widely used smoking cessation drug. Double-blind, randomized controlled trials published through September 2010 (updated March 2011) of at least one week’s duration involving smokers or people who used smokeless tobacco were included. These studies reported on cardiovascular events (ischemia, arrhythmia, congestive heart failure, sudden death or cardiovascular-related death) as serious adverse events associated with the use of varenicline. Data from 14 trials, ranging from 7 to 52 weeks and that involved 8216 participants were analyzed. Varenicline was associated with a significantly increased risk of serious adverse cardiovascular events compared with placebo: 1.06% (52/4908) in the varenicline group versus 0.82% (27/3308) in the placebo group; Peto odds ratio (OR) 1.72, 95% confidence interval (CI) 1.09–2.71. Results of various sensitivity analyses were consistent with those of the main analysis and a no publication bias was detected. There were too few deaths to allow meaningful comparisons of mortality. This meta-analysis raises safety concerns about the potential for an increased risk of serious adverse cardiovascular events associated with the use of varenicline among tobacco users. CMAJ. 2011 Jul 4. PMID: 21727225.
