Longitudinal changes in renal function after acute heart failure according to worsening renal function and...

Worsening renal function (WRF) in acute heart failure (AHF) has been associated with poor outcomes; however, when accompanied by hemoconcentration, WRF is not necessarily associated with adverse outcomes. The associations of WRF and hemoconcentration with renal outcomes and longitudinal changes in renal function remain unclear.

In this multicenter retrospective study, 2556 hospitalized patients with AHF (median 80 years; 60% male) were categorized into four groups according to WRF and hemoconcentration status. WRF was defined as a ≥20% decrease in estimated glomerular filtration rate (eGFR) from admission to discharge. Hemoconcentration was defined as concurrent increases in hemoglobin and hematocrit levels from admission to discharge. The primary outcome was a composite of initiation of maintenance dialysis, decline in eGFR to <10 mL/min/1.73 m², or ≥40% reduction in eGFR within one year after discharge.

The WRF/hemoconcentration group had less frequent inotrope use and lower N-terminal pro-B-type natriuretic peptide levels at discharge. The cumulative incidence of the primary outcome was 18.4%, 15.9%, and 20.0% in the No WRF/No hemoconcentration, No WRF/hemoconcentration, and WRF/No hemoconcentration groups, respectively, and was lowest at 9.5% in the WRF/Hemoconcentration group. In multivariable analysis, this group was significantly associated with a lower risk of the primary outcome, compared with the No WRF/No hemoconcentration group (subdistribution hazard ratio 0.58, 95% confidence interval 0.36 to 0.93, p = 0.025). The longitudinal changes in renal function differed significantly across the groups; the WRF/Hemoconcentration group showed an attenuated decline or even improvement in eGFR (+3.6 mL/min/1.73 m²/year), whereas the No WRF/No hemoconcentration group exhibited the steepest decline (-6.2 mL/min/1.73 m²/year).

Renal function changes after AHF hospitalization were heterogeneous, and WRF accompanied by hemoconcentration was associated with favorable renal outcomes within one year after discharge.