Optical Coherence Tomography Angiography Biomarkers in Thai Patients With Diabetic Nephropathy: A Diabetic Eye and Kidney Diseases (DEK-D) Study

PURPOSE: To identify optical coherence tomography angiography (OCTA) biomarkers to predict the diabetic nephropathy (DN) and their associations with 24-hour urine albumin levels in diabetic patients. METHODS: This cross-sectional, observational study examined 186 eyes from 93 individuals subdivided into three groups according to 24-hour urine albumin levels: no DN, early DN, and late DN. Vessel density (VD), fractal dimension, foveal avascular zone area, intercapillary area, central retinal thickness, and subfoveal choroidal thickness were measured from OCTA images to determine their association with the DN stages. RESULTS: VD values of the superficial capillary plexus, deep capillary plexus, and whole retina were significantly lower in the early DN group compared to the no DN group (adjusted P = 0.042, 0.016, and 0.008, respectively). VD values for the deep capillary plexus and whole retina were significantly decreased in the late DN group compared to the no DN group (adjusted P = 0.025 and 0.021, respectively). Mean fractal dimension, intercapillary area, foveal avascular zone area, central retinal thickness, and subfoveal choroidal thickness were not statistically different among the three groups. CONCLUSIONS: VD may be a useful parameter for the early non-invasive screening of DN. Further studies in larger populations are needed to establish a cutoff value for detection. TRANSLATIONAL RELEVANCE: This study investigated the association of each retinal vasculature measurement by OCTA and diabetic nephropathy status which could serve as an alternative way to screen for albuminuria.