Abstract 17379: The Incidence and Risk Associated with a Serum Potassium <4.0 Mmol/l in Patients with Heart Failure and a Reduced Left Ventricular Ejection Fraction (HF-REF): Results from the Emphasis-HF Trial
Introduction and Methods: Hypokalemia, defined as a serum potassium (K+) <3.5 mmol/l, is recognized as an important risk factor for cardiovascular death (CVD) in patients with HF-REF. The incidence of K+ <4.0 mmol/l and any associated risk is less certain. We analyzed the results of the EMPHASIS-HF trial in patients (n=2737) with HF-REF and mild symptoms, randomized to placebo or eplerenone with regard to the incidence of a K+ <4.0 mmol/l and the risk of the primary endpoint of CVD or hospitalization for heart failure (HFH) during the randomized trial with a median follow up of 21 months.
Results: At baseline, 536/2737 (19.6%) patients had a K+ <4.0 mmol/L and 2201 (80.4%) a K+ ≥4.0 mmol/L. During treatment, 393 (73.3%) of the former and 774 (35.2%) of the latter had a K+ <4.0 mmol/L (P<0.001). At baseline, 268/1364 (19.7%) eplerenone-treated and 268/1373 (19.5%) placebo-treated patients had a K+ <4.0 mmol/L (P=0.932). During treatment, these proportions were 519/1364 (38.1%) and 648/1373 (47.2%), respectively (P<0.0001). Of patients with a baseline K+ <4.0 mmol/L, 79/536 (14.7%) patients experienced CVD (and 132/536 [24.6%] CVD/HFH). Among patients with a K+ ≥4.0 mmol/L, these proportions were 253/2201 (11.5%) [P=0.039] and 473/2201 (21.5%) [P=0.117]. The risk associated with a K+ <4.0 mmol/l at baseline and during treatment based on Cox’s analysis is shown in the Table 1.
Conclusion: A K+ <4.0 mmol/l was relatively frequent at baseline in patients with HF-REF and mild symptoms and was associated with an increased risk of developing a K+<4.0 mmol/l and CVD during treatment. Eplerenone significantly reduced the incidence of K+ <4.0 mmol /l, and consistently reduced the risk of CVD/HFH regardless of the patient’s K+ profile in the study.
- © 2012 by American Heart Association, Inc.