Smoking cessation before coronary artery bypass grafting improves operative outcomes

Background: The detrimental effect of active smoking on operative outcome after coronary artery bypass grafting (CABG) is still debated and smoking cessation programs are usually deferred until after surgery. The potential benefit from smoking cessation on postoperative outcomes is investigated in this study. Methods: A retrospective analysis on a large cohort of patients who underwent CABG at a single institution was performed. Generalized boosted regression modeling was used to estimate the multinominal propensity scores for smoking status categories and the average treatment effect on the treated was calculated for all outcomes of interest. Results: A total of 6113 patients who underwent isolated CABG for the first time were included. At baseline, there were 640 (10.4%) current smokers, 3309 (54.1%) ex-smokers, and 2164 (35.3%) nonsmokers. Multilevel propensity score weighted analysis showed a beneficial effect of smoking cessation compared with current smoking, which increased the risk for all major pulmonary complications (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.13-2.10; P=.006), including reintubation (OR, 1.95; 95% CI, 1.17-3.25; P=.01), full tracheostomy (OR, 3.04; 95% CI, 1.49-6.18; P=.002), lung infection/consolidation (OR, 1.44; 95% CI, 1.02-2.02; P=.03). Although smoking cessation did not significantly improve other outcomes, it was associated with a nonsignificant trend toward a decreased risk for in-hospital mortality (OR, 1.83; 95% CI, 0.85-3.91; P=.1). Conclusions: This study showed that smoking cessation before CABG reduced the risk of serious pulmonary complications. The present findings indicate that embarking on a smoking cessation program should not be deferred until after surgery.