Relationship Between Retinal Capillary Nonperfusion Area and Renal Function in Patients With Type 2 Diabetes.

Purpose: We sought to assess the relationship between retinal nonperfusion area (NPA) on ultra-widefield fluorescein angiography (UWFA) and renal function in type 2 diabetes mellitus (DM) patients with diabetic retinopathy (DR) and nephropathy.

Methods: UWFA was performed in 248 eyes (124 patients) with DR, comprising 94 eyes from patients with chronic kidney disease (CKD) caused by diabetes and 154 eyes without CKD (non-CKD). Serum creatinine level (Cr), estimated glomerular filtration rate (eGFR), urine albumin/creatinine ratio (UACR), and urine protein/creatinine ratio (UPCR) were collected. On UWFA, retinal NPA was measured in an automated manner. The correlation between NPA and renal function was analyzed.

Results: The mean NPA value of the total eye was 33.11 ± 45.77-disc diameter (DA) in non-CKD and 100.57 ± 69.52 in CKD (P < 0.001). NPA of posterior pole was 1.21 ± 3.28 DA in non-CKD and 7.99 ± 6.75 in CKD group (P < 0.001). The NPA values of both the total eye and posterior pole were significantly correlated with Cr (r = 0.585 and 0.483), eGFR (r = -0.572 and -0.524), UACR (r = 0.541 and 0.482), and UPCR (r = 0.509 and 0.529, respectively) (all P ≤ 0.001). Linear modeling encompassing all clinical factors and relative clinical factors suggested eGFR as the most important predictor for NPAs of the total eye and posterior pole.

Conclusions: Larger retinal NPA on UWFA is associated with worse renal function in DM patients. Renal function can be used to predict retinal NPA in type 2 DM patients with nephropathy and DR.