Heart Failure and Edema Costs in Patiromer and Sodium Zirconium Cyclosilicate Users

Background Previous work suggested differences between patients taking patiromer or sodium zirconium cyclosilicate (SZC) in real-world risk of heart failure (HF) hospitalizations and edema hospitalizations or emergency department (ED) visits (edema events). We further investigated these differences to assess economic importance. Retrospective study using published event rates and mean costs derived from Optum's deidentified Clinformatics Data Mart Database. Methods We designed a model to estimate adjusted economic offsets that combined respective patiromer and SZC HF hospitalization (25.1 and 35.8; difference 10.7 [95% confidence interval (CI)2, 2.6 to 18.8]) and edema event (3.4 and 7.1; difference 3.6 [95% CI, 1.7 to 7.1]) rates/100 person-years from the original published work with costs from our parallel data extract spanning 2019-2021, adjusted to 2021 US dollars. Results In a base case of mean HF hospitalization, edema event, and 30-count potassium-binder prescription costs from our data extract, the estimated mean savings with patiromer was $1428 per person per year (95% CI, -$1508 to $4652). Respective costs per person per year for patiromer versus SZC were $8526 versus $12,622 (difference $4096 [95% CI, $116 to $7320]) for HF hospitalization and edema events, and $10,649 versus $7981 (difference -$2668) for potassium binders, totaling $19,175 for patiromer versus $20,603 for SZC. Conclusions With differing drug costs, hospitalization and ED costs offset this difference when event rates were numerically small. Model outcomes were driven by HF hospitalization cost and least influenced by edema ED visit cost. A limitation was that the Clinformatics Data Mart data extract may differ from the original work.