Identifying clinical instability in chronic heart failure: the role of microalbuminuria
P Bernardes, S Goncalves, J Quintal, T Duarte, M Madeira, A Sousa, C Ferreira, S Senhorinho, A Soares, D Ferreira, C Pohle, M Tomaz, D Campos, F SeixoAbstract
Background
Microalbuminuria (MA) reflects endothelial dysfunction and renal congestion — mechanisms closely linked to heart failure (HF) progression. Its role as a marker of recurrent decompensations in contemporary outpatient management remains uncertain.
Purpose
This study aimed to evaluate whether MA predicts HF events and mortality in a real-world same-day HF clinic cohort.
Methods
We retrospectively analysed 114 patients with chronic HF followed in a same-day HF clinic between January 2020 and December 2024. MA was defined as a urine albumin-to-creatinine ratio (UACR) ≥30 mg/g assessed in spot urine samples. MA was assessed opportunistically during clinically stable outpatient visits, a median of 5 months after inclusion (IQR 2–9). Median follow-up was 21 months (IQR 12–31). The primary endpoint was the total number of HF events, defined as unplanned visits or HF-related hospitalisations, during follow-up. Secondary endpoints included all-cause mortality. Associations were analysed using non-parametric tests and multivariable Poisson regression adjusted for age, sex, left ventricular ejection fraction (LVEF), diabetes, hypertension, and estimated glomerular filtration rate (eGFR).
Results
The cohort had a mean age of 71 ± 9.8 years, and 61% were male. MA was present in 39% of patients. Patients with MA had lower eGFR (49 ± 13 vs. 56 ± 14 mL/min/1.73 m²; p = 0.012) and higher NT-proBNP levels (median 3288 [1100–5483] vs. 2881 [1048–4700] pg/mL; p = 0.002) compared with those without MA. Patients with MA more frequently experienced at least one HF decompensation (78% vs. 58%, p = 0.029) and accumulated a higher total number of unplanned visits or hospitalisations (p = 0.016). In multivariable Poisson regression, MA remained an independent predictor of the composite endpoint (IRR = 1.39, 95% CI 1.01–1.92; p = 0.042), whereas age, sex, LVEF, diabetes, hypertension, and eGFR were not significant predictors. All-cause mortality was low (9.6%) and did not differ between groups (11.1% vs. 8.7%, p = 0.669).
Conclusion
In this real-world HF clinic cohort, microalbuminuria was independently associated with a higher incidence of unplanned visits and hospitalisations, identifying patients at increased risk of recurrent decompensations. MA may represent a simple, low-cost biomarker of clinical instability in ambulatory heart failure management.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.