[Differences between the CKD-EPI and the MDRD equations when estimating the glomerular filtration rate in hypertensive patients].

Objective: To analyze the agreement in glomerular filtration rate (GFR) estimated with CKD-EPI and MDRD-IDMS equations in a cohort of hypertensive patients.
Methods: We included consecutively 478 hypertensive patients, mean age 57.58 yr (SD: 12.34), 68.3% males. The estimation of GFR was performed with MDRD-IDMS and CKD-EPI equations and we analyzed the agreement between them.
Results: The estimation of GFR with CKD-EPI was 4.37 (95%:3.73-4.19) mL/min/1,73 m2 higher than MDRD-IDMS, overall and by gender (males 3.99; females 5.04). In patients under 65 years the difference was greater, 6.55 (95%:5.95-7.15) mL/min/1.73 m2 in both men 6.07 and women 6.48. However, we found no significant difference over 65 years. Intraclass correlation coefficient was 0.904 (95% CI:0.886-0.919), 0.897 men and 0.917 women and Kappa index 0.848 (95% CI :0.795-0.889), 0.845 men and 0.852 women.
Conclusion: CKD-EPI equation estimated a higher GFR in hypertensive patients under 65 years and reclassified in stage 1 patients classified in stage 2 by MDRD-IDMS.