Early Choroidal and Retinal Changes Detected by Swept-Source Oct in Type 2 Diabetes and Their Association with Diabetic Kidney Disease: A Longitudinal Prospective Study

Abstract

Background To evaluate structural changes in retina and choroid in patients with type 2 diabetes (T2D) and their association with diabetic kidney disease (DKD) Methods T2D patients with mild or no diabetic retinopathy (DR) were followed for 3 years using structural SS-OCT and OCT angiography (OCT-A) taken every 6 months. Parameters were compared longitudinally and according to the DKD status on baseline. Results One hundred and sixty eyes from 80 patients were followed for 3 years, 72 with no DKD (nDKD) at baseline and 88 with DKD. Trend analysis of T2D showed significant thinning in GCL + and circumpapillary retinal fiber neural layer (cRFNL), choroid, and decreased vascular density (VD) in superficial plexus and central choriocapillaris with foveal avascular zone (FAZ) enlargement. Patients with no DKD on baseline presented more significant declines in retinal center and choroidal thickness, increased FAZ and loss of nasal and temporal choriocapillaris volume. In addition, the nDKD group had worse glycemic control and renal parameters at the end of the study. Conclusion Our data suggest that early, progressive neurovascular damage occurs in the retina and choroid in T2D patients with no or mild DR. Glycemic control and renal damage parameters were associated to neurovascular damage progression.