Impaired renal function and mortalities in acute heart failure with different phenotypes

Impaired renal function (IRF) prevails in patients with acute heart failure. The study aimed to investigate the prevalence of on-admission IRF and its association with short-term and long-term mortalities in patients hospitalized for HF with reduced (HFrEF), mildly reduced (HFmrEF), and preserved (HFpEF) left ventricular ejection fraction (LVEF).

Patients hospitalized for acute heart failure were enrolled and stratified by LVEF into three phenotypes as HFpEF (≥50%), HFmrEF (40-49%), and HFrEF (<40%). IRF was defined as an estimated glomerular filtration rate of ≤60 mL/min/1.73m² on admission. National Death Registry was linked for the identification of mortality.

Of 2613 patients enrolled, 673 (25.7%) had HFrEF, 367 (14.0%) had HFmrEF, and 1573 (60.1%) had HFpEF, whereas IRF was prevalent among 63.7, 68.6, and 67.5% of them, respectively. IRF significantly correlated with higher long-term mortality in each phenotype of HF. However, IRF was associated with 90-day and 1-year mortality in subjects with HFrEF and HFmrEF, but not HFpEF. After accounting for age, gender, hypertension, diabetes, coronary artery disease, atrial fibrillation, stroke, serum sodium, de novo heart failure, date of enrolment, and systolic blood pressure <90 mmHg or use of inotropic agents, IRF remained related to 5-year mortality in patients with HFrEF (hazard ratio and 95% confidence interval: 1.346, 1.034-1.751), HFmrEF (2.210, 1.435-3.404), and HFpEF (1.493, 1.237-1.801).

On-admission IRF was independently predictive of long-term mortality in patients hospitalized for HF, irrespective of HF phenotypes. Furthermore, IRF was also associated with short-term mortality in HFrEF and HFmrEF, but not in HFpEF.