Low urinary potassium excretion is significantly associated with progression of chronic kidney disease (CKD), regardless of age or the presence of diabetes or proteinuria, a recent study suggests.
In a study of 1821 patients from the Korean Cohort Study for Outcomes in Patients with CKD, patients in the lowest quartile of urinary potassium-to-creatinine ratio had a significant 47% increased risk of CKD progression compared with those in the highest quartile, in a fully adjusted model, investigators reported in the Clinical Journal of the American Society of Nephrology.
Of the 1821 patients, 855 provided 24-hour urine specimens. In this subset, patients in lowest quartile of spot urinary potassium, 24-hour urinary potassium excretion, and spot urinary potassium-to-creatinine ratio had a significant 3.8-, 3.0, and 1.9-fold increased risk of CKD progression, respectively, compared with those in the highest quartile.
The investigators, led by Seung Hyeok Han, MD, of the Institute of Kidney Disease Research at Yonsei University in Seoul, Korea, defined CKD progression as a 50% of greater decrease in estimated glomerular filtration rate from baseline and onset of end-stage renal disease. CKD progression occurred in 392 patients (22%) during 5326 person-years of follow-up. The association between low urinary potassium excretion and CKD progression remained significant regardless of age (less than 60 vs 60 years or older) or the presence or absence of diabetes and proteinuria.
“Our robust findings suggest potential prognostic value of urinary potassium excretion for progression of CKD,” Dr Han’s group concluded.
Kim HW, Park JT, Yoo TH, et al. Urinary potassium excretion and progression and chronic kidney disease. Clin J Am Soc Nephrol. 2019; published online ahead of print.