Population effectiveness of pharmaceutical aids for smoking cessation: what is associated with increased success?

Although nicotine replacement therapy (NRT) has shown efficacy in randomized controlled trials, population effectiveness has appeared to diminish after it became available over the counter. The present study examined the population effectiveness of bupropion. It also examined whether population effectiveness of pharmaceutical-aid use in general (NRT, bupropion, or both) might be influenced by environmental factors: Having a smoke-free home (possible indication of motivation to quit) or no other smoker in the household. Data from the large population-based cross-sectional 1999 and 2002 California Tobacco Surveys were combined to improve statistical power for subgroup analyses of duration of abstinence following the most recent quit attempt in the past year. Moderate-to-heavy daily smokers (at least 15 cigarettes/day) a year prior to the survey (N = 2,640) were the main focus. A Cox proportional-hazards analysis suggested that bupropion was effective, perhaps even in the longer term. Further analyses identified significant interactions on abstinence duration between having a smoke-free home and any pharmaceutical-aid use (NRT, bupropion, or both), and between having a smoke-free home and no other smoker in the household. Although pharmaceutical aids may have had a slight short-term benefit if the home was not smoke free, they appeared particularly effective if the home was smoke free, both in the short and longer term. The California population experience supports the policy that programs subsidizing pharmaceutical aids to help smokers quit (particularly bupropion, if appropriate) should target highly motivated smokers who have already taken a behavioral action, such as implementing a smoke-free home.