Association between prognostic nutritional index and risk of moderate-to-severe basic activities of daily living dependence two years after hip fracture surgery in older adults.

Background: Hip fractures are a common and serious health concern in older adults. The ability to perform basic activities of daily living (BADL) is a key indicator of long-term functional status. This study aimed to evaluate the prognostic value of the Prognostic Nutritional Index (PNI) in identifying older patients at risk of moderate-to-severe BADL dependence two years after hip fracture surgery.

Methods: A total of 526 older patients with hip fractures were included in the analysis. Baseline characteristics and preoperative indicators were systematically examined. Univariate and multivariate logistic regression models were applied to identify independent factors associated with moderate-to-severe BADL dependence. Restricted cubic spline (RCS) analysis was used to explore potential nonlinear relationships, while receiver operating characteristic (ROC) curves evaluated the discriminatory performance of PNI. Subgroup analysis was performed to explore population differences. Propensity score matching (PSM) was performed to enhance robustness and control for confounding factors.

Results: The median age of the cohort was 73.0 years (interquartile range: 67.0-79.0), and 69.96% of participants were female. A total of 43 patients (8.17%) exhibited moderate-to-severe BADL dependence at two years postoperatively. Multivariate logistic regression revealed that higher preoperative PNI was independently associated with a lower risk of long-term dependence (OR: 0.90; 95% CI:0.82-0.99; P = 0.026). ROC analysis demonstrated a moderate discriminatory ability (AUC = 0.659), and RCS analysis indicated a linear relationship between PNI and BADL dependence (P-nonlinearity = 0.674). The association remained robust after PSM.

Conclusion: Preoperative PNI is an independent predictor of long-term functional dependence in older patients undergoing hip fracture surgery. These findings underscore the importance of nutritional assessment and optimization in preoperative care to improve postoperative functional outcomes in this vulnerable population.