Last year a review of clinical trials of varenicline (Chantix) concluded that this smoking cessation medicine may cause an increased risk of serious cardiovascular events among smokers trying to quit and this was widely reported, including on
WebMD . However, last week a
new study , including all 22 placebo-controlled trials of varenicline published to date, found no significant increase in serious cardiovascular problems associated with use of varenicline. In this study a serious cardiovascular event included any ischaemic or arrhythmic adverse cardiovascular event (myocardial infarction, unstable angina, coronary revascularisation, coronary artery disease, arrhythmias, transient ischaemic attacks, stroke, sudden death or cardiovascular related death, or congestive heart failure).
Overall, the study found that 0.63% (34/5431) of people using varenicline experienced a serious cardiovascular event, as compared with 0.47% (18/3801) of those using placebo pills. This new study possibly came to a different conclusion than the previous review on this topic because it focused on events occurring while people were taking the drug and for 30 days thereafter. The previous study included events occurring throughout the whole duration of follow-up and did not correct for the fact that varenicline treated patients were more likely to participate in the follow-ups (and therefore report events), partly because they were much more likely to quit smoking.
The study authors, Drs Judith Prochaska and Joan Hilton of the University of California, concluded that, "Our meta-analysis of treatment emergent, cardiovascular serious adverse events, ... indicates that the risk of these events associated with varenicline use is small, and statistically and clinically insignificant."
I wonder if WebMD is going to report this new finding?