Estimating Glomerular Filtration Rate in 2012 - Does the New Chronic Kidney Disease Epidemiology Equation Fare Better than Older Equations?

Measuring or estimating glomerular filtration rate (GFR) is still considered the best way to apprehend global renal function. In 2009, the Chronic Kidney Disease Epidemiology (CKD-EPI) equation was proposed as a better estimator of GFR than the Modification of Diet in Renal Disease (MDRD) study equation. It is supposed to underestimate GFR to a lesser degree in higher GFR levels. In this article, we present and discuss the performances of this new equation. Based on articles published between 2009 and 2012, we underline its advantages, notably better knowledge of chronic kidney disease prevalence, but also its limitations, especially in some specific populations. Our conclusion is that all equations are estimations and that nephrologists should always remain cautions in their interpretation.