Impact of Sodium Zirconium Cyclosilicate Therapy on Nutrition Status in Patients with Hyperkalemia

Background: Restriction of oral potassium intake is a necessary dietary intervention for managing chronic hyperkalemia. These dietary changes may have negative impacts on nutrition status, particularly in geriatric cohorts with multiple comorbidities. Sodium zirconium cyclosilicate (SZC) is a newly introduced potassium binder intended for patients with hyperkalemia. We aimed to investigate whether the improvements in hyperkalemia with SZC therapy and the liberation of potassium intake restriction may improve nutrition status in a primarily geriatric patient cohort with chronic hyperkalemia. Methods: Patients who were maintained on SZC therapy for at least 3 months were retrospectively studied. Following the initiation of SZC and improvement in hyperkalemia, instructions on the restriction of potassium intake were loosened according to the institutional protocol. The change in nutrition status during the 3 month therapeutic period using SZC was investigated by referencing the prognostic nutritional index score (PNI), geriatric nutritional risk index score (GNRI), and controlling nutritional status (CONUT) scores. Results: A total of 24 patients (median age 78 years, 58% men, median estimated glomerular filtration rate 29.8 mL/min//1.73 m²) were included. Serum potassium level decreased significantly from 5.4 (5.1, 5.9) to 4.4 (4.2, 4.9) mEq/L without any drug-related adverse events, including hypokalemia. Nutrition-related scores, including the PNI score, the GNRI score, and the CONUT score, improved significantly following 3 months of SZC therapy (p < 0.05 for all). Psoas muscle volume and average days for one movement also improved significantly during the therapeutic period (p < 0.05 for both). Conclusions: Mid-term SZC therapy and liberation of potassium intake restriction might improve nutrition status in geriatric patients with chronic hyperkalemia.