UNC researchers: Benefits of varenicline (Chantix) may balance certain risks
CHAPEL HILL, N.C. – The U.S. Food and Drug Administration (FDA) has approved the smoking cessation medication varenicline (Chantix) as an effective aide in helping people quit smoking, including those with cardiovascular disease, although it cautions that varenicline may also be associated with a small, increased risk of certain cardiovascular adverse events in such patients.
Some researchers have suggested that varenicline shouldn’t be used at all because of these potential increased cardiovascular risks. But two physician-researchers at the University of North Carolina at Chapel Hill School of Medicine believe that a new analysis of potential risks against proven health outcomes provides more complete data for such decisions.
Christine E. Kistler, MD, MASc, and Adam Goldstein, MD, MPH, discuss in a commentary published online March 15 by the journal Nicotine & Tobacco Research ways that clinicians can better have conversations about the balance between any potential short-term increased risk of adverse cardiovascular events compared to the overall long-term reduction in the risk of death that results from smoking cessation and use of the drug.
Dr. Kistler and Goldstein calculated these potential short-term risks and longer term benefits in terms that providers and patients can better discuss. For instance, they calculate that if the research on adverse cardiovascular events and varenicline were true, then one additional woman has an adverse cardiovascular event over a year for every 345 women who take varenicline. They also calculate the benefit of smoking cessation with varenicline on mortality, showing that one additional life is saved over ten years for every 238 people who take a course of varenicline.
“We believe this information will allow clinicians to appropriately and adequately describe the risk and benefit of varenicline use in terms of adverse cardiovascular events and mortality reduction, terms that patients and their doctors more readily understand,” said Dr. Kistler, lead author of the commentary.
“Randomized controlled trials show that varenicline helps significantly more people quit smoking than would quit without the medication” notes Dr. Goldstein, director of tobacco cessation programs in the UNC Department of Family Medicine “Any increased risks of varenicline use should be weighed against known health outcomes from cessation. This analysis allows us to have a more meaningful conversation with patients.”
The bottom line for clinicians, assuming an elevated odds of adverse cardiovascular events with varenicline as published, is that just over approximately four additional lives are saved over 10 years at a cost of approximately three additional adverse cardiovascular events that occur in the first year.
“These calculations should help clinicians to avoid throwing the baby out with the bathwater,” says Dr. Kistler.
This commentary received no external funding or support. Dr. Kistler has an institutional career development award from the Agency for Healthcare Research and Quality. Dr. Goldstein has an unrestricted educational grant from Pfizer through the UNC School of Medicine to support development of inpatient tobacco cessation programs, and he has participated on Advisory Boards for Boehringer and Pfizer Pharmaceuticals.