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Abstract: TH-PO623

Comparison of Cardiovascular Event Predictability Between the 2009 CKD-EPI Equation and the New 2021 CKD-EPI Equations in a Korean CKD Cohort: From the KNOW-CKD Study

Session Information

Category: Hypertension and CVD

  • 1501 Hypertension and CVD: Epidemiology‚ Risk Factors‚ and Prevention


  • Kim, Ji Hye, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)
  • Oh, Kook-Hwan, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)

2009 CKD-EPI creatinine (Cr) equation is commonly used for estimated glomerular filtration rate (eGFR). However, it contains race component which is not a biological factor and may cause biased racism. Therefore, 2021 CKD-EPI Cr and creatinine-cystatin C (Cr-Cys) equations omitting race factor were introduced. This study evaluated if new 2021 equations have better predictability for cardiovascular events (CVE) and all-cause mortality in Korean chronic kidney disease (CKD) cohort.


This study included 2207 CKD patients enrolled in KoreaN Cohort Study for Outcome in Patients With Chronic Kidney Disease (KNOW-CKD). eGFR was calculated using 2009 Cr (eGFRCr), 2021 Cr and Cr-Cys (eGFRCr-Cys) equations. Receiver operating characteristic (ROC) and net reclassification improvement (NRI) were used to compare predictability of each CKD-EPI equation for CVE and CVE and all-cause mortality combined.


Overall prevalence of CVE and all-cause mortality were 9% and 7%. For CVE predictability, 10 mL/min/1.73m2 increase in eGFR was associated with lower odds only in unadjusted model in all three equations (2009 eGFRCr: HR 0.90, 95% CI [0.86, 0.95], 2021 eGFRCr: HR 0.91, 95% CI [0.87, 0.96], 2021 eGFR Cr-Cys: HR 0.90, 95% CI [0.85, 0.95]). For CVE and all-cause mortality combined, 10 mL/min/1.73m2 increase in eGFR was associated with lower odds in all three equations including multivariable model (2009 eGFR Cr: HR 0.93, 95% CI[0.89, 0.98], 2021 eGFRCr: HR 0.94, 95% CI[0.89, 0.98], 2021 eGFR Cr-Cys: HR 0.92, 95% CI[0.87, 0.96]). Area under curves of ROC for both CVE (0.715, 0.716, 0.716) and CVE and all-cause mortality combined (0.747, 0.747, 0.751) did not show significant differences among the three equations. Compared to 2009 equation, both 2021 Cr (NRI 0.013, 95% CI[-0.002, 0.028], p=0.09) and Cr-Cys (NRI -0.001, 95% CI[-0.031, 0.029], p=0.94) equations did not show improved CVE predictability. Similar findings were observed for CVE and all-cause mortality combined for both 2021 Cr (NRI -0.019, 95% CI[-0.039, 0], p=0.06) and Cr-Cys (NRI -0.002, 95% CI[-0.023, 0.018], p=0.82).


Neither 2021 CKD-EPI Cr, nor Cr-Cys equations showed significant improvement in predicting CVE and all-cause mortality in Korean CKD patients compared to 2009 CKD-EPI Cr equation.