Smoking and timing of cessation on postoperative pulmonary complications after curative-intent lung cancer surgery

Background: Smoking is a risk factor for postoperative pulmonary complications (PPC) following non-small cell lung cancer (NSCLC) surgery. The optimal timing for preoperative smoking cessation has not been identified. Our study aimed to observe the impact of preoperative smoking cessation on PPC incidence and other postoperative outcomes including long-term survival. Methods: A prospective study included consecutive patients following resection for NSCLC in a regional thoracic centre over a 4-year period (2010-2014). Patients were stratified according to self-reported preoperative smoking status. The primary endpoint was PPC incidence, which was assessed from postoperative day one onwards using the Melbourne Group Scale. Secondary endpoints included short-term outcomes (hospital length of stay [LOS], intensive therapy unit [ITU] admission, 30-day hospital readmission rate) and long-term survival. Results: Four hundred and sixty-two patients included 111 (24%) current smokers, 55 (12%) ex-smokers <6 weeks, 245 (53%) ex-smokers >= 6 weeks and 51 (11%) never smokers. PPC occurred in 60 (13%) patients in total. Compared to never smokers, current smokers had a higher frequency of PPC (22% vs. 2%, p = 0.004), higher frequency of ITU admission (14% vs. 0%; p = 0.001) and a longer median (IQR) hospital LOS (6 [5] vs. 5 [2]; p = 0.001). In the ex-smokers there was a trend for a lower frequency of PPC (<6 weeks, 10.9% vs. = 6 weeks, 11.8%) and ITU admission (<6 weeks, 5.5% vs. = 6 weeks, 4. 5%), but there was no difference between the <6 weeks or = 6 weeks ex-smoking groups prior to surgery. There was no significant difference in long-term survival found between the groups of differing smoking status (median follow-up 29.8 months, 95% CI 28.4-31.1). Conclusion: Current smokers have higher postoperative morbidity; this risk reduces following smoking cessation but 6 weeks does not appear to identify a time-point where differences in outcomes are noted.