Potassium Binder in CKD Patients (With Hyperkalemia) (DiPo Trial)

Combined Dietary Intervention in Hyperkalemic CKD Patients With Potassium Binder (With Hyperkalemia) (DiPo Trial)

This study hypothesizes that the administration of Sodium zirconium cyclosilicate in CKD patients with hyperkalemia while avoiding dietary potassium restriction will normalize their serum potassium levels. Additionally, we aim to assess the effects of a high potassium diet on renal function, endothelial function, acidosis, systemic inflammatory status and gut microbiota.

A diet rich in fruits and vegetables is associated with better outcomes in CKD patients. However, the presence of hyperkalemia can prevent patients from increasing plant-based foods in their diets. While hyperkalemia can have severe health consequences in advanced CKD, the decreased consumption of plant-based foods can be associated with adverse health outcomes in this population. Sodium zirconium cyclosilicate (SZC) is a non-absorbed cation exchanger that selectively binds potassium in the intestine. This study plans to enroll CKD patients with an eGFR ≤45mL/min and a serum potassium ≥ 5mEq/L, administering SZC to achieve normokalemia, and provide them with a diet rich in fruits and vegetables. Endothelial function, inflammatory biomarkers and stool microbiota will be measured to assess the potential benefits of providing a diet rich in fruits and vegetables, albeit rich in potassium, in advanced CKD patients. Because these patients are usually restricting the intake of plant-based proteins and foods due to the concerns of hyperkalemia, eliminating this serious and potentially-life threatening clinical condition might carry health benefits, such as improved endothelial function and decreased inflammation

All 20 CKD patients will be receiving a potassium binder while consuming a tailored diet of non-potassium restricted foods

Sodium zirconium cyclosilicate (SZC), a non-absorbed cation exchanger, selectively binds potassium in the intestine. SZC is in a powder form and will be provided to patients in packets containing 5g or 10gm of the medication. Participants will mix the contents of one packet with water (about 45mL). The drink should be stirred and drank immediately. If powder remains in the glass, then water should be added and the remainder of the drink should be consumed. Other medications should be taken 2 hours before or after SZC. At Day 0 and Day 1, participants will be taking SZC at 10gm three times a day. A serum potassium will be checked on Day 2; if serum potassium is <5.1mEq/L, then the dose will be decreased to the maintenance dose of 5gm per day. At each serum potassium checks, the medication dosage will be adjusted accordingly.

Changes in inflammation measured by IL-6, CRP, Soluble urokinase-type Plasminogen Activator Receptor (suPAR), Monocyte Chemoattractant Protein-1 (MCP-1), Tumor Necrosis Factor Receptor (TNF-R), Fibroblast Growth Factor 23 (FGF23)

We will perform 16S rRNA sequencing from stool samples to determine microbiota diversity and species determination.

Inclusion Criteria: Men and women over the age of 18 CKD stage 3-4 with an estimated GFR less or equal to 45 mL/min but greater than 15 mL/min Serum potassium level ≥5 mEq/L on two blood tests in the past 3 months but less than 6.5mEq/L Exclusion Criteria: On dialysis Have been on SZC in the past 3 months Reside in a nursing home Pregnant patients Patients with known cognitive disability History of bowel disease such as but not limited to short bowel syndrome, bowel obstruction, inflammatory bowel disease