Association of renal function with retinal vessel density in patients with type 2 diabetes by using swept-source optical coherence tomographic angiography
Wei Wang, Miao He, Xia Gong, Lanhua Wang, Jie Meng, Yuting Li, Kun Xiong, Wangting Li, Wenyong Huang
Abstract
AIMS: To investigate the relationship between retinal vessel density and renal function in patients with diabetes mellitus (DM) using non-invasive optical coherence tomographic angiography (OCTA). METHODS: This prospective cross-sectional study recruited ocular-treatment-naïve patients with DM registered in the community of Guangzhou, China. The retinal vessel density of the superficial capillary plexus in the macula was obtained by using swept-source OCTA imaging. The Xiangya equation was used to calculate the estimated glomerular filtrate rate (eGFR). Participants were divided into the following groups by eGFR: no chronic kidney disease (non-CKD), mild CKD and moderate-to-severe CKD (MS-CKD). RESULTS: A total of 874 patients with DM (874 eyes), with a mean age of 64.8±7.1 years, were included in the final analysis. The vessel density was significantly lower in patients with CKD than in non-CKD patients in a dose-response pattern, with a parafoveal vessel density of 49.1%±2.1% in non-CKD, 48.4%±1.9% in mild CKD and 47.2%±1.7% in MS-CKD (p<0.001). The sparser retinal capillaries were related to lower eGFR (β=0.037; 95% CI 0.025 to 0.049; p<0.001) and higher microalbuminuria (β = -0.023; 95% CI -0.039 to -0.008; p=0.002). The eGRF was independently associated with parafoveal vessel density (β=0.029; 95% CI 0.016 to 0.042; p<0.001), even after adjusting for other factors. CONCLUSION: Retinal vessel density decreased with renal function impairment, underlining the potential value of OCTA to detect early microvascular damage in the kidney in patients with diabetes.