Predictive Value of IBI for In-Hospital Death in Elderly Patients with Non-ST-Segment Elevation Myocardial Infarction

BACKGROUND Non-ST-segment elevation myocardial infarction (NSTEMI) has a with high incidence rate and a high mortality rate in elderly patients, and inflammation plays an important role. As a useful inflammatory marker, the relationship between the inflammatory burden index (IBI) and in-hospital death of elderly patients with NSTEMI remains unclear. The aim of this study was to investigate the predictive value of IBI for in-hospital death in elderly patients with NSTEMI. MATERIAL AND METHODS This single-center study retrospectively enrolled patients diagnosed with NSTEMI between February 2021 and February 2025. All patients were ≥75 years old and did not receive percutaneous coronary intervention (PCI) treatment during hospitalization. Patients were divided into 2 groups according to whether cardiogenic death occurred during hospitalization. IBI was calculated as the product of C-reactive protein and the neutrophil-to-lymphocyte ratio. RESULTS This study enrolled a total of 418 patients, with a mean age of 79.60±3.67 years. During the hospitalization period, cardiogenic death occurred in 43 (10.3%) patients. After adjusting for possible confounding factors, multivariate logistic regression analysis showed that IBI (OR=2.22, 95% CI: 1.64-3.00) was an independent risk factor for in-hospital death in elderly patients with NSTEMI. Restricted cubic spline suggested a non-linear dose-response relationship between IBI and in-hospital death. The results of ROC showed that the area under the curve of IBI was 0.760. CONCLUSIONS In elderly patients with NSTEMI, IBI demonstrated an independent association with in-hospital mortality, with modest discriminatory performance. There is a non-linear dose-response relationship between IBI and in-hospital death in elderly patients with NSTEMI.