Should all smokers use combination smoking cessation pharmacotherapy? Using novel analytic methods to detect differential treatment effects over 8 weeks of pharmacotherapy.

INTRODUCTION: Combination pharmacotherapy for smoking cessation has been shown to be more effective than monotherapy in meta-analyses. We address the question of whether combination pharmacotherapy should be used routinely with smokers or if some types of smokers show little or no benefit from combination pharmacotherapy versus monotherapy. METHODS: Two smoking cessation trials were conducted using the same assessments and medications (bupropion, nicotine lozenge, nicotine patch, bupropion + lozenge, and patch + lozenge). Participants were smokers presenting either to primary care clinics in southeastern Wisconsin for medical treatment (Effectiveness trial, N = 1,346) or volunteering for smoking cessation treatment at smoking cessation clinics in Madison and Milwaukee, WI (Efficacy trial, N = 1,504). For each trial, decision tree analyses identified variables predicting outcome from combination pharmacotherapy versus monotherapy at the end of treatment (smoking 8 weeks after the target quit day). RESULTS: All smokers tended to benefit from combination pharmacotherapy except those low in nicotine dependence (longer latency to smoke in the morning as per item 1 of the Fagerström Test of Nicotine Dependence) who also lived with a spouse or partner who smoked. CONCLUSIONS: Combination pharmacotherapy was generally more effective than monotherapy among smokers, but one group of smokers, those who were low in nicotine dependence and who lived with a smoking spouse, did not show greater benefit from using combination pharmacotherapy. Use of monotherapy with these smokers might be justified considering the expense and side effects of combination pharmacotherapy.