Evaluation of the cognitive behavioral smoking reduction program "Smoke_less": a randomized controlled trial.

The vast majority of smokers are unable or unwilling to quit, but many are open to reducing smoking. No treatment options exist for these smokers besides medication-based therapies. Thus, this study investigated the efficacy of a cognitive behavioral therapy (CBT) smoking reduction program, Smoke_less. A sample of 155 outpatient smokers aged 18-70 years was recruited at the Tobacco Dependence Outpatient Clinic of the Medical Center of the University of Munich, Germany, and randomly assigned to the experimental group (Smoke_less: four weekly CBT group sessions and two telephone calls over 5 weeks, n = 51), active comparator group (one 15-minute counseling session, n = 49), or waiting control group (no intervention during the study, n = 55). The primary endpoint was a ≥50% smoking reduction in the intention-to-treat group 1 week and 6 months after the intervention. We evaluated also abstinence rates at follow-up. Significantly more participants in the Smoke_less group had reduced smoking ≥50% compared to the waiting group at 1 week [OR 7.59 (2.59-22.19)] and 6 months [OR 5.00 (1.68-14.84)] and compared to the active comparison group at 1 week [OR 8.58 (2.67-27.31)] but not at 6 months [OR 1.73 (0.71-4.20)]. We found no significant effects on abstinence rates. The CBT smoking reduction program Smoke_less is effective for smoking reduction but is superior to brief counseling only in the short term. Further research is required to improve its efficacy in long-term smoking reduction to provide a valid, non-medication-based alternative to smokers unable or unwilling to quit. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT02337400.