Prediction equations based on serum creatinine concentrations in estimating glomerular filtration rate in patients with chronic kidney diseases (Prediction equations in estimating glomerular filtration rate in patients with chronic kidney diseases)

The aim was to examine the predictive value of two different equations for glomerular filtration rate (GFR) assessment: Cockcroft-Gault (CG) and modification of diet in renal disease (MDRD) in patients with chronic kidney diseases(CKD). We also aimed to compare sensitivity and specificityof the predictive equations in renal function assessment. Thestudy included 75 patients with CKD who were further dividedinto four groups according to the stages of disease (CKDStage 1-4) and 25 healthy subjects. The GFR was estimatedusing CG and MDRD equations. The estimated GFR valuesusing the MDRD equation in all groups were lower comparedto those calculated using the CG equation. In patientswith CKD stage 1, GFR was significantly lower as estimatedby MDRD compared to CG equation (p=0.032). The ROC curves for estimated GFR using CG and MDRD equations in CKD patients vs healthy subjects were significant (AUC for CG 0.839 and for MDRD 0.923; p<0.0005). The optimal cutoff value for GFR estimated by CG equation was 62.86 mL/min (sensitivity 81.25%; specificity 76%) and for estimated GFR using MDRD equation 57.2 mL/min/1.73° m2 (sensitivity91.3%; specificity 81%). MDRD equation yields higher sensitivity and specificity in predicting GFR in patients with CKD compared to CG equation. Key words: chronic kidney disease, glomerular filtration rate, Cockcroft-Gault equation, modification of diet in renal disease (MDRD) study equation