Hyperkalemia, Worsening Renal Function, Acute Kidney Injury and Clinical Outcomes in Acute Heart Failure

Background Kidney dysfunction and hyperkalemia are commonly observed in heart failure (HF). Their relationship has not been fully investigated in acute HF (AHF), especially in relation to worsening renal function (WRF) and acute kidney injury (AKI). Purpose: We aimed to investigate the relationship between changes in potassium, WRF and AKI and its prognostic implication in AHF. Methods We retrospectively analyzed the AKINESIS, which is a multicenter, prospective cohort study of AHF patients. Levels of serum potassium and creatinine were recorded each day during hospitalization. Urine neutrophil gelatinase-associated lipocalin (NGAL) was measured at admission, 4-hour, day 1, 2, 3 and discharge. Patients were classified into 3 groups; hyperkalemia (> 5mEq/l) on admission, an increasing trend (≤ 5 mEq/l on admission and increased to > 5mEq/l during hospitalization) and non-hyperkalemia (≤ 5 mEq/l during hospitalization). WRF was defined as an increase of ≥ 0.3 mg/dl or ≥ 50% in creatinine. Clinical outcome was one-year mortality. Results Among 912 patients analyzed, hyperkalemia on admission and an increasing trend were observed in 10% and 7.8%, respectively. The incidence of WRF in patients with hyperkalemia on admission, an increasing trend and non-hyperkalemia were 41%, 59% and 27%, respectively (p Conclusions Hyperkalemia was associated with WRF and AKI in AHF. An increase in potassium during hospitalization but not a higher level on admission was associated with poor prognosis independent of WRF and AKI.