Hubungan Red Cell Distribution Width (RDW) to Albumin Ratio (RAR) Terhadap Kejadian Nefropati Diabetik

Abstract

Background: The RDW-Albumin Ratio (RAR) is a marker that reflects systemic inflammation, oxidative stress, and nutritional status, so that a combination of the two can describe kidney damage in its early stages. The albumin-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) are the standard diagnostic tools for diabetic nephropathy, but they are less sensitive in the early stages, making RAR a potential biomarker for early detection, especially in non-albuminuric diabetic kidney disease (NA-DKD). Objective: To evaluate the association between the red cell distribution width-to-albumin ratio (RAR) and the incidence of diabetic nephropathy. Methods: This study is a prospective analytical study with a cross-sectional design conducted at Adam Malik Hospital from July to August 2025. A total of 66 patients with DMT2 who met the criteria were enrolled and underwent RDW examination using a Sysmex XN 1500 hemato analyzer based on erythrocyte histogram, and serum albumin was examined using the colorimetric test principle on the Cobas C 503 device, while RAR was obtained by calculating RDW/Alb. The research subjects were also examined for ACR, which was obtained from urine albumin examination using the immunoturbidimetric assay principle and urine creatinine using the colorimetric kinetic principle with the Cobas C 503 device. The examination results were analyzed using independent T-test and Mann Whitney statistics, Spearman's correlation test. Results: The diabetic nephropathy group demonstrated lower hemoglobin, serum albumin, and eGFR levels, as well as higher RDW, uric acid, creatinine, ACR, and RAR compared to the non-nephropathy group (p < 0.001). RAR showed significant positive correlations with uric acid (r = 0.373; p = 0.002), creatinine (r = 0.320; p = 0.009), and ACR (r = 0.754; p < 0.001), and a significant negative correlation with eGFR (r = –0.357; p = 0.003). Conclusion: RAR is significantly associated with ACR and other renal parameters, and may serve as an additional biomarker for the early detection of diabetic nephropathy.