Modified Frailty Index Independently Predicts Postoperative Pulmonary Infection in Elderly Patients Undergoing Radical Gastrectomy for Gastric Cancer

BACKGROUND: Pulmonary infection is one of the most common postoperative complications after radical gastrectomy for gastric cancer (GC) and is associated with a poorer prognosis. This study aimed to investigate potential predictive factors for pulmonary infection in elderly GC patients. METHODS: This study retrospectively enrolled 346 elderly GC patients undergoing elective radical gastrectomy between January 2017 and December 2020. Pulmonary infection within postoperative 30 days was set as the primary observational endpoint. The baseline demographic, clinicopathological, and laboratory data were compared between patients with or without pulmonary infection. ROC curves were plotted to evaluate the cut-off and predictive values of factors. Binary univariate and multivariate logistic regression analyses were employed to determine risk factors for postoperative pulmonary infection. RESULTS: Of the enrolled 346 patients, pulmonary infection was observed in 51 patients within postoperative 30 days, with an incidence of 14.7%. mFI was a significant predictor for pulmonary infection by ROC curve analysis (AUC: 0.770, P < 0.001). Moreover, preoperative mFI was the only independent risk factor for pulmonary infection (OR: 2.72, 95% CI: 2.02–3.31, P = 0.011) by univariate and multivariate logistic regression analyses. CONCLUSION: Our study indicates that mFI independently predicts pulmonary infection in elderly GC patients.