Association between in-hospital changes in estimated plasma volume status and worsening renal function in patients with acute heart failure

Abstract

Worsening renal function (WRF) during treatment for acute heart failure (AHF) has context-dependent clinical implications. Estimated plasma volume status (ePVS), calculated from hematocrit and body weight, may complement decongestion assessment. We evaluated the association between in-hospital change in ePVS (ΔePVS) and WRF. This single-center retrospective study included 309 adults hospitalized with AHF from 2021 to 2025. ΔePVS was defined as the last in-hospital ePVS minus admission ePVS; WRF was defined as an increase in serum creatinine of ≥ 26.5 µmol/L or ≥ 50%. Analyses included multivariable regression, bootstrap correction, and a 48-hour landmark analysis. Readmission analyses treated death as a competing event. WRF occurred in 92 patients (29.8%). ΔePVS was higher in patients with WRF than in those without WRF (1.0% vs. − 4.5%; P < 0.001). The adjusted odds ratio per 5% increase in ΔePVS was 1.54 (95% confidence interval [CI], 1.19–1.99). In sequential Firth models of 295 patients, the odds ratio was 1.39 (95% CI, 1.05–1.84) after adjustment for treatment intensity and diuretic response; the corresponding 48-hour landmark estimate was 1.36 (95% CI, 1.04–1.78). ΔePVS correlated modestly with changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and clinical congestion signs and was driven mainly by hematocrit change. Adding ΔePVS increased the apparent area under the receiver operating characteristic curve (AUC) by 0.016 ( P = 0.098). The WRF/ΔePVS ≥ 0 phenotype had a greater 90-day readmission risk than the no-WRF/ΔePVS < 0 phenotype (subdistribution hazard ratio [sHR], 3.84; 95% CI, 1.91–7.72). A smaller decrease or an increase in ePVS was associated with WRF, less hemoconcentration, and a poorer early diuretic response. ΔePVS may complement multimodal decongestion assessment; however, its incremental discriminative and prognostic value requires external validation.