Effect of Patiromer or Sodium Zirconium Cyclosilicate on Serum Potassium Concentrations in Patients With Acute Hyperkalemia: A Retrospective Cohort Study

Background: Acute hyperkalemia is a common, life-threatening electrolyte abnormality in hospitalized patients. Few studies exist on the role of potassium binders in acute hyperkalemia and none have compared patiromer and sodium zirconium cyclosilicate (SZC) head-to-head. Study Question: Is single-dose patiromer noninferior to single-dose SZC in acutely lowering serum potassium within 2–8 hours along with standard-of-care hyperkalemia therapies? Study Design: A retrospective cohort study included 156 patients with acute hyperkalemia hospitalized or present in the institution's emergency department who received either patiromer or SZC as a part of the acute hyperkalemia pathway. Measures and Outcomes: The primary outcome was the difference in serum potassium level from baseline to first recheck within 2–8 hours between single-dose patiromer and single-dose SZC. The noninferiority margin for the primary outcome was determined to be a 0.5 mEq/L difference in serum potassium. Results: The mean pretreatment potassium was 6.1 mEq/L in the patiromer group and 6.2 mEq/L in the SZC group. The only statistically significant difference found between groups was the presence of heart failure, which was higher in the patiromer group. The patiromer group was found to be noninferior to the SZC group for change in serum potassium between 2 and 8 hours (mean change difference 0.2 [95% CI, ∞ to −0.148]; P < 0.0001). Conclusions: SZC and patiromer were noninferior for the treatment of acute hyperkalemia. Clinicians may prefer to choose between these agents based on patient-specific factors such as cost, comorbidities, sodium restrictions, and ease of administration.