Nearly 50% of U.S. cigarette smokers smoke ≤ 10 cigarettes per day (CPD) and are considered light smokers. Most light smokers will either maintain a chronic light smoking habit or increase their level of smoking during their lifetime. Importantly, light smokers are at risk for adverse health consequences and increased all-cause mortality. While multiple factors such as reinforcement behavior, diminished autonomy, economic constraints and tobacco control policies influence light smoking, nicotine dependence appears particularly important in 5 to 10 CPD smokers. Despite the high prevalence of light smoking and its increased healthcare burden, few studies have evaluated the efficacy of pharmacotherapy for this group of smokers. Varenicline, which targets symptoms of nicotine dependence, has been shown to increase smoking abstinence rates in moderate to heavy smokers (≥ 10 cigarettes per day). However, varenicline has not been evaluated in subjects who smoke < 10 CPD. In the current proposal we will investigate the efficacy of varenicline for smoking cessation in 5 to 10 CPD light smokers who wish to quit. This study will be conducted as a double-blind, placebo-controlled, randomized clinical trial at the Mayo Clinic, enrolling 224 eligible participants who smoke 5 to 10 CPD. Participants will receive behavior therapy and either varenicline or placebo for 12 weeks with follow up through 26 weeks. We will determine if varenicline increases smoking abstinence in light smokers at end-of-treatment and 26 weeks as compared to placebo.
The purpose of this study is to determine if varenicline is effective in treating tobacco dependence in adults who smoke 5-10 cigarettes per day.