Optimal period of smoking cessation to reduce the incidence of postoperative pulmonary complications in lung cancer

OBJECTIVES: Postoperative pulmonary complications (PPCs) provoke an extended hospital stay and increased postoperative mortality. Although several factors can cause PPCs, smoking is the only factor that can be adjusted within a short period of time preoperatively. However, the optimal period of smoking cessation to reduce the risk of PPCs remains unclear. METHODS: A total of 1260 patients with primary lung cancer who underwent radical pulmonary resection between January 2010 and December 2021 were analysed retrospectively. RESULTS: We classified patients into 2 groups: non-smokers (patients who had never smoked) and smokers (patients who had ever smoked). The frequency of PPCs was 3.3% in non-smokers and 9.7% in smokers. PPCs were significantly less frequent in non-smokers than in smokers (P < 0.001). When smokers were classified according to the duration of smoking cessation, the frequency of PPCs was significantly lower for a duration of 6 weeks or more than for <6 weeks (P < 0.001). In a propensity score analysis performed for 6 or >6 and <6 weeks’ smoking cessation in smokers, the frequency of PPCs was significantly lower for smokers with 6 or more weeks’ smoking cessation than for smokers with <6 weeks’ smoking cessation (P = 0.002). A multivariable analysis identified <6 weeks’ smoking cessation as a significant predictor of PPCs for smokers (odds ratio: 4.55, P < 0.001). CONCLUSIONS: Smoking cessation for 6 or more weeks preoperatively significantly reduced the frequency of PPCs.