Association of macular microcirculation with renal function in Chinese non-diabetic patients with hypertension

The aim of this study was to investigate the association of macular microcirculation with renal function and the feasibility of using macular microcirculatory parameters to monitor renal function in Chinese non-diabetic patients with hypertension.

This case-control study included 62 non-diabetic patients with hypertension, including 31 with renal dysfunction (estimated glomerular filtration rate [eGFR] <90 mL/min/1.73 m²) and 31 with normal renal function (eGFR ≥90 mL/min/1.73 m²). Age, sex and clinic blood pressure were matched between groups. Macular microcirculatory parameters of 124 eyes of the 62 patients were evaluated by optical coherence tomography (OCT) and OCT angiography (OCTA).

In comparison with the patients with normal renal function, patients with renal dysfunction had lower macular superficial parafovea vessel density (18.6 vs. 19.4%, P = 0.029), macular cube average thickness (273.0 vs. 280.2 µm, P = 0.003), and average ganglion cell layer and inner plexiform layer (GCL-IPL) thickness (79.5 vs. 82.8 µm, P = 0.006), but similar macular central fovea vessel density and central fovea thickness (P ≥ 0.54). After adjustment for confounders, eGFR was significantly associated with macular superficial parafovea vessel density, cube average thickness and GCL-IPL thickness (P < 0.02). In detecting renal dysfunction, areas under the curve were 0.61, 0.66 and 0.65 for macular superficial parafovea vessel density, cube average thickness and GCL-IPL thickness.

In non-diabetic patients with hypertension, macular superficial parafovea vessel density, cube average thickness and GCL-IPL thickness were significantly worse in patients with renal dysfunction than those with normal renal function. Using macular parameters to monitor renal function is feasible.