Red cell distribution width obtained during blood cell count as a marker for renal function

Abstract

Red cell distribution width coefficient of variation (RDW-CV) has traditionally been used as an indicator of microcytic anemia, but its association with cardiovascular diseases has recently garnered attention. In this study, we investigated the potential of RDW-CV as a marker for kidney function screening. We analyzed 11,921 blood test records of individuals aged 18 and over that included cystatin C (CysC) measurements. Estimated glomerular filtration rates (eGFR) were derived from the blood test data and categorized based on the chronic kidney disease (CKD) guideline’s GFR classification. No clear trend was observed in the RDW-CV values when categorized by eGFR derived from serum creatinine. There was a trend of increasing RDW-CV values with declining kidney function in categories based on eGFRcys from CysC. The identification ability between the eGFRcys G1 + G2 group and G4 + G5 group yielded an area under the receiver operating characteristic curve of 0.681, with an odds ratio (95% confidence interval) of 1.27 (1.23–1.31). This odds ratio remained significant after adjusting for sex, age, serum creatinine, red blood cell count, hemoglobin concentration, and hematocrit values. These results conjection that RDW-CV is an independent factor for GFR classification progression. Our findings suggest the potential of RDW-CV as a renal function screening marker.