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Teo BW, Koh YY, Toh QC, Li J, Sinha AK, Shuter B, Sethi S, Lee EJ
Correspondence: Dr Teo Boon Wee, email@example.com
INTRODUCTION Clinical practice guidelines recommend using creatinine-based equations to estimate glomerular filtration rates (GFRs). While these equations were formulated for Caucasian-American populations and have adjustment coefficients for African-American populations, they are not validated for other ethnicities. The Chronic Kidney Disease-Epidemiology Collaborative Group (CKD-EPI) recently developed a new equation that uses both creatinine and cystatin C. We aimed to assess the accuracy of this equation in estimating the GFRs of participants (healthy and with chronic kidney disease [CKD]) from a multiethnic Asian population.
METHODS Serum samples from the Asian Kidney Disease Study and the Singapore Kidney Function Study were used. GFR was measured using plasma clearance of 99mTc-DTPA. GFR was estimated using the CKD-EPI equations. The performance of GFR estimation equations were examined using median and interquartile range values, and the percentage difference from the measured GFR.
RESULTS The study comprised 335 participants (69.3% with CKD; 38.5% Chinese, 29.6% Malays, 23.6% Indians, 8.3% others), with a mean age of 53.5 ± 15.1 years. Mean standardised serum creatinine was 127 ± 86 μmol/L, while mean standardised serum cystatin C and mean measured GFR were 1.43 ± 0.74 mg/L and 67 ± 33 mL/min/1.73 m2, respectively. The creatinine-cystatin C CKD-EPI equation performed the best, with an estimated GFR of 67 ± 35 mL/min/1.73 m2.
CONCLUSION The new creatinine-cystatin C equation estimated GFR with little bias, and had increased precision and accuracy in our multiethnic Asian population. This two-biomarker equation may increase the accuracy of population studies on CKD, without the need to consider ethnicity.
Keywords: Asian, chronic kidney disease, creatinine, cystatin C, glomerular filtration rate
Singapore Med J 2014; 55(12): 656-659; http://dx.doi.org/10.11622/smedj.2014181
| 1. Rule AD, Teo BW. GFR estimation in Japan and China: what accounts for the difference? Am J Kidney Dis 2009; 53:932-5. |
| 2. Inker LA, Schmid CH, Tighiouart H, et al. Estimating glomerular filtration rate from serum creatinine and cystatin C. N Engl J Med 2012; 367:20-9. |
| 3. Teo BW, Xu H, Wang D, et al. GFR estimating equations in a multiethnic Asian population. Am J Kidney Dis 2011; 58:56-63. |
| 4. Teo BW, Xu H, Wang D, et al. Estimating glomerular filtration rates by use of both cystatin C and standardized serum creatinine avoids ethnicity coefficients in Asian patients with chronic kidney disease. Clin Chem 2012; 58:450-7. |
| 5. Teo BW, Xu H, Koh YY, et al. Estimating kidney function in a multiethnic Asian population with multiple filtration markers. Am J Kidney Dis 2012; 60:500-2. |
| 6. Teo BW, Xu H, Koh YY, et al. Glomerular filtration rates in healthy Asians without kidney disease. Nephrology (Carlton) 2014; 19:72-9. |
| 7. Fleming JS, Zivanovic MA, Blake GM, Burniston M, Cosgriff PS. Guidelines for the measurement of glomerular filtration rate using plasma sampling. Nucl Med Commun 2004; 25:759-69. |
| 8. Bröchner-Mortensen J. A simple method for the determination of glomerular filtration rate. Scand J Clin Lab Invest 1972; 30:271-4. |
| 9. Du Bois D, Du Bois EF. A formula to estimate the approximate surface area if height and weight be known. 1916. Nutrition 1989; 5:303-11. |
| 10. Larsson A, Hansson LO, Flodin M, Katz R, Shlipak MG. Calibration of the Siemens cystatin C immunoassay has changed over time. Clin Chem 2011; 57:777-8. |
| 11. Voskoboev NV, Larson TS, Rule AD, Lieske JC. Importance of cystatin C assay standardization. Clin Chem 2011; 57:1209-11. |
| 12. Inker LA, Eckfeldt J, Levey AS, et al. Expressing the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) cystatin C equations for estimating GFR with standardized serum cystatin C values. Am J Kidney Dis 2011; 58:682-4. |
| 13. Herget-Rosenthal S, Bökenkamp A, Hofmann W. How to estimate GFR-serum creatinine, serum cystatin C or equations? Clin Biochem 2007; 40:153-61. |
| 14. Rule AD, Larson TS, Bergstralh EJ, et al. Using serum creatinine to estimate glomerular filtration rate: accuracy in good health and in chronic kidney disease. Ann Intern Med 2004; 141:929-37. |
| 15. Zuo L, Ma YC, Zhou YH, et al. Application of GFR-estimating equations in Chinese patients with chronic kidney disease. Am J Kidney Dis 2005; 45:463-72. |
| 16. Ma YC, Zuo L, Chen JH, et al. Modified glomerular filtration rate estimating equation for Chinese patients with chronic kidney disease. J Am Soc Nephrol 2006; 17:2937-44. |
| 17. Matsuo S, Imai E, Horio M, et al. Revised equations for estimated GFR from serum creatinine in Japan. Am J Kidney Dis 2009; 53:982-92. |
| 18. Teo BW, Ng ZY, Li J, et al. The choice of estimating equations for glomerular filtration rate significantly affects the prevalence of chronic kidney disease in a multi-ethnic population during health screening. Nephrology (Carlton) 2009; 14:588-96. |
| 19. Praditpornsilpa K, Townamchai N, Chaiwatanarat T, et al. The need for robust validation for MDRD-based glomerular filtration rate estimation in various CKD populations. Nephrol Dial Transplant 2011; 26:2780-5. |