Department of Preventive Medicine, Keimyung University School of Medicine, Daegu, South Korea.
Department of Preventive Medicine, Hanyang University College of Medicine, Seoul, South Korea.
Med Sci Monit. 2019 Feb 8;25:1061-1070. doi: 10.12659/MSM.913504.
BACKGROUND Dietary potassium has negative outcomes in patients with mildly impaired kidney function, while having positive outcomes in patients with hypertension. The association of dietary potassium intake with chronic kidney disease (CKD) development, with presence of hypertension, was studied in the Korean rural population with mildly impaired kidney function. MATERIAL AND METHODS From 3 rural areas of Korea, 5064 participants age ≥40 with CKD stage 2 at baseline were recruited. Patients were classified according to the quartile of dietary potassium intake. Newly developed CKD, defined as estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m² at the time of follow-up, and eGFR decline, defined as eGFR decrease >15% at follow-up, were studied. The effect of dietary potassium on CKD development and eGFR decline were studied by Cox proportional hazard models. The association of potassium with blood pressures and C-reactive protein was also studied to examine the underlying mechanisms. RESULTS Compared to 8.6% in normotensives, 15.7% of hypertensives developed CKD. The hazard ratio (HR) (95% confidence interval) of CKD was lower in high potassium diet only in hypertensives, with 0.60 (0.37-0.99) in the highest quartile. The eGFR decline was also lower in patients with higher potassium diet, with 0.70 (0.50-0.98) in Q3 and 0.54 (0.34-0.85) in Q4. Potassium intake has also been shown to decrease high diastolic blood pressure development (>90 mmHg) in hypertensives at 0.45 (0.25-0.83). CONCLUSIONS Dietary potassium was associated with lower risk of CKD development and eGFR decline, and this association was observed only in hypertensives.
在肾功能轻度受损的患者中，膳食钾的摄入与不良结局相关，而在高血压患者中，膳食钾的摄入则与良好结局相关。本研究旨在探讨在肾功能轻度受损的韩国农村人群中，膳食钾摄入量与高血压合并慢性肾脏病（CKD）进展的关系。
本研究共纳入了来自韩国 3 个农村地区的 5064 名年龄≥40 岁、基线时 CKD 分期为 2 期的患者。根据膳食钾摄入量的四分位间距将患者进行分类。随访时估计肾小球滤过率（eGFR）<60mL/min/1.73m²定义为新发 CKD，eGFR 下降定义为随访时 eGFR 下降>15%。采用 Cox 比例风险模型研究膳食钾对 CKD 进展和 eGFR 下降的影响。还研究了钾与血压和 C 反应蛋白的关系，以探讨其潜在机制。
与血压正常者的 8.6%相比，高血压患者中 15.7%发生了 CKD。仅在高血压患者中，高钾饮食组的 CKD 发生风险较低（HR：0.60，95%CI：0.37-0.99），而在最高四分位数组中 HR 为 0.60（95%CI：0.37-0.99）。在接受高钾饮食的患者中，eGFR 下降也较低，第 3 四分位数组为 0.70（0.50-0.98），第 4 四分位数组为 0.54（0.34-0.85）。钾摄入量还与高血压患者中舒张压（>90mmHg）的发生率降低相关，风险比（HR）为 0.45（0.25-0.83）。
膳食钾与 CKD 进展和 eGFR 下降的风险降低相关，这种相关性仅在高血压患者中观察到。
