Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand.
Center of Excellence in Kidney Metabolic Disorders, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Int Urol Nephrol. 2021 Jul;53(7):1463-1471. doi: 10.1007/s11255-020-02773-8. Epub 2021 Jan 11.
Hypokalemia is highly prevalent in chronic peritoneal dialysis (PD) patients worldwide, particularly in Thailand. This study aims to investigate the major determinants of hypokalemia in Thai PD patients.
A cross-sectional study was performed in chronic PD patients at 4 PD centers in Bangkok, Thailand. Hypokalemia was defined if the average serum potassium level during the last 3 consecutive visits was < 3.5 mEq/L. Patients and/or their caregivers were asked to perform a 3-day dietary food record and take pre- and post-meal pictures following the instructed protocol. Daily dietary nutrients, including potassium, were estimated by a single dietician using INMUCAL-N software. Total potassium excretion was determined by 24-h PD effluents and urine collection. Intracellular and extracellular water values (ICW and ECW, respectively) were measured by electrical bioimpedance assay (BIA) to indirectly explore the role of intracellular potassium shift in hypokalemia.
Among 60 eligible PD patients, 19 (31%) had hypokalemia. Hypokalemic patients had significantly lower dietary potassium intake (24.4 ± 11.1 vs. 30.5 ± 9.4 mEq/day, p = 0.031) and lower total potassium excretion (28.5 ± 8.4 vs. 36.7 ± 11.2 mEq/day, p = 0.006) compared to normokalemic patients. Both groups had comparable values of ICW and ECW. On logistic regression, there was no significant correlation between hypokalemia and daily PD exchange volume, total Kt/Vurea, residual renal function, concurrent medications (insulin, diuretics, renin-angiotensin-aldosterone inhibitor, and beta-blockers) or ICW. Low dietary potassium was an independent risk factor for hypokalemia.
Low dietary potassium intake, rather than increased potassium excretion or intracellular shift, is the major contributing factor of hypokalemia in Thai chronic PD patients. Dietary intervention or potassium supplement protocol should be implemented.
低钾血症在全球范围内的慢性腹膜透析（PD）患者中非常普遍，尤其是在泰国。本研究旨在探讨泰国 PD 患者低钾血症的主要决定因素。
在泰国曼谷的 4 个 PD 中心进行了一项横断面研究。如果过去 3 次连续就诊的平均血清钾水平 < 3.5 mEq/L，则定义为低钾血症。患者及其护理人员被要求按照规定的方案进行为期 3 天的饮食记录，并在餐前和餐后拍照。由一名营养师使用 INMUCAL-N 软件估计每日饮食营养素，包括钾。通过 24 小时 PD 流出液和尿液收集来确定总钾排泄量。通过生物电阻抗分析（BIA）测量细胞内和细胞外水值（ICW 和 ECW），以间接探讨细胞内钾转移在低钾血症中的作用。
在 60 名符合条件的 PD 患者中，有 19 名（31%）患有低钾血症。低钾血症患者的饮食钾摄入量明显较低（24.4 ± 11.1 与 30.5 ± 9.4 mEq/天，p=0.031），总钾排泄量也较低（28.5 ± 8.4 与 36.7 ± 11.2 mEq/天，p=0.006）。两组的 ICW 和 ECW 值均无显著差异。在逻辑回归中，低钾血症与每日 PD 交换量、总 Kt/Vurea、残余肾功能、同时使用的药物（胰岛素、利尿剂、肾素-血管紧张素-醛固酮抑制剂和β受体阻滞剂）或 ICW 之间无显著相关性。低饮食钾是低钾血症的独立危险因素。
低饮食钾摄入，而不是增加钾排泄或细胞内转移，是泰国慢性 PD 患者低钾血症的主要原因。应实施饮食干预或钾补充方案。
