Alcântara P, Gonçalves F, Moreira C, Gonzalez M A
Serviço de Medicina I, Hospital de Santa Maria, Lisboa.
Acta Med Port. 1998 Aug-Sep;11(8-9):767-72.
This study was undertaken to assess the value of Cockroft-Gault Formula (FCG) in the patients of an Internal Medicine ward.
FCG was compared with creatinine clearance (DC) adjusted for corporal area. Serum creatinine was measured after 24 h urine collection and 8 h fast. By the subtraction of FCG from DC, the variable difference (DIF) was calculated. FCG was calculated using total body weight (PT) and lean body weight (PS). All patients were included unless they had renal failure.
Renal function was calculated in 92 patients, 33 women and 59 men. Mean age was 60.8 +/- 17.9 (13-87). Mean FCG (64.7 +/- 27.4) and mean DC (68.4 +/- 32.6) were not significantly different and a correlation between them was found (r = 0.68; p < 0.001). Using PS to estimate FCG the correlation coefficient was increased to 0.75 (p < 0.001). DC and FCG using PT or PS correlated inversely with age (r = 0.59; r = 0.53; r = 0.66, respectively; p < 00.1). In a cluster analysis model we could find that for extremes of renal function FCG overestimated (DIF = -10.4 +/- 13.3) or underestimated (DIF = 29.8 +/- 29.7) DC. The main influence for the difference between the two methods was body weight (r = -0.69; p < 0.001). The distribution by diagnosis led to two classes of patients for whom DIF was significantly different (p < 0.02), and body weight was the main factor.
Cockroft-Gault formula, although correlating with creatinine clearance, over or underestimates creatinine clearance for extremes of renal function. Age and body weight were the main factors for the differences found between the two methods.
本研究旨在评估Cockcroft - Gault公式（FCG）在内科病房患者中的价值。
将FCG与根据体表面积调整的肌酐清除率（DC）进行比较。在收集24小时尿液并禁食8小时后测量血清肌酐。通过用DC减去FCG来计算变量差值（DIF）。使用总体重（PT）和瘦体重（PS）来计算FCG。除非患有肾衰竭，否则所有患者均纳入研究。
对92例患者（33名女性和59名男性）的肾功能进行了计算。平均年龄为60.8±17.9（13 - 87岁）。平均FCG（64.7±27.4）和平均DC（68.4±32.6）无显著差异，且二者之间存在相关性（r = 0.68；p < 0.001）。使用PS估算FCG时，相关系数增至0.75（p < 0.001）。使用PT或PS计算的DC和FCG与年龄呈负相关（分别为r = 0.59；r = 0.53；r = 0.66；p < 0.01）。在聚类分析模型中，我们发现对于肾功能的极端情况，FCG高估（DIF = -10.4±13.3）或低估（DIF = 29.8±29.7）了DC。两种方法之间差异的主要影响因素是体重（r = -0.69；p < 0.001）。按诊断分类导致两类患者的DIF存在显著差异（p < 0.02），且体重是主要因素。
Cockcroft - Gault公式虽然与肌酐清除率相关，但对于肾功能的极端情况会高估或低估肌酐清除率。年龄和体重是两种方法之间差异的主要因素。
