While the prevalence of hyperkalemia in patients with CKD has recently increased due to increased prescription of renin-angiotensin system inhibitors (RASi) [6, 7], discontinuation of RASi [8], or mineralocorticoid receptor antagonists [9] due to hyperkalemia may be associated with a higher risk of death and major adverse cardiovascular events; therefore, even drugs that cause hyperkalemia should be continued for the long-term prognosis of patients with CKD. Here, REN is linked to chronic kidney disease.