Validation of predictive equations for glomerular filtration rate in the Saudi population

Abstract EN

Predictive equations provide a rapid method of assessing glomerular filtration rate (GFR).

To compare the various predictive equations for the measurement of this parameter in the Saudi population, we measured GFR by the Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault formulas, cystatin C, reciprocal of cystitis C, cretonne clearance, reciprocal of cretonne, and inulin clearance in 32 Saudi subjects with different stages of renal disease.

We com-pared GFR measured by inulin clearance and the estimated GFR by the equations.

The study included 19 males (59.4 %) and 13 (40.6 %) females with a mean age of 42.3 ± 15.2 years and weight of 68.6 ± 17.7 kg.

The mean serum cretonne was 199 ± 161 μmol / L.

The GFR measured by inulin clearance was 50.9 ± 33.5 mL / min and the estimated by Cockcroft-Gault and by MDRD equations was 56.3 ± 33.3 and 52.8 ± 32.0 mL / min, respectively.

The GFR estimated by MDRD revealed the strongest correlation with the measured inulin clearance (r = 0.976, P = 0.0000) followed by the GFR estimated by Cockcroft-Gault, serum cystatin C, and serum cretonne (r = 0.953, P = 0.0000) (r= 0.787, P = 0.0001) (r = -0.678, P = 0.001), respectively.

The reciprocal of cystatin C and serum cretonne revealed a correlation coefficient of 0.826 and 0.93, respectively.

Cockroft-Gault formula overestimated the GFR by 5.40 ± 10.3 mL / min in comparison to the MDRD formula, which exhibited the best correlation with inulin clearance in different genders, age groups, body mass index, renal transplant recipients, and chronic kidney disease stages when compared to other GFR predictive equations.