Albuminuria and Acute Heart Failure: A New Biomarker for Congestion and Follow-Up?

This study evaluated the trajectory of the urine albumin-to-creatinine ratio (UACR) in patients hospitalized with acute heart failure (HF) from pre-admission (baseline), through hospital admission, discharge and 2 weeks post-discharge. We also assessed its association with congestion-related biomarkers, including N-terminal pro-B-type natriuretic peptide (NT-proBNP), CA 125, and the neutrophil-to-lymphocyte (N/L) ratio.

Prospective, observational study including 99 consecutive patients admitted with acute HF. Blood and urine analyses were performed at admission, at discharge and 2 weeks post-discharge. Patients were stratified according to UACR at admission and the trajectories of UACR and biomarkers were evaluated. The clinical, analytical, and echocardiographic predictors of UACR were analysed.

Mean age was 70.8 ± 12.2 years, 57% were men. At admission, albuminuria was present in 65.7% of patients (45.5% microalbuminuria, 20.2% macroalbuminuria, respectively). A higher UACR at admission was associated with diabetes, lower eGFR, previous HF admission, higher clinical congestion score, mixed or right-sided congestive phenotype, higher NT-proBNP, and CA 125 levels. The UACR worsened from baseline to admission and improved at discharge, reflecting the congestion dynamics. NT-proBNP, CA 125, and N/L ratio showed similar patterns. Independent predictors of higher UACR at admission were diabetes, reduced renal function, higher aspartate aminotransferase (AST) and lower vitamin D levels. In the mixed linear regression analysis, lower eGFR, and higher AST levels remained independently associated with UACR trajectory. Admission UACR correlated with congestion score and predicted higher in-hospital mortality and early HF readmissions (<30 days).

Albuminuria is common in acute HF and exhibits a dynamic change in relation to congestion. These findings suggest a potential role as a biomarker for congestion monitoring. However, given the study limitations, the results should be considered exploratory and warrant confirmation in larger prospective studies.