The hyperkalemia that commonly occurs in patients hospitalized for acute heart failure does not affect outcomes, but it can lead to treatment changes that can in turn raise the risk of mortality.
That’s according to an analysis of data from 1,589 patients in the PROTECT trial (Placebo-Controlled Randomized Study of the Selective A1 Adenosine Receptor Antagonist Rolofylline for Patients Hospitalized with Acute Decompensated Heart Failure and Volume Overload to Assess Treatment Effect on Congestion and Renal Function) (N Engl J Med. 2010;363:1419-28).
In PROTECT, patients with acute heart failure and mild or moderate renal impairment (estimated creatinine clearance of 20-80 mL/min) were enrolled and randomized to receive placebo or rolofylline, a selective A1 adenosine receptor antagonist that is no longer in development. Because of the meticulous recording of potassium levels in PROTECT, investigators led by Joost C. Beusekamp of the University of Groningen, the Netherlands, used the data to examine the relations between incident hyperkalemia and changes in treatment, focusing on mineralocorticoid antagonists (MRAs).
They found that of the 35% of the patients who developed hyperkalemia at least once during hospitalization, defined as at least one episode of potassium above 5.0 mEq/L, 53% had been taking MRAs before hospitalization. And of those patients who been taking MRAs before hospitalization, 35% and 44% developed incident hypokalemia and had “a normal potassium” level, respectively. The hyperkalemia patients were also more likely to have their MRAs down-titrated (15%) during their stay than were those with low (8%) and normal (9%) potassium levels.
No significant association was found between in-hospital potassium levels and 180-day mortality or a composite of rehospitalization for cardiovascular or renal causes or all-cause death at 30 days (data not provided). However, there was a significant link between MRA dose reductions and 180-day mortality in a multivariate analysis (HR, 1.73; 95% confidence interval, 1.15-2.60; P = 0.008).
“Incident hyperkalemia was strongly associated with down-titration of MRA therapy which was, in turn, associated with a worse prognosis,” the investigators concluded.
SOURCE: J Am Coll Cardiol HF. 2019 Oct 9. doi: 10.1016/j.jchf.2019.07.010.