Sodium Zirconium Cyclosilicate Duration and Hyperkalemia-Related Healthcare Encounters in Patients with Heart Failure and Cardio/Renal Dysfunction: The GALVANIZE Outcome Study.

BACKGROUND AND OBJECTIVE: Patients with heart failure or cardio/renal dysfunction (chronic kidney disease, end-stage kidney disease, or heart failure) are at increased risk of hyperkalemia. Sodium zirconium cyclosilicate (SZC) treats hyperkalemia, but the impact of SZC treatment duration on healthcare resource utilization in these populations is unclear. This study, GALVANIZE Outcome, assessed healthcare resource utilization associated with short-term versus long-term outpatient SZC use in matched cohorts of SZC users with heart failure and, separately, cardio/renal dysfunction. METHODS: Data from a large US claims database (7/2018-12/2022) were used to identify adults with heart failure or cardio/renal dysfunction initiating outpatient SZC (index date). Long-term (> 90 days) and short-term SZC users (≤ 30 days) were matched on key baseline characteristics using a two-step approach: exact matching followed by propensity score matching. Rates of hyperkalemia-related hospitalizations or emergency department visits and hyperkalemia-related hospitalizations were compared between long-term and short-term SZC users during the follow-up from index to the earliest of 6 months post-index, end of data availability, new potassium binder use, or reinitiation of SZC post-discontinuation. RESULTS: Among 942 matched heart failure pairs and 2892 matched cardio/renal pairs, long-term SZC users had fewer hyperkalemia-related hospitalizations or emergency department visits compared with short-term users, with reductions of 36% in the heart failure sample and 40% in the cardio/renal dysfunction sample; the respective reductions were 39% and 37% for hyperkalemia-related hospitalizations alone (all p < 0.001). CONCLUSIONS: Long-term SZC use is associated with significant reductions in hyperkalemia-related hospitalizations or emergency department visits compared with short-term use among patients with heart failure or cardio/renal dysfunction.