Difference between estimated glomerulofiltration rate by modification of diet in renal diseases and Cockcroft-Gault formula in general population

To characterize the differences between the estimated glomerular filtration rate (eGFR) by using Cockcroft-Gault (CG) and Modification of Diet in Renal Diseases (MDRD) formula. We retrospectively reviewed individuals in a hospital-based health-check program from 2003 to 2006. eGFR was calculated by MDRD formula ( MDRD = 186 × [SCr]^(-1.154) × [age]^(-0.203) × [0.742 if female]) or CG ([(140-age) × weight (kg)]/ (SCr × 72) × [0.85 if female] and was adjusted for body surface area of 1.73 m^2). A total of 7832 (3264 men and 4559 women) individuals with a mean age of 64±11.4 year-old were studied. Mean eGFR by MDRD and CG formula was 78.6±21.3 and 71.5±21.6 (p＜0.0001) respectively. The mean MDRD-CG was 7.1± 10.7 revealing that MDRD estimates were higher than CG estimates. The values of MDRD-CG correlated positively with age (r=0.067, p＜0.0001) and negatively with body mass index (r= -0.549, p＜0.0001) and serum creatinine (r= -0.069, p＜0.0001). The MDRD-CG was significantly higher in male, individuals with hypertension, and those with diabetes (p＜0.001, p=0.002, and p＜0.001). In multiple linear regression analysis, age, gender, BMI, serum creatinine, hypertension and diabetes were independently associated with the differences between MDRD and CG formula. The difference between MDRD and CG formula is associated with age, gender, BMI, serum creatinine, hypertension, and diabetes. In clinical practice, physicians should be aware of these differences.