Serum potassium dynamics during acute heart failure hospitalization

BACKGROUND: Available information about prognostic implications of potassium levels alteration in the setting of acute heart failure (AHF) is scarce. OBJECTIVES: We aim to describe the prevalence of dyskalemia (hypo or hyperkalemia), its dynamic changes during AHF-hospitalization, and its long-term clinical impact after hospitalization. METHODS: We analyzed 1779 patients hospitalized with AHF who were included in the REDINSCOR II registry. Patients were classified in three groups, according to potassium levels both on admission and discharge: hypokalemia (potassium5mEq/L). RESULTS: The prevalence of hypokalemia and hyperkalemia on admission was 8.2 and 4.6%, respectively, and 6.4 and 2.7% at discharge. Hyperkalemia on admission was associated with higher in-hospital mortality (OR=2.32 [95% CI: 1.04-5.21] p=0.045). Among patients with hypokalemia on admission, 79% had normalized potassium levels at discharge. In the case of patients with hyperkalemia on admission, 89% normalized kalemia before discharge. In multivariate Cox regression, dyskalemia was associated with higher 12-month mortality, (HR=1.48 [95% CI, 1.12-1.96], p=0.005). Among all patterns of dyskalemia persistent hypokalemia (HR=3.17 [95% CI: 1.71-5.88]; p