The value of lactate-to-albumin ratio in predicting fatigue and in-hospital mortality in patients with heart failure: A retrospective study

BACKGROUND: The lactate-to-albumin ratio (LAR), integrating hypoperfusion and inflammation, is a novel prognostic marker in heart failure (HF), but its prognostic value for both mortality and fatigue remains underexplored. OBJECTIVES: This study aimed to evaluate the predictive value of LAR for in-hospital mortality and patient-reported fatigue in HF. METHODS: This single-center retrospective study enrolled 536 patients with acute HF. LAR was calculated from admission lactate and albumin. The primary outcome was in-hospital all-cause mortality. Fatigue was assessed using the Multidimensional Fatigue Inventory-20 (MFI-20) scale. Multivariate logistic regression was used to adjust for confounders, with restricted cubic splines and receiver operating characteristic (ROC) curve analyses employed. RESULTS: Among 536 patients, 144 (26.9 %) died. LAR was significantly higher in non-survivors than in survivors (median 0.16 vs. 0.05, P < 0.001). After multivariable adjustment, each 0.01-unit increase in LAR was independently associated with a 23 % higher odds of in-hospital mortality (OR 1.23, 95 % CI: 1.05-1.44, P = 0.012). A significant dose-response relationship was identified between higher LAR and increased fatigue severity (P = 0.025). ROC analysis demonstrated superior discriminative power of LAR (AUC = 0.74) compared to lactate (AUC = 0.65) or albumin (AUC = 0.61) alone. CONCLUSIONS: Admission LAR is a strong, independent predictor of in-hospital mortality and is positively associated with fatigue severity in HF. Its superior performance over single biomarkers underscores its clinical utility for early risk stratification.