#2158 Circulating kidney injury molecule-1 a valuable marker of mortality in hemodialysis patients?

Abstract

Abstract Background and Aims The importance of finding reliable biomarkers of mortality in CKD, and especially in patients treated with hemodialysis has become evident. Plasma KIM-1 has been mentioned as a marker of cardiovascular morbidity.. The aim of this study is to assess the level of plasma Kidney Injury Molecule- 1 (KIM-1) as a marker of mortality in patients treated with hemodialysis. Method We conducted a single-center study that included 63 CKD G5D patients (hemodialysis for 1-5 years) followed up for 48 months and a control group consisting of 52 patients diagnosed with CKD stages G1-G5, without HfrEF. All patients have been assessed at baseline, regarding cardiovascular disease (medical history, echocardiography and ECG). Circulating plasma KIM-1 levels were determined with single molecule counting immunoassay technology using the Enzyme-linked immunosorbent assay, we performed using standard methods blood biochemistry, and markers of inflammation (CRP, IL-6) and markers of anemia (complete blood count, serum ferritin, transferrin saturation- TSAT). Results Mean plasma KIM1 levels were 403.8 +/-546.8pg/ml) in the group of patients treated with hemodialysis, and was statistically significantly higher compared to the level in the control group (217.48 +/-267.10 pg/ml). In the group of patients treated with hemodialysis plasma KIM-1 levels showed a statistically significant correlation with inflammation (mean CRP- R=0.28, p=0.02 and IL6- R=0.36, p=0.005) and with anemia (hematocrit- R= -0.5, p=-0,0316; hemoglobin - R= -0.5, p=0.02 We found out using ANOVA that patients which presented left ventricular hypertrophy on echocardiography (37 out of 62) had significantly lower mean levels of plasma KIM-1 (155,51 vs 432,12 pg/ml; p=0,026). The group of patients with vascular calcifications on echocardiography (48 out of 62) had lower levels of serum KIM1 (210.01 vs 462.58 pg/ml, p=0.04). After 24 months of follow up we found a mortality rate of 22.23%, while after 48 months the mortality rate was of 50.73%. Using a Cox proportion-hazards regression analysis of predicting factors of mortality we found that regarding the relationship between plasma levels of KIM-1 and mortality there is a significantly decreased survival in patients with low KIM-1<81.98 pg/ml (p<0.001), with a cut-off point for plasma KIM-1 levels= 81.98 pg/ml. Conclusion Plasma KIM-1 levels were significantly higher in patients treated with hemodialysis compared to the control group (ND CKD patients). However, surprisingly, low levels of plasma KIM1 were associated with some cardiovascular changes and also to an increased risk of mortality (at 4 years, not after few months).