Preoperative geriatric nutritional risk index predicts prognosis and postoperative complications in elderly patients undergoing non-cardiac surgery: a retrospective cohort study

BackgroundLittle evidence on the association between geriatric nutritional risk index (GNRI) with prognosis and postoperative complications was observed. This study examined the potential prognostic value of GNRI in elderly patients undergoing non-cardiac surgery. MethodsThis retrospective analysis was data retried from the Chinese elderly patients' perioperative database (CEPPD), a multicenter registry, from June 1st, 2012 to August 15th, 2019. Patients were categorized into at-risk group (GNRI <= 98) and no-risk group (GNRI > 98). Kaplan-Meier analysis and multivariate Cox proportional hazard regression were used to explore the association between GNRI and overall survival (OS). Multivariate logistic regression and linear regression were used to explore the association of the GNRI with postoperative complications. A propensity score matching (PSM) analysis was also conducted at a 1:1 ratio using the greedy nearest-neighbor method. ResultsThe final analysis included 28,762 elderly patients undergoing non-cardiac surgery. The PSM cohort included 7,063 patients in each group. The 1-year OS rate was 90.2% in the at-risk group vs. 96.3% in the no-risk group (P < 0.001). In Kaplan-Meier analysis, OS was significantly shorter in the at-risk group (P < 0.001 for both before matching and PSM). In multivariable Cox regression, at-risk GNRI was independently associated with OS in both the overall analysis (HR: 1.682; 95% CI: 1.502-1.882; P < 0.001) and the PSM cohort (HR: 1.501; 95% CI: 1.316-1.711; P < 0.001). At-risk GNRI was also independently associated with postoperative heart injury, acute renal injury, pulmonary infection, surgical site infection, intensive care unit (ICU) admission, longer ICU length of stay (LOS), and longer postoperative LOS. ConclusionsPreoperative at-risk GNRI was associated with poor survival outcome and higher risk of postoperative complications in elderly patients undergoing non-cardiac surgery.