Validation of predictive equations for glomerular filtration rate in the Saudi population.
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 cystatin C, creatinine clearance, reciprocal of creatinine, and inulin clearance in 32 Saudi subjects with different stages of renal disease. We compared 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 creatinine was 199 +/- 161 micromol/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 creatinine (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 creatinine 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, chronic kidney disease stages when compared to other GFR predictive equations.
Al Wakeel
Jamal S
JS
Division of Nephrology, Department of Medicine, King Khalid Hospital, King Saud University, Riyadh, Saudi Arabia. jwakeel@ksu.edu.sa
Hammad
Durdana
D
Al Suwaida
Abdulkareem
A
Tarif
Nauman
N
Chaudhary
Abdulrauf
A
Isnani
Arthur
A
Albedaiwi
Waleed Ahmed
WA
Mitwalli
Ahmad H
AH
Ahmad
Shaik Shaffi
SS
D000328:Adult; D000368:Aged; D044466:Asian People; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007444:Inulin; D007674:Kidney Diseases / Q000097:blood / Q000208:ethnology* / Q000503:physiopathology* / Q000601:surgery; D016030:Kidney Transplantation / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012529:Saudi Arabia / Q000453:epidemiology; D055815:Young Adult
D015415:Biomarkers; D055316:Cystatin C; D007444:Inulin; D003404:Creatinine