Risk factors for postoperative pneumonia and prognosis in lung cancer patients after surgery: A retrospective study

Postoperative pneumonia (POP) is one of the most frequent complications following lung surgery. The aim of this study was to identify the risk factors for developing POP and the prognostic factors in lung cancer patients after lung resection. We performed a retrospective review of 726 patients who underwent surgery for stages I–III lung cancer at a single institution between August 2017 and July 2018 by conducting logistic regression analysis of the risk factors for POP. The Cox risk model was used to analyze the factors influencing the survival of patients with lung cancer. We identified 112 patients with POP. Important risk factors for POP included smoking (odds ratio [OR], 2.672; 95% confidence interval [CI], 1.586–4.503; P < .001), diffusing capacity for carbon monoxide (DLCO) (40–59 vs ≥80%, 4.328; 95% CI, 1.976–9.481; P < .001, <40 vs ≥80%, 4.725; 95% CI, 1.352–16.514; P = .015), and the acute physiology and chronic health evaluation (APACHE) II score (OR, 2.304; 95% CI, 1.382–3.842; P = .001). In the Cox risk model, we observed that age (hazard ratios (HR), 1.633; 95% CI, 1.062–2.513; P = .026), smoking (HR, 1.670; 95% CI, 1.027–2.716; P = .039), POP (HR, 1.637; 95% CI, 1.030–2.600; P = .037), etc were predictor variables for patient survival among the factors examined in this study. The risk factors for POP and the predictive factors affecting overall survival (OS) should be taken into account for effective management of patients with lung cancer undergoing surgery.