Retinal Microcirculation Alterations in Microalbuminuric Diabetic Patients With and Without Retinopathy

To investigate the effect of microalbuminuria (MA) on superficial vessel density (SVD), deep vessel density (DVD), and choriocapillaris vessel density (CVD) in type-2 diabetic patients.

Twenty patients without diabetic retinopathy (DR) and MA (group 1), 20 patients without DR but with MA (group 2) and 30 patients with mild DR and MA (group 3) were enrolled in this prospective and cross-sectional study. SVD, DVD, and CVD of all patients were screened with optical coherence tomography angiography (OCTA). The relationships between these values and age, diabetes duration and metabolic parameters were also evaluated.

The whole macular SVD value was 50.15 ± 4.52 in group 1 and 47.81 ± 4.12 in group 2 (p = .04). The whole macular DVD value was 47.66 ± 2.76 in group 1, 44.37 ± 3.39 in group 3 (p = .02). Parafoveal DVD value was 52.58 ± 3.47 in group 1, 51.84 ± 2.23 in group 2, and 49.23 ± 3.38 in group 3 (p G1&3 = .001, p G2&3 = .02). Perifoveal DVD value was 47.92 ± 3.30 in group 1, 43.96 ± 4.19 in group 2, and 42.85 ± 2.98 in group 3 (p G1&2 = .02 and p G1&3 < .001). There were inverse correlations between diabetes duration, urea, creatinine, albumin, urinary sodium and some DVD values (p < .05, for all). Also, there were inverse correlations between parafoveal and perifoveal DVD values and MA (p = .002 and p = .031). Additionally, inverse correlations were determined between diabetes duration, creatinine, urea, serum Na and some CVD values (p < .05 for all).Conclusion: Decreased SVD and DVD values measured by OCTA in type-2 diabetic patients, whether they have mild DR or not, may be associated with MA causing early retinal microvascular changes.