A comparison of three methods to estimate baseline creatinine for RIFLE classification

作者：Jakub Závada, Eric A. J. Hoste, Rodrigo Cartin‐Ceba, Paolo Calzavacca, Ognjen Gajic, Gilles Clermont, Rinaldo Bellomo, John A. Kellum, for the AKI6 investigators · 发表于：Nephrology Dialysis Transplantation · 年份：2010 · DOI：10.1093/ndt/gfp766 · 被引用次数：270 · 研究领域：Acute Kidney Injury Research、Chronic Kidney Disease and Diabetes、Clinical Nutrition and Gastroenterology

BACKGROUND: A pre-morbid 'baseline' creatinine is required in order to diagnose and stage acute kidney injury (AKI) using the RIFLE classification. Estimation of baseline creatinine by solving the Modification of Diet in Renal Disease (MDRD) equation assuming a glomerular filtration rate of 75 ml/min/1.73 m(2) has been widely used but never validated. METHODS: We analysed four cohorts of intensive care unit (ICU) patients from three centres (two from Pittsburgh and one from Mayo and Austin). Three cohorts consisted of preselected patients without AKI (Pittsburgh 1 n = 1048, Mayo n = 737, Austin n = 333), and measured creatinine values in these cohorts were taken to represent baseline creatinine values. The last cohort (Pittsburgh 2 n = 468) consisted of unselected ICU patients with baseline creatinine values recorded within 1 year before ICU admission. Using the Pittsburgh 1 cohort, we derived an equation using the same anthropometric variables as the MDRD equation: baseline creatinine = 0.74 - 0.2 (if female) + 0.08 (if black) + 0.003 × age (in years). We then compared measured creatinine in the Mayo and Austin cohorts and recorded creatinine in the Pittsburgh 2 cohort to the estimated creatinine from: (i) the MDRD equation; (ii) our new equation; (iii) a gender-fixed creatinine of 0.8 mg/dl for females and 1.0 mg/dl for males. RESULTS: Using any of the three methods, the median absolute error of the estimates was of the order of 0.1-0.2 mg/dl, and overall accuracy was simil...