Serum Potassium Levels and Outcome in Acute Heart Failure (Data from the PROTECT and COACH Trials)

Jozine M. ter Maaten,Daniel M. Bloomfield,Jasper Tromp,John R. Teerlink,Beth Davison,Tiny Jaarsma,Gad Cotter,Martje H.L. van der Wal,Michael M. Givertz,Howard C. Dittrich,John G.F. Cleland,Hans L. Hillege,Adriaan A. Voors,Piotr Ponikowski,Christopher M. O'Connor,Dirk J. van Veldhuisen,Kevin Damman,Marco Metra,Peter van der Meer

doi:10.1016/j.amjcard.2016.09.038

Abstract

Serum potassium is routinely measured at admission for acute heart failure (AHF), but information on association with clinical variables and prognosis is limited. Potassium measurements at admission were available in 1,867 patients with AHF in the original cohort of 2,033 patients included in the Patients Hospitalized with acute heart failure and Volume Overload to Assess Treatment Effect on Congestion and Renal FuncTion trial. Patients were grouped according to low potassium (<3.5 mEq/l), normal potassium (3.5 to 5.0 mEq/l), and high potassium (>5.0 mEq/l) levels. Results were verified in a validation cohort of 1,023 patients. Mean age of patients was 71 ± 11years, and 66% were men. Low potassium was present in 115 patients (6%), normal potassium in 1,576 (84%), and high potassium in 176 (9%). Potassium levels increased during hospitalization (0.18 ± 0.69 mEq/l). Patients with high potassium more often used angiotensin-converting enzyme inhibitors and mineralocorticoid receptor antagonists before admission, had impaired baseline renal function and a better diuretic response (p= 0.005), independent of mineralocorticoid receptor antagonist usage. During 180-day follow-up, a total of 330 patients (18%) died. Potassium levels at admission showed a univariate linear association with mortality (hazard ratio [log] 2.36, 95% confidence interval 1.07 to 5.23; p= 0.034) but not after multivariate adjustment. Changes of potassium levels during hospitalization or potassium levels at discharge were not associated with outcome after multivariate analysis. Results in the validation cohort were similar to the index cohort. In conclusion, high potassium levels at admission are associated with an impaired renal function but a better diuretic response. Changes in potassium levels are common, and overall levels increase during hospitalization. In conclusion, potassium levels at admission or its change during hospitalization are not associated with mortality after multivariate adjustment.

Highlights

Serum potassium is routinely measured during hospitalization for acute heart failure (AHF), and heart failure (HF) guidelines recommend daily assessment of potassium during treatment with intravenous loop diuretics.[1]
Higher potassium levels at admission were associated with higher rates of diabetes, more previous usage of angiotensinconverting enzyme (ACE) inhibition and mineralocorticoid receptor antagonists (MRA), and a lower Estimated glomerular filtration rate (eGFR)
Diuretic response expressed as kilograms of weight loss per 40 mg of furosemide was lower for patients with low potassium from admission to day 4 after admission (p 1⁄4 0.005, Table 2)

Summary

Introduction

Serum potassium is routinely measured during hospitalization for acute heart failure (AHF), and heart failure (HF) guidelines recommend daily assessment of potassium during treatment with intravenous loop diuretics.[1]. Heart Failure/Serum Potassium Levels and Outcome in AHF investigated the association between serum potassium levels at admission, changes during hospitalization, and the association with clinical characteristics and mortality

Methods

Results

Conclusion