A new equation to estimate glomerular filtration rate in Chinese elderly population.
BACKGROUND
We sought to develop a new equation to estimate glomerular filtration rate (GFR) in Chinese elderly population.


METHODS
A total of 668 Chinese elderly participants, including the development cohort (n = 433), the validation cohort (n = 235) were enrolled. The new equation using the generalized additive model, and age, gender, serum creatinine as predictor variables was developed and the performances was compared with the CKD-EPI equation.


RESULTS
In the validation data set, both bias and precision were improved with the new equation, as compared with the CKD-EPI equation (median difference, -1.5 ml/min/1.73 m(2) vs. 7.4 ml/min/1.73 m(2) for the new equation and the CKD-EPI equation, [P<0.001]; interquartile range [IQR] for the difference, 16.2 ml/min/1.73 m(2) vs. 19.0 ml/min/1.73 m(2) [P<0.001]), as were accuracies (15% accuracy, 40.4% vs. 30.6% [P = 0.02]; 30% accuracy, 71.1% vs. 47.2%, [P<0.001]; 50% accuracy, 90.2% vs. 75.7%, [P<0.001]), allowing improvement in GFR categorization (GFR category misclassification rate, 37.4% vs. 53.2% [P = <0.001]).


CONCLUSIONS
A new equation was developed in Chinese elderly population. In the validation data set, the new equation performed better than the original CKD-EPI equation. The new equation needs further external validations. Calibration of the GFR referent standard to a more accurate one should be an useful way to improve the performance of GFR estimating equations.
Division of Nephrology, Department of Internal Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China ; College of Biomedical Engineering, South China University of Technology, Guangzhou, China.
Xun
X
Liu
Yanni
Y
Wang
Cheng
C
Wang
Chenggang
C
Shi
Cailian
C
Cheng
Jinxia
J
Chen
Huijuan
H
Ma
Linsheng
L
Lv
Lin
L
Li
Tanqi
T
Lou
D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D002681:China; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology*; D015203:Reproducibility of Results