Performance of three glomerular filtration rate estimation equations in a population of sub-Saharan Africans with Type 2 diabetes.
We evaluated the performance of the Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Cockcroft-Gault (CG) equations against creatinine clearance (CrCl) to estimate glomerular filtration rate (GFR) in 51 patients with Type 2 diabetes.



The CrCl value was obtained from the average of two consecutive 24-h urine samples. Results were adjusted for body surface area using the Dubois formula. Serum creatinine was measured using the kinetic Jaffe method and was calibrated to standardized levels. Bland-Altman analysis and kappa statistic were used to examine agreement between measured and estimated GFR.



Estimates of GFR from the CrCl, MDRD, CKD-EPI and CG equations were similar (overall P = 0.298), and MDRD (r = 0.58; 95% CI: 0.36-0.74), CKD-EPI (r = 0.55; 95% CI: 0.33-0.72) and CG (r = 0.61; 95% CI: 0.39-0.75) showed modest correlation with CrCl (all P < 0.001). Bias was -0.3 for MDRD, 1.7 for CKD-EPI and -5.4 for CG. All three equations showed fair-to-moderate agreement with CrCl (kappa: 0.38-0.51). The c-statistic for all three equations ranged between 0.75 and 0.77 with no significant difference (P = 0.639 for c-statistic comparison).



The MDRD equation seems to have a modest advantage over CKD-EPI and CG in estimating GFR and detecting impaired renal function in sub-Saharan African patients with Type 2 diabetes. The overall relatively modest correlation with CrCl, however, suggests the need for context-specific estimators of GFR or context adaptation of existing estimators.
National Obesity Center, Yaoundé Central Hospital, Yaoundé, Cameroon.
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Agoons
National Obesity Center, Yaoundé Central Hospital, Yaoundé, Cameroon.|Diabetes Research Center, Brussels Free University-VUB, Brussels, Belgium.
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Balti
Department of Internal Medicine and Specialties, University of Yaoundé I, Yaoundé, Cameroon.|Nephrology Unit, Yaoundé General Hospital, University of Yaoundé 1, Yaoundé, Cameroon.
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Kaze
Department of Physiological Sciences and Biochemistry, University of Yaoundé 1, Yaoundé, Cameroon.
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Azabji-Kenfack
Department of Internal Medicine and Specialties, University of Yaoundé I, Yaoundé, Cameroon.|Nephrology Unit, Yaoundé General Hospital, University of Yaoundé 1, Yaoundé, Cameroon.
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Ashuntantang
Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.|Department of Medicine, Groote Schuur Hospital, University of Cape Town, Cape Town, South Africa.|The George Institute for Global Health, the University of Sydney, Sydney, NSW, Australia.
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Kengne
National Obesity Center, Yaoundé Central Hospital, Yaoundé, Cameroon.|Department of Internal Medicine and Specialties, University of Yaoundé I, Yaoundé, Cameroon.|Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, University of Yaoundé I, Yaoundé, Cameroon.
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Sobngwi
National Obesity Center, Yaoundé Central Hospital, Yaoundé, Cameroon.|Department of Internal Medicine and Specialties, University of Yaoundé I, Yaoundé, Cameroon.|Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, University of Yaoundé I, Yaoundé, Cameroon.
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Mbanya
D000328:Adult; D017954:Africa South of the Sahara; D000368:Aged; D044383:Black People; D003404:Creatinine / Q000097:blood / Q000378:metabolism* / Q000652:urine; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000378:metabolism*; D003928:Diabetic Nephropathies / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007677:Kidney Function Tests / Q000379:methods; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism
D003404:Creatinine