Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China; Shanghai Medical Center of Kidney, Shanghai, People's Republic of China; Shanghai Institute of Kidney and Dialysis, Shanghai, People's Republic of China; Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, People's Republic of China; Hemodialysis Quality Control Center of Shanghai, Shanghai, People's Republic of China.
Department of Nephrology, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China; Shanghai Medical Center of Kidney, Shanghai, People's Republic of China; Shanghai Institute of Kidney and Dialysis, Shanghai, People's Republic of China; Shanghai Key Laboratory of Kidney and Blood Purification, Shanghai, People's Republic of China; Hemodialysis Quality Control Center of Shanghai, Shanghai, People's Republic of China.
J Ren Nutr. 2020 Jan;30(1):11-21. doi: 10.1053/j.jrn.2019.02.002. Epub 2019 Apr 5.
Spot urine sodium and associated estimating equations provide a suitable alternative assessment of 24-hour sodium excretion in many large-scale studies, but not in chronic kidney disease (CKD) patients with decreased renal function. Herein, we aimed to develop a novel predictive equation.
We retrospectively enrolled all CKD patients at Stage 1-4 who received spot and 24-hour urinary analysis in our single center from January 1, 2014 to December 31, 2017. Multiple linear regression analysis generated a predictive equation for estimating 24-hour sodium excretion from spot urine samples in the derivation cohort admitted from 2014 to 2015, and then we assessed this predictive equation in a validation cohort admitted from 2016 to 2017.
All 5,235 patients were finally analyzed and divided into derivation (n = 2,460) and validation (n = 2,775) cohort according to the admission date. We generated a predictive equation and defined it as "CKDSALT" equation because it was used for the estimation of salt intake in CKD patients. When we measured sodium excretion as the gold standard, we compared this novel validation with other 3 equations: Kawasaki, INTERSALT, and Tanaka. The Bland-Altman plots indicated that the CKDSALT equation showed the lowest bias with limits of agreement (bias = -1.25 mmol, 95% confidence interval -121.3 to 123.8), and the best performance in any subgroup analysis: male and female, old and young, different levels of body mass index, various levels of estimated glomerular filtration rate, and 24-hour urine volume. The CKDSALT equation also had the highest Pearson (0.745) and intraclass correlation coefficient (0.853, 95% confidence interval 0.841-0.863) in all validation cohort and the above subgroups.
Spot urine method by CKDSALT equation may be promising for estimating 24-hour urinary sodium excretion in CKD patients with normal renal function and patients with decreased estimated glomerular filtration rate.
在许多大规模研究中，单次尿钠和相关估算方程可作为 24 小时尿钠排泄的合适替代评估方法，但对于肾功能下降的慢性肾脏病（CKD）患者则不然。本研究旨在建立一种新的预测方程。
我们回顾性纳入了 2014 年 1 月 1 日至 2017 年 12 月 31 日在我院接受单次尿和 24 小时尿分析的 1-4 期 CKD 患者。多线性回归分析生成了一个用于估算 2014 年至 2015 年入院患者的单次尿样本中 24 小时钠排泄量的预测方程，然后在 2016 年至 2017 年入院的验证队列中评估该预测方程。
最终对 5235 例患者进行了分析，并根据入院日期分为推导队列（n=2460）和验证队列（n=2775）。我们生成了一个预测方程，并将其定义为“CKDSALT”方程，因为它用于估算 CKD 患者的盐摄入量。当我们将钠排泄量作为金标准进行比较时，与其他 3 个方程（Kawasaki、INTERSALT 和 Tanaka）相比，这个新的验证方程具有更低的偏差和更窄的一致性界限（偏差=-1.25mmol，95%置信区间-121.3 至 123.8）。在任何亚组分析中，该方程均表现最佳，包括男性和女性、年龄较大和较小、不同的身体质量指数、不同的估计肾小球滤过率水平以及 24 小时尿量。CKDSALT 方程在所有验证队列和上述亚组中的 Pearson 相关系数（0.745）和组内相关系数（0.853，95%置信区间 0.841-0.863）均最高。
在肾功能正常和估计肾小球滤过率下降的 CKD 患者中，使用 CKDSALT 方程的单次尿法可能是估计 24 小时尿钠排泄量的一种很有前途的方法。
