Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Division of Nephrology, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
PLoS One. 2021 Dec 2;16(12):e0260408. doi: 10.1371/journal.pone.0260408. eCollection 2021.
The gold standard for estimating sodium intake is 24h urine sodium excretion. Several equations have been used to estimate 24h urine sodium excretion, however, a validated formula for calculating 24h urine sodium excretion from 12h urine collection has not yet been established. This study aims to develop novel equations for estimating 24h urine sodium excretion from 12h and random spot urine collection and also to validate existing spot urine equations in the Thai population. A cross-sectional survey was carried out among 209 adult hospital personnel. Participants were asked to perform a 12h daytime, 12h nighttime, and a random spot urine collection over a period of 24 hours. The mean 24h urine sodium excretion was 4,055±1,712 mg/day. Estimated urine sodium excretion from 3 different equations using random spot urine collection showed moderate correlation and agreement with actual 24h urine sodium excretion (r = 0.54, P<0.001, ICC = 0.53 for Kawasaki; r = 0.57, P<0.001, ICC = 0.44 for Tanaka; r = 0.60, P<0.001, ICC = 0.45 for INTERSALT). Novel equations for predicting 24h urine sodium excretion were then developed using variables derived from 12h daytime urine collection, 12h nighttime urine collection, random spot urine collection, 12h daytime with random spot urine collection, and 12h nighttime with random spot urine collection which showed strong correlation and agreement with actual measured values (r = 0.88, P<0.001, ICC = 0.87; r = 0.83, P<0.001, ICC = 0.81; r = 0.67, P<0.001, ICC = 0.62; r = 0.90, P<0.001, ICC = 0.90; and r = 0.83, p<0.001, ICC = 0.82 respectively). Bland-Altman plots indicated good agreement between predicted values and actual 24h urine sodium excretion using the new equations. Newly derived equations from 12h daytime and 12h nighttime urine collection with or without casual spot urine collection were able to accurately predict 24h urine sodium excretion.
估计钠摄入量的金标准是 24 小时尿液钠排泄量。已经有多种方程用于估计 24 小时尿液钠排泄量，但尚未建立从 12 小时尿液收集计算 24 小时尿液钠排泄量的验证公式。本研究旨在为从 12 小时和随机点尿收集估计 24 小时尿液钠排泄量开发新方程，并验证泰国人群中现有的点尿方程。一项横断面调查在 209 名成年医院工作人员中进行。要求参与者在 24 小时内进行 12 小时白天、12 小时夜间和随机点尿收集。平均 24 小时尿液钠排泄量为 4055±1712mg/天。使用随机点尿收集的 3 种不同方程估算的尿钠排泄量与实际 24 小时尿液钠排泄量呈中度相关和一致性（r = 0.54，P<0.001，ICC = 0.53 用于 Kawasaki；r = 0.57，P<0.001，ICC = 0.44 用于 Tanaka；r = 0.60，P<0.001，ICC = 0.45 用于 INTERSALT）。然后，使用源自 12 小时白天尿液收集、12 小时夜间尿液收集、随机点尿收集、12 小时白天和随机点尿收集、12 小时夜间和随机点尿收集的变量开发了预测 24 小时尿液钠排泄量的新方程，这些方程与实际测量值具有很强的相关性和一致性（r = 0.88，P<0.001，ICC = 0.87；r = 0.83，P<0.001，ICC = 0.81；r = 0.67，P<0.001，ICC = 0.62；r = 0.90，P<0.001，ICC = 0.90；r = 0.83，P<0.001，ICC = 0.82）。Bland-Altman 图表明，使用新方程预测值与实际 24 小时尿液钠排泄量之间具有良好的一致性。源自 12 小时白天和夜间尿液收集的新方程，无论是否有随机点尿收集，均能准确预测 24 小时尿液钠排泄量。
