Tracking albuminuria in acute heart failure: a clue to long-term prognosis

Introduction

Albuminuria is a well-established risk factor for cardiovascular disease and heart failure (HF). Recently, the urine albumin/creatinine ratio (UACR) has emerged as a potencial marker of systemic congestion. However, the UACR trajectory during acute heart failure (AHF) and its prognostic relevance after discharge remain poorly understood.

Purpose

To assess how in-hospital UACR changes impact in long-term outcomes after admission for AHF.

Methods

Single center, prospective observational study included all patients with AHF admitted to the Cardiology Department between February - June 2024. Patients were classified based on UACR levels at admission and discharge: (1) normoalbuminuria at both time points; (2) microalbuminuria at admission with a >50% reduction or normalization at discharge; and (3) microalbuminuria at admission with <50% reduction or any episode of macroalbuminuria during hospitalization.

Results

A total of 91 patients were included: 30.8% in group 1 (n=28), 31.9% in group 2 (n=29) and 37.4% in group 3 (n=34). Median follow-up was similar across groups: 579 days (547–624), p=0.295. Patients in groups 2–3 had more comorbidities and worse prior UACR. No differences were found in HF etiology. Baseline treatment was similar, except for higher use of beta-blockers and SGLT2 inhibitors in groups 2–3. No significant differences in echocardiographic parameters were observed (Figure 1).

Patients in groups 2–3 had a higher proportion of prior HF admission, a longer duration of intravenous diuretic use, greater use of other diuretics and worse clinical congestion scores (CCS).

Laboratory data revealed a slight worsening of renal function, higher levels of biomarkers (NT-proBNP and CA 125), increased parathyroid hormone and lower vitamin D levels in groups 2–3. No differences were found in liver function. A significant reduction in UACR after decongestion was observed in all groups.

At discharge, treatment was similar between groups, except for a greater loop diuretic use in groups 2–3.

During follow-up, 28 patients (30.7%) were readmitted for HF and 12 patients (13.2%) died. Six deaths were due to HF, one in group 2 and five in group 3. Five patient need renal replacement therapy (four from group 3). Heart failure decompensation and global mortality were more frequent in groups 2 and 3. The composite endpoint of cardiovascular death or heart failure readmission occurred more frequently in group 3 (p=0.057).

Conclusions

In AHF admission, the UACR trajectory could represent a potential prognostic marker. Patients with persistent or worsening UACR (groups 2–3) tended to have a higher comorbidity burden, more severe clinical congestion, slightly worse biomarker profiles and a trend toward increased HF readmission and mortality during follow-up. These results support the hypothesis that UACR monitoring may contribute to risk stratification and potentially inform future therapeutic approaches in AHF management.Clinical characteristics between groupsFor image description, please refer to the figure legend and surrounding text.Kaplan–Meier curve by UACR groupsFor image description, please refer to the figure legend and surrounding text.