A composite inflammation–nutrition–coagulation score and 1-year mortality in geriatric proximal femur fractures: a retrospective cohort study

INTRODUCTION: This study aimed to evaluate the prognostic value of a composite score integrating the neutrophil-to-lymphocyte ratio (NLR), serum albumin, and D-dimer levels for predicting 1-year mortality in geriatric patients with proximal femur fractures. MATERIALS AND METHODS: This retrospective cohort study included 300 patients aged ≥ 65 years who were admitted with proximal femur fractures and underwent surgical treatment between November 2023 and March 2026. Demographic, clinical, and laboratory data were collected from hospital records. A composite score based on NLR, albumin, and D-dimer was calculated. An exploratory unweighted 0-3 composite score was constructed from cohort-derived ROC thresholds for NLR, albumin, and D-dimer. Logistic regression, receiver operating characteristic (ROC) curve analysis, net reclassification improvement (NRI), integrated discrimination improvement (IDI), Kaplan-Meier survival analysis, Cox regression, calibration analysis, and decision curve analysis (DCA) were performed to evaluate predictive performance. RESULTS: A total of 300 patients were analyzed, of whom 75 (25.0%) died within 1 year. Non-survivors were older and had significantly higher NLR and D-dimer levels and lower albumin levels (all p < 0.001). In mutually exclusive adjusted regression models, higher NLR and D-dimer levels, lower albumin levels, and a higher composite score were associated with 1-year mortality. In the composite-score model, each 1-point increase in score was associated with mortality after adjustment for clinical covariates (adjusted OR: 2.82, 95% CI: 1.95-4.08; p < 0.001). The composite score and its constituent biomarkers were not entered simultaneously into the same multivariable model. The composite score showed an apparent AUC of 0.86 (95% CI: 0.81-0.90), compared with AUCs of 0.74, 0.76, and 0.78 for NLR, albumin, and D-dimer, respectively. Addition of the score to the basic clinical model yielded a category-free NRI of 0.27 (95% CI: 0.14-0.40; p < 0.001) and an IDI of 0.068 (95% CI: 0.035-0.101; p < 0.001), indicating improved apparent risk separation within the derivation cohort. Kaplan-Meier and Cox regression analyses showed a stepwise increase in mortality risk across score groups (HR: 3.12 for high-risk group, p < 0.001). Calibration and decision-curve analyses suggested favorable apparent model performance and potential net benefit within the present study cohort. CONCLUSIONS: In this retrospective single-center cohort, the composite score integrating NLR, albumin, and D-dimer was associated with 1-year mortality and showed promising apparent discriminatory performance. The score should be considered an exploratory prognostic tool that may complement comprehensive clinical assessment and support future risk-stratification research. Prospective multicenter studies with external validation and evaluation of clinical impact are required before its use in routine practice can be considered.