#4609 ASSOCIATION BETWEEN THE SERUM CREATININE-TO-CYSTATIN-C RATIO AND RAPID PROGRESSION OF CHRONIC KIDNEY DISEASE

Abstract

Abstract Background and Aims Chronic Kidney Disease (CKD) is a common and progressive condition that affects a significant portion of the global population. It is a leading cause of death and requires timely evaluation and monitoring to ensure proper management. Cystatin C has been shown to be an effective marker of kidney function and a predictive marker of CKD progression. However, there is limited research evaluating the relationship between the serum creatinine-to-cystatin-C (Cr/cysC) ratio and the rapid progression of CKD. This study aims to investigate the effectiveness of the Cr/cysC ratio in predicting rapid progression of CKD. Method A retrospective study was conducted on 1,104 patients with CKD who were treated at the Nephrology Outpatient Clinic of Hanyang University Guri Hospital between December 2020 and November 2022. Eligible patients had at least two simultaneous measurements of serum creatinine and cystatin C, with a minimum interval of 6 months. The definition of rapid progression of CKD was a decrease in creatinine-based estimated glomerular filtration rate (eGFR) of more than 4 mL/min/1.73 m2 over a 1-year period or initiation of renal replacement therapy (RRT). In addition, considering the short duration of the study, initiation of RRT was considered as a secondary outcome only in CKD stages 3b, 4, and 5. Results The study population consisted of patients with CKD stages 1 to 5, with a mean age of 69.7 years and 57.7% of the population being male. The mean baseline body mass index was 25.8 kg/ m2, and the mean initial eGFR was 46.7 mL/min/1.73 m2. 38.4% of the total patients showed rapid progression of CKD. The analysis showed that a lower Cr/cysC ratio was significantly associated with an increased risk of rapid progression of CKD (OR: 0.812, 95% CI: 0.761-0.867, p<0.001). After adjusting for age, sex, body mass index, and initial eGFR, a lower Cr/cysC ratio remained a significant risk factor for rapid progression of CKD (OR: 0.760, 95% CI: 0.685-0.844, p<0.001). The initiation of RRT increased with the advancement of CKD stage, with 11 patients with CKD stage 3b, 30 patients with CKD stage 4, and 41 patients with CKD stage 5 initiating dialysis treatment. After adjusting for all variables, the OR was 0.774 (95% CI: 0.667-0.898, p = 0.001), indicating that as the Cr/cysC ratio increased, the progression of dialysis significantly decreased by 22.6%. Conclusion In this study, a lower Cr/cysC ratio was significantly associated with an increased risk of rapid progression of CKD and initiation of RRT. The results of this study suggest that monitoring the Cr/cysC ratio may provide valuable information for the management of CKD patients.