Measurements of 24-hour urinary sodium (24hrUNa) and potassium (24hrUK) excretion are useful in hypertensives but 24-hour urine collection may be difficult or unreliable. We compared three formulas (Tanaka, Kawasaki, Pan American Health Organization [PAHO]) proposed to estimate 24hrUNa and 24hrUK based on spot urine measurements. We studied 382 patients admitted to a hypertension unit. Sodium, potassium, and creatinine levels were measured using standard laboratory methods in a morning urine sample, followed by 24-hour urinary collection. Agreement between estimated and measured 24hrUNa and 24hrUK was evaluated using the Pearson correlation and Bland-Altman plots. Measured 24hrUNa was 158 ± 75 mmol/d and 24hrUK was 54 ± 24 mmol/d. The correlation coefficient was r = 0.53 for estimated versus measured 24hrUNa, r = 0.69–0.73 for estimated versus measured 24hrUK (all P < .001). The mean bias for 24hrUNa was significantly smaller for Tanaka (10.5 mmol/d) and PAHO (11.5 mmol/d) compared with Kawasaki formula (−29.9 mmol/d). The mean bias for 24hrUK was significantly smaller for Kawasaki (7.3 mmol/d) and PAHO (8.3 mmol/d) compared with Tanaka formula (16.5 mmol/d). Using a single morning urine sample, we found the PAHO formula to be the best for predicting mean 24hrUK and 24hrUNa in hospitalized hypertensive patients. However, precision and accuracy of all the evaluated formulas was inadequate.

测量高血压患者24小时尿钠（24hrUNa）和钾（24hrUK）的排泄量是有用的，但24小时尿液收集可能很困难或不可靠。我们比较了三个公式（田中，川崎，泛美卫生组织[PAHO]），这些公式建议根据尿液现场测量结果估算24hrUNa和24hrUK。我们研究了382名进入高血压病房的患者。使用标准实验室方法在早晨尿液样本中测量钠，钾和肌酐的水平，然后收集24小时尿液。使用Pearson相关图和Bland-Altman图评估和估计了24hrUNa和24hrUK之间的一致性。测得的24hrUNa为158±75 mmol / d，24hrUK为54±24 mmol / d。相对于24hrUNa估计值，相关系数为r = 0.53，r = 0.69-0。P  <.001）。与川崎公式（-29.9 mmol / d）相比，田中（10.5 mmol / d）和PAHO（11.5 mmol / d）的24hrUNa平均偏差明显较小。与田中公式（16.5 mmol / d）相比，川崎（7.3 mmol / d）和PAHO（8.3 mmol / d）的24hrUK平均偏差显着较小。使用一个早晨的尿液样本，我们发现PAHO公式最适合预测住院高血压患者的平均24hrUK和24hrUNa。但是，所有评估公式的精确度和准确性均不足。