Estimating glomerular filtration rate in hypertensive subjects: Comparison of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) Study equations

Abstract

Background.The Modification of Diet in Renal Disease (MDRD) Study equation is the most commonly used formula for estimation of glomerular filtration rate (eGFR). Recently, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) developed a new equation to provide a more accurate estimate of GFR among individuals with normal or mildly reduced renal function.

Aim. To compare the MDRD and CKD-EPI equations in hypertensive population treated in general practice.

Methods. The MDRD and CKD-EPI equations were applied to a cohort of 994 hypertensive subjects aged 45–70 years without cardiovascular or renal disease or previously known diabetes.

Results. The prevalence of CKD stage 3 (eGFR 30–59 mL/min per 1.73 m²) was 6.7% (95% CI 5.3–8.5) (67/994) according to the MDRD formula and 3.7% (95% CI 2.6–5.1) (37/994) according to the CKD-EPI formula. Of the 67 subjects classified as having CKD stage 3 according to the MDRD equation, 30 (44.8%) were reclassified as ‘no-CKD’ by the CKD-EPI equation. These subjects were mostly women 26/30 (87.7%).

Conclusion. Using the CKD-EPI equation leads to lower prevalence estimates for CKD than the MDRD equation in a hypertensive population treated in general practice.