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Abstract: SA-PO923

Clinical Significance of Serum Creatinine-to-Cystatin C Ratio on Renal Outcomes in Non-Dialysis-Dependent CKD Patients: Results From the KNOW CKD Study

Session Information

Category: CKD (Non-Dialysis)

  • 2202 CKD (Non-Dialysis): Clinical‚ Outcomes‚ and Trials


  • Kang, Donghyuk, Korea University College of Medicine and School of Medicine, Seoul, Korea (the Republic of)
  • Kim, Yaeni, Catholic University of Korea School of Medicine, Seoul, Korea (the Republic of)

Sarcopenia is prevalent in CKD patients and is associated with poor clinical outcomes. The assessment of skeletal muscle mass and strength may help in decision-making in patient care, but it is difficult to perform. Recently, the serum creatinine-to-cystatin C ratio has been proposed as a surrogate marker for detecting muscle wasting. We aimed to evaluate the impact of the creatinine-to-cystatin C ratio on renal outcomes in non-dialysis-dependent CKD patients.


In this observational Korean Cohort Study for Outcome in Patients with CKD (KNOW-CKD), 1,452 patients with CKD stages 1-3 were analyzed. Men and women were separately categorized into quartile groups according to their creatinine-to-cystatin C ratio. The primary outcome was a composite of renal outcome consisting of a 50% reduction in estimated glomerular filtration rate (eGFR) or initiation of renal replacement therapy, whichever occurred first. Using Cox regression analysis, the association between the creatinine-to-cystatin C ratio and the primary outcome was analyzed.


During a median follow-up of 6.0 (4.3-7.8) years, the primary composite renal outcome occurred in 325 (22%) patients within a median of 4.0 (2.8-5.8) years. After sequential adjustment with 15 variables in the fully adjusted Cox regression model, lower creatinine-to-cystatin C ratio groups (quartiles 1 and 2) had a poor primary outcome compared to the highest group (quartile 4); the hazard ratios for quartiles 1, 2, and 3 compared with quartile 4 were 2.41 (95% confidence interval [CI], 1.61-3.60), 1.93 (95% CI, 1.37-2.72), and 1.40 (95% CI, 0.98-2.01), respectively.


Serum creatinine-to-cystatin C ratio is an independent predictor of renal outcomes. A low creatinine-to-cystatin C ratio is associated with poor renal outcome.