Efficacy of smoking cessation in spirometry results of COPD smokers: a randomized controlled clinical trial

BackgroundNicotine replacement therapy (NRT) may be more effective if it is combined with short cognitive-behavioral interventions for smoking cessation in chronic obstructive pulmonary diseasesmokers. Material and methodsTo examine the effectiveness of guided self-change (GSC), in a randomized controlled clinical trial, 57 men ranging from 45 to 77 years old were randomly assigned to three 19-member groups (GSC, NRT, and combined GSC-NRT). The primary data on smoking cessation and pulmonary functions were examined during 29 weeks using General Linear (GEE) Model status, intention-to-treat analysis, and repeated measures ANOVA test. ResultsA total of 9 (47.4%) of the participants in the GSC and combined groups and 4 (21.1%) participants in the NRT group reported total abstinence rate from smoking by the end of 29 weeks. Daily cigarette number was changed from 24 to 4 in GSC group, 26 to 11 in NRT group, and 20 to 6 in combined group. The GEE model revealed that this variable decreased in GSC group more than two other groups significantly (P=0.003). Moreover, the FVC level of the NRT group was lower than the GSC group (P=0.04), and the FEV in the NRT group was lower than GSC group (P=0.02). Furthermore, the level of FEV1/FVC act/pred in the NRT group was lower than GSC group (-6, 95% CI: -10.4-(-1.5), P=0.008) and it was also lower in the combined group than the GSC group (-6, 95% CI: -11.3-(-0.5), PV=0.03). ConclusionGSC and combined GSC-NRT treatments were equally effective in abstinence rate. Moreover Daily cigarette and the FEV1/FVC act/pred in GSC group was more than two other groups, indicating the health professionals can apply GSC alone in smoking cessation and improve lung function of COPD smokers.