RT Journal Article SR Electronic T1 Effects of Short-Term Potassium Chloride Supplementation in Patients with Chronic Kidney Disease JF Journal of the American Society of Nephrology JO J. Am. Soc. Nephrol. FD American Society of Nephrology SP ASN.2022020147 DO 10.1681/ASN.2022020147 A1 Gritter, Martin A1 Wouda, Rosa A1 Yeung, Stanley A1 Wieers, Michiel A1 Geurts, Frank A1 de Ridder, Maria A1 Ramakers, Christian A1 Vogt, Liffert A1 de Borst, Martin A1 Rotmans, Joris A1 Hoorn, Ewout YR 2022 UL http://jasn.asnjournals.org/content/early/2022/05/24/ASN.2022020147.abstract AB Background: Observational studies suggest that adequate dietary potassium intake (90-120 mmol/day) may be renoprotective, but the effects of increasing dietary potassium and the risk of hyperkalemia are unknown. Methods: This is a pre-specified analysis of the run-in phase of a clinical trial in which 191 patients (age 68 ± 11 years, 74% males, 86% European ancestry, eGFR 31 ± 9 mL/min/1.73 m2, 83% renin-angiotensin system inhibitors, 38% diabetes) were treated with 40 mmol KCl/day for two weeks. Results: KCl supplementation significantly increased urinary potassium excretion (72 ± 24 to 107 ± 29 mmol/day), plasma potassium (4.3 ± 0.5 to 4.7 ± 0.6 mmol/L), and plasma aldosterone (281 [198-431] to 351 [241-494] ng/L), but had no significant effect on urinary sodium excretion, plasma renin, blood pressure, eGFR, or albuminuria. Furthermore, KCl supplementation increased plasma chloride (104 ± 3 to 105 ± 4 mmol/L), reduced plasma bicarbonate (24.5 ± 3.4 to 23.7 ± 3.5 mmol/L) and urine pH (all P < 0.001), but did not change urinary ammonium excretion. Twenty-one participants (11%) developed hyperkalemia (plasma potassium 5.9 ± 0.4 mmol/L). They were older and had higher baseline plasma potassium. Conclusions: In patients with CKD stage G3b-4, increasing dietary potassium intake to recommended levels with potassium chloride supplementation raises plasma potassium by 0.4 mmol/L. This may result in hyperkalemia in older patients or those with higher baseline plasma potassium. Longer-term studies should address whether cardiorenal protection outweighs the risk of hyperkalemia.