Background: The aim of this study was to compare the use of the ideal weight with the use of the patient's actual weight in the C-G (Cockcroft-Gault) formula for the measurement of the GFR (Glomerular Filtration Rate). We also aimed to compare the results of the calculations explained above with the results of the MDRD (Modification of Diet in Renal Disease) formula and CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) results of the classical 24-hour creatinine clearance method.
Methods: Creatinine clearance values, which were obtained from 24-hour urine collection, were compared with the values from the C-G formula in which each patient's ideal weight was used, with the values from the C-G for- mula in which each patient's actual body weight was used, and with the MDRD Formula and CKD-EPI.
Results: The correlation analysis between 24-hour creatinine clearance and the GFR obtained from the C-G formula with adjusted ideal weight in the Control group, Group I (patients with diabetes mellitus) and Group II resulted in values of r = 0.526, 0.576, and 0.850 (p < 0.0001), respectively. The correlation analysis between 24-hour creatinine clearance and the MDRD formula among the same groups resulted in r = 0.814, 0.682, and 0.861 (p < 0.0001), respectively. The correlation analysis between creatinine clearance and the CKD-EPI formula among the same groups resulted in r = 0.821, 0.679, and 0.871 (p < 0.0001), respectively.
Conclusions: The results of the CKD-EPI formula were the most compatible with the results of 24-hour urine cre- atinine clearance which is used in clinical practice, especially in the control and diabetic group.