Inflammatory and Metabolic Biomarkers Associated with In-Hospital Mortality in Patients Hospitalized with Heart...

Background/Objectives: Inflammatory and metabolic abnormalities are common in patients hospitalized with heart failure (HF), particularly during episodes of decompensation. Their associations with short-term in-hospital outcomes remain incompletely understood. Methods: We retrospectively reviewed 499 patients with documented chronic HF who were admitted for acute medical conditions between January and May 2024. The cohort was not limited to patients admitted for HF exacerbation; patients were classified as having compensated or decompensated HF at admission. Body mass index (BMI) was available for 498 patients, whereas HF status at admission was available for all 499 patients. Clinical, metabolic, and laboratory parameters were analyzed, with particular attention to C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Patients were stratified according to BMI category (<25 kg/m² or ≥25 kg/m²) and HF status at admission. Associations with all-cause in-hospital mortality were evaluated using multivariable logistic regression analysis. Results: Patients with decompensated HF at admission had higher CRP, NLR, PLR, SII, and NT-proBNP levels, as well as lower hemoglobin and eGFR values. All-cause in-hospital mortality was numerically higher in patients with BMI < 25 kg/m² than in those with BMI ≥ 25 kg/m² (8.4% vs. 4.2%), but the difference was not statistically significant (Pearson's χ² test, p = 0.063). In adjusted analyses, CRP and SII were associated with all-cause in-hospital mortality, whereas NT-proBNP was not. Patients with higher BMI more often had glycemic and lipid abnormalities, whereas those with lower BMI had a more pronounced inflammatory profile. The apparent area under the curve (AUC) values were 0.793 for the CRP-based model and 0.814 for the SII-based model; after bootstrap correction, the optimism-corrected AUC values were 0.729 and 0.754, respectively. Conclusions: Higher CRP and SII levels were associated with all-cause in-hospital mortality after adjustment for selected clinical variables.