Malnutrition drives re-revision and mortality in elderly revision arthroplasty: the prognostic value of GNRI

BACKGROUND: The impact of perioperative malnutrition on long-term outcomes in elderly revision arthroplasty remains underexplored. This study aimed to (1) evaluate the association between preoperative GNRI and the risk of re-revision; and (2) assess its prognostic value for all-cause mortality. METHODS: A retrospective cohort of 771 patients aged ≥ 60 years undergoing hip or knee revision arthroplasty (2008–2024) was analyzed. GNRI was calculated preoperatively and assessed as both continuous and categorical variables. Primary outcomes were all-cause re-revision and all-cause mortality. Logistic regression, Cox models, restricted cubic splines, and ROC analysis were applied. RESULTS: Lower GNRI was independently associated with increased risks of re-revision (OR per unit decrease = 1.05; P = 0.005) and mortality (HR for GNRI < 101.21 = 2.14; P = 0.020). RCS showed nonlinear relationships, with inflection points around GNRI = 105. GNRI demonstrated moderate predictive performance for both outcomes (AUC: 0.68 for re-revision, 0.65 for mortality). CONCLUSIONS: Preoperative malnutrition, as measured by GNRI, predicts both re-revision and all-cause mortality in elderly revision arthroplasty patients. Nutritional risk stratification may help guide perioperative management. LEVEL OF EVIDENCE: Level III, prognostic study.