The Impact of the Geriatric Nutritional Risk Index on Postoperative Cognitive Dysfunction and Complications after Total Hip Arthroplasty Under General Anesthesia: A Retrospective Study

The Geriatric Nutritional Risk Index (GNRI) is widely used to assess nutritional status. However, its association with postoperative cognitive dysfunction (POCD) and postoperative complications in elderly patients receiving total hip arthroplasty remains inadequately explored. GNRI was calculated based on serum albumin and body weight. POCD was diagnosed using the Z-score method based on cognitive test performance on the seventh postoperative day. Glial fibrillary acidic protein (GFAP) and S100β levels were determined using an enzyme-linked immunosorbent assay. A Receiver Operating Characteristic curve was performed to evaluate the predictive value of GNRI. Multivariate logistic regression was conducted to identify risk factors for POCD in elderly patients undergoing total hip arthroplasty. The POCD group was significantly older, had lower educational attainment, longer surgery duration, greater intraoperative blood loss, and lower preoperative GNRI scores compared to the non-POCD group. Preoperative GNRI demonstrated moderate predictive value for POCD, with an area under curve (AUC) of 0.78. Multivariate logistic regression analysis identified age (odds ratio [OR]: 1.214, 95% confidence interval [CI]: 1.047-1.449), blood loss (OR: 1.198, 95% CI: 1.055-1.493), and anesthesia duration (OR: 1.376, 95% CI: 1.112-1.795) as significant risk factors for POCD, while preoperative GNRI (OR: 0.885, 95% CI: 0.768-0.973) was identified as a protective factor. POCD patients exhibited significantly lower Montreal Cognitive Assessment (MoCA) scores and higher serum S100β and GFAP levels than the non-POCD group. Preoperative GNRI was positively correlated with MoCA scores (r = 0.46, <i>p</i> < 0.001) and negatively correlated with serum S100β (r = -0.43, <i>p</i> < 0.001) and GFAP (r = -0.37, <i>p</i> < 0.001) levels. Higher preoperative GNRI scores were associated with a reduced incidence of postoperative complications, including pulmonary infections and liver dysfunction. Preoperative GNRI serves as an effective predictor of POCD and postoperative complications in elderly patients receiving hip arthroplasty.