Liberal fruit and vegetable intake in patients with advanced CKD with or without Sodium zirconium cyclosilicate.

INTRODUCTION: Higher dietary potassium intake is associated with lower blood pressure, better kidney outcomes and improved survival. However, the risk of hyperkalemia limits implementation of healthy potassium-rich diets in patients with chronic kidney disease(CKD). Novel potassium binders such as sodium zirconium cyclosilicate(SZC) may enable a more liberal intake of potassium-rich diets and thereby enable their cardiorenal benefits. METHODS: This randomized, crossover, non-inferiority clinical trial included 16 CKD patients receiving RAAS inhibitors. Participants followed, in a randomized order, a potassium-rich diet for 6 weeks (adding 40mmol potassium/day via extra fruits, vegetables and nuts) or their regular diet. Hyperkalemia (>5.5mmol/l) was managed with SZC, while continuing the diet. The primary endpoint was serum potassium after 6 weeks, with a non-inferiority margin of 0.5mmol/l. RESULTS: At 6 weeks, there was no significant difference in serum potassium between the control and potassium-enriched diet phases (between-group difference 0.03mmol/L, 95%CI-0.32to0.27;p=0.850). In contrast,24-hour urinary potassium excretion increased significantly during the potassium-enriched diet (between-group difference 24.7mmol/24h, 95%CI8.0to 41.3; p=0.005). Two patients developed hyperkalemia (5.9 and 6.1 mmol/L) and were treated with SZC, after which the diet was continued without recurrence. CONCLUSION: A potassium-rich diet was consistent with non-inferior serum potassium levels compared with a regular diet at 6 weeks in patients with advanced CKD receiving RAAS inhibition. Hyperkalemia occurred in a minority of patients, and was effectively managed with SZC, allowing continuation of both the diet and RAAS inhibition. These findings suggest that a potassium-rich diet may be feasible in selected patients with advanced CKD, with careful monitoring and use of SZC when needed.