P4901Association between serum potassium and clinical outcomes in UK patients with heart failure

Abstract

Introduction: The association of adverse clinical outcomes with hypo- or hyperkalemia has been poorly characterized in heart failure (HF) patients in the UK. Purpose: To examine the association between serum potassium (K+) and major adverse cardiovascular events (MACE; arrhythmia, myocardial infarction, stroke, HF exacerbation) or mortality in a real-world cohort of HF patients in the UK. Methods: A retrospective study of UK patients with HF was conducted with primary care and hospital data from the linked Clinical Practice Research Datalink and Hospital Episode Statistics databases (1/1/2006-31/12/2015). Adult patients with a first record of HF during the study period (index date) were included. Patients were excluded if they had a prior history of HF, eGFR <3.5 and >=6.0 mEq/L (Figure). A similar but stronger association was observed between serum K+ and mortality (Figure). Compared with serum K+ of >=4.5-<5.0 (reference range), the adjusted IRR of mortality was 2.86 for serum K+ of <3.5 mEq/L, 1.55 for serum K+ >=5.5-<6.0 mEq/L and 3.54 for serum K+ >=6.0 mEq/L. Conclusion: In the real-world setting in the UK, risks of MACE and mortality are significantly increased in HF patients with serum K+ levels of <3.5 and >=6.0 mEq/L, suggesting clinicians should closely monitor and manage K+ abnormalities among HF patients. Further research is needed to assess the causal relationship between serum K+ and clinical outcomes.