MDRD versus CKD-EPI equation to estimate glomerular filtration rate in kidney transplant recipients

Background. The new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine-based equation
<br />was developed to address the systematic underestimation of the glomerular filtration rate (GFR) by the Modification
<br />of Diet in Renal Disease (MDRD) Study equation in patients with a relatively well-preserved kidney function. The
<br />performance of the new equation for kidney transplant recipients is discussed.
<br />Methods. We analyzed the performances of the CKD-EPI equation in comparison with the MDRD Study equation in
<br />825 stable kidney transplant recipients. Bias, precision, and accuracy within 30% of true GFR were determined. GFR
<br />was measured by urinary clearance of inulin (n=488) and plasma clearance of 51Cr-EDTA (n=337).
<br />Results. Mean measured GFR (mGFR) was 50T19 mL/min/1.73 m2. On the whole cohort, bias was significantly lower
<br />for MDRD Study equation compared with CKD-EPI creatinine. This superiority translates into a better accuracy
<br />(80% and 74% for the MDRD and CKD-EPI creatinine, respectively). The best performance of the MDRD Study
<br />equation is confirmed both in the subgroups of patients with mGFR G60 mL/min/1.73 m2 and between 60 and
<br />90 mL/min/1.73 m2. For mGFR 990 mL/min/1.73 m2, there were no significant differences between the two
<br />equations in terms of performance.
<br />Conclusions. The CKD-EPI creatinine equation does not offer a better GFR prediction in renal transplant patients
<br />compared with the MDRD Study equation, even in the earlier CKD stages.