Sanaka M, Takano K, Shimakura K, Koike Y, Mineshita S
Department of Preventive Medicine, Tokyo Medical and Dental University, Japan.
Gerontology. 1995;41(6):332-42. doi: 10.1159/000213705.
To develop a new method for accurately predicting creatinine clearance (Ccr) in the debilitated elderly without urine collections, the total muscle volume of both thighs (MV thigh), as a new predictive parameter, was calculated using computed tomography in 68 debilitated patients aged 61-92 years. A regression line between 24-hour urinary creatinine excretion and MV thigh was divided by serum creatinine (Scr), and then the following formula was derived: Ccr (ml/min) = 9 x [MV thigh (cm3) - 100]/[1,000 x Scr (mg/dl)] Predicted Ccr by the new method more closely correlated with measured Ccr (r = 0.862) than did predicted Ccr by Cockcroft and Gault's method (the C-G method) (r = 0.727). Statistical analysis of prediction error (= predicted Ccr-measured Ccr) suggested that the new method could provide more accurate and less biased estimations of Ccr than did the C-G method, even in patients with renal insufficiency. By using computed tomography, we have proposed a more accurate method for predicting Ccr of the debilitated elderly than the C-G method, although the new method has inherent disadvantages of radiation exposure and high cost.
为开发一种无需收集尿液就能准确预测衰弱老年人肌酐清除率（Ccr）的新方法，我们对68名年龄在61 - 92岁的衰弱患者进行了计算机断层扫描，计算双侧大腿的总肌肉体积（MV大腿）作为新的预测参数。将24小时尿肌酐排泄量与MV大腿之间的回归线除以血清肌酐（Scr），得出以下公式：Ccr（ml/min）= 9×[MV大腿（cm³）- 100]/[1000×Scr（mg/dl）]。与Cockcroft和Gault方法（C - G方法）预测的Ccr（r = 0.727）相比，新方法预测的Ccr与实测Ccr的相关性更强（r = 0.862）。对预测误差（=预测Ccr - 实测Ccr）的统计分析表明，即使在肾功能不全的患者中，新方法也能比C - G方法提供更准确、偏差更小的Ccr估计值。通过计算机断层扫描，我们提出了一种比C - G方法更准确的预测衰弱老年人Ccr的方法，尽管新方法存在辐射暴露和成本高的固有缺点。
