Level 1: Likely reliable evidence
Guidelines for secondary prevention of cardiovascular disease (CVD) from the American Heart Association and the American College of Cardiology call for complete smoking cessation and complete avoidance of environmental tobacco smoke. While the second goal may be difficult to accomplish, a new randomized trial with 714 patients provides strong evidence that varenicline (Chantix, Champix) is effective for helping people with heart disease stop smoking (Circulation. 2010;121:221-229). Though varenicline has been widely tested in healthy individuals, this is the first trial specifically addressing smoking cessation in patients with stable CVD. Participants were randomized to varenicline 1 mg orally twice daily vs. placebo for 12 weeks and were followed for 52 weeks. All patients received smoking cessation counseling. Carbon monoxide-confirmed continuous abstinence rates were significantly higher for varenicline during weeks 9-12 (47% vs. 13.9%, P <0.0001, NNT 4) and during weeks 9-52 (19.2% vs. 7.2%, P <0.0001, NNT 9). There were no significant differences in all-cause mortality, cardiovascular events, or other serious adverse events, but low event rates limit the study’s power for safety outcomes. The discontinuation rate was higher in the varenicline group (9.6% vs. 4.3%, P <0.05, NNH 18). The most common adverse events included nausea, headache, and insomnia.