Hospitalization and Emergency Department Costs in Patiromer and Sodium Zirconium Cyclosilicate Users

BACKGROUND: A prior study using US electronic health records (EHR) directly compared the risk of heart failure- or edema-related hospitalizations, and edema-related emergency department (ED) visits for hyperkalemic patients using patiromer or sodium zirconium cyclosilicate. Incidence rates for all three clinical outcomes favored patiromer, but the prior study did not capture costs. METHODS: The current investigation combines the patiromer and sodium zirconium cyclosilicate cohort heart failure hospitalization and edema event rates from the prior study with mean event and prescription costs from 2019-2021 Optum Clinformatics data. The resulting heart failure and edema-related event and medication costs were then compared between patiromer and sodium zirconium cyclosilicate cohorts. We inflation-adjusted those to 2024 US dollars. RESULTS: For patiromer, costs for heart failure hospitalizations, edema hospitalizations, and edema ED visits were $30,269.05, $2,520.13, and $31.67 per person-year, respectively. For sodium zirconium cyclosilicate, costs for heart failure hospitalizations, edema hospitalizations, and edema ED visits were $39,478.29, $4,061.48, and $51.04, respectively. Medication costs per person-year were $11,423.68 and $8,561.71 for patiromer and sodium zirconium cyclosilicate, respectively. The aggregated cost savings with patiromer was $7,907.99 per person-year (95% CI $5,453.58 to $10,362.40) for all heart failure hospitalization and edema hospitalization and ED events, adjusted for both inflation and medication costs. CONCLUSIONS: Total event and medication costs were $44,245 in the patiromer cohort and $52,153 in the sodium zirconium cyclosilicate cohort. The $7,908 difference represents a 15% (95% CI 10% to 20%) cost savings associated with patiromer from all events, including medication costs and adjusted for inflation.