A comparison between 2017 FAS and 2012 CKD-EPI equations: a multi-center validation study in Chinese adult population.

BACKGROUND

The recent guidelines recommend using the estimated glomerular filtration rate (eGFR) to evaluate renal function. There are two reported full-age-spectrum (FAS) equations in 2017, which are based on serum cystatin C concentrations with or without accompanying serum creatinine level (FAS or FAS). We compared the performance and assessed the applicability of the new FAS equation with the 2012 CKD-EPI (CKD-EPI and CKD-EPI) equation in Chinese subjects.

METHODS

A total of 1184 patients, mean aged 55.06 year who underwent Tc-DTPA GFR measurements (rGFR) from four hospitals were enrolled. The bias (eGFR-rGFR), precision (interquartile range of difference [IQR]), and accuracy (the proportion of eGFR within 30% of rGFR [P30]) of eGFR and rGFR calculated by four equations were compared.

RESULTS

Generally, the equation based on the combination of Cys and Scr performed superior to that on the basis of Cys alone, either the CKD-EPI or the FAS. Detailedly, referred to rGFR (67.33 ml/min/1.73 m), the CKD-EPI, CKD-EPI, FAS, and the FAS estimated GFR 56.46 ml/min/1.73 m, 62.79 ml/min/1.73 m, 56.45 ml/min/1.73 m, and 61.04 ml/min/1.73 m, gave ROC0.944, 0.954, 0.943, and 0.953, respectively. Another comparison as to bias, precision, P, and RMSE with FAS were - 2.87 ml/min/1.73 m, 19.01 ml/min/1.73 m, 74.16%, and 17.84 ml/min/1.73 m showed that FAS performed approximately more accurate than other equations, as well as the diagnostic consistency of GFR staging. In the rGFR < 60 ml/min/1.73 m subgroup, the FAS equation showed the best performance. In older subjects, compared with FAS, CKD-EPI, and CKD-EPI, the FAS equation had relatively less bias (- 8.09 vs. - 9.63, - 7.52, - 11.04, P < 0.05), most precise (15.18 vs. 16.32, 15.22, 16.63), and most accuracy, P was statistically different from the other equations, and achieved a ideal value > 70%.

CONCLUSION

The performance of the FAS equation is better than that of the CKD-EPI equation in the Chinese population, particularly in the elderly. Yet, further modification of FAS equations from a large-scale study could be more suitable for the Chinese population, particularly in older people.