Varenicline and Adverse Cardiovascular Events: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Varenicline is an efficacious smoking-cessation drug. However, previous meta-analyses provide conflicting results regarding its cardiovascular safety. The publication of several new randomized controlled trials (RCTs) provides an opportunity to reassess this potential adverse drug reaction.

We searched MEDLINE, EMBASE, and the Cochrane Library for RCTs that compare varenicline with placebo for smoking cessation. RCTs reporting cardiovascular serious adverse events and/or all-cause mortality during the treatment period or within 30 days of treatment discontinuation were eligible for inclusion. Relative risks (RRs) with 95% CIs were generated by using DerSimonian-Laird random-effects models. Thirty-eight RCTs met our inclusion criteria (N=12 706). Events were rare in both varenicline (57/7213) and placebo (43/5493) arms. No difference was observed for cardiovascular serious adverse events when comparing varenicline with placebo (RR 1.03, 95% CI 0.72-1.49). Similar findings were obtained when examining cardiovascular (RR 1.04, 95% CI 0.57-1.89) and noncardiovascular patients (RR 1.03, 95% CI 0.64-1.64). Deaths were rare in both varenicline (11/7213) and placebo (9/5493) arms. Although 95% CIs were wide, pooling of all-cause mortality found no difference between groups (RR 0.88, 95% CI 0.50-1.52), including when stratified by participants with (RR 1.24, 95% CI 0.40-3.83) and without (RR 0.77, 95% CI 0.40-1.48) cardiovascular disease.

We found no evidence that varenicline increases the rate of cardiovascular serious adverse events. Results were similar among those with and without cardiovascular disease. Given varenicline's efficacy as a smoking cessation drug and the long-term cardiovascular benefits of cessation, it should continue to be prescribed for smoking cessation.