Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University, Seoul, Korea.
Department of Prevention and Management, School of Medicine, Inha University, Incheon, Korea.
Clin J Am Soc Nephrol. 2019 Mar 7;14(3):330-340. doi: 10.2215/CJN.07820618. Epub 2019 Feb 14.
Data on whether low or high urinary potassium excretion is associated with poor kidney outcome have been conflicting. The aim of this study was to clarify the association between urinary potassium excretion and CKD progression.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We investigated the relationship between lower urinary potassium excretion and CKD progression and compared three urinary potassium indices among 1821 patients from the Korean Cohort Study for Outcome in Patients with CKD. Urinary potassium excretion was determined using spot urinary potassium-to-creatinine ratio, spot urinary potassium concentration, and 24-hour urinary potassium excretion. Patients were categorized into four groups according to quartiles of each urinary potassium excretion metric. The study end point was a composite of a ≥50% decrease in eGFR from baseline values and ESKD.
During 5326 person-years of follow-up, the primary outcome occurred in 392 (22%) patients. In a multivariable cause-specific hazard model, lower urinary potassium-to-creatinine ratio was associated with higher risk of CKD progression (adjusted hazard ratio, 1.47; 95% confidence interval, 1.01 to 2.12) comparing the lowest quartile with the highest quartile. Sensitivity analyses with other potassium metrics also showed consistent results in 855 patients who completed 24-hour urinary collections: adjusted hazard ratios comparing the lowest quartile with the highest quartile were 3.05 (95% confidence interval, 1.54 to 6.04) for 24-hour urinary potassium excretion, 1.95 (95% confidence interval, 1.05 to 3.62) for spot urinary potassium-to-creatinine ratio, and 3.79 (95% confidence interval, 1.51 to 9.51) for spot urinary potassium concentration.
Low urinary potassium excretion is associated with progression of CKD.
关于低尿钾排泄还是高尿钾排泄与肾脏结局不良相关的数据一直存在争议。本研究旨在阐明尿钾排泄与 CKD 进展之间的关系。
设计、设置、参与者和测量：我们调查了较低尿钾排泄与 CKD 进展之间的关系，并在韩国 CKD 患者结局队列研究中比较了 1821 例患者的三种尿钾指数。使用尿钾-肌酐比、尿钾浓度和 24 小时尿钾排泄来确定尿钾排泄。根据每个尿钾排泄指标的四分位数将患者分为四组。研究终点是 eGFR 从基线值下降≥50%和 ESKD 的复合终点。
在 5326 人年的随访期间，392 例（22%）患者发生了主要结局。在多变量原因特异性风险模型中，与最低四分位相比，最低尿钾-肌酐比值与 CKD 进展风险较高相关（调整后的风险比，1.47；95%置信区间，1.01 至 2.12）。用其他钾指标进行的敏感性分析也显示了在完成 24 小时尿液收集的 855 例患者中的一致性结果：与最高四分位相比，最低四分位的调整后风险比分别为 24 小时尿钾排泄 3.05（95%置信区间，1.54 至 6.04）、尿钾-肌酐比 1.95（95%置信区间，1.05 至 3.62）和尿钾浓度 3.79（95%置信区间，1.51 至 9.51）。
低尿钾排泄与 CKD 进展相关。
