Association between SGLT-2 inhibitor use and retinal microvascular parameters in patients with Type 2 diabetes mellitus: A cross-sectional study.

AIMS: Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) are widely used in Type 2 Diabetes Mellitus (T2DM) and may have neuroprotective and microvascular benefits. This study investigated SGLT-2i therapy effects on retinal microvasculature using optical coherence tomography angiography (OCTA) in T2DM patients. MATERIALS AND METHODS: This cross-sectional study included 100 T2DM patients (46 receiving SGLT-2i, 54 non-users). Patients underwent comprehensive evaluation, including OCTA. Central macular thickness (CMT), superficial capillary vascular density (SCVD), deep capillary vascular density (DCVD), and radial peripapillary capillary (RPC) density were measured. BMI and HbA1c were recorded. RESULTS: The SGLT-2i group had significantly higher weight and BMI (p < 0.01). Visual acuity and CMT did not differ between groups. However, non-users exhibited significantly higher DCVD in the whole retina, parafovea, and perifovea, and higher SCVD in the perifovea (p < 0.05). RPC densities in the inferior nasal and superior temporal regions were significantly higher in non-users (p < 0.05). CONCLUSION: SGLT-2i users showed lower retinal vessel densities compared to non-users. Due to the cross-sectional design, causality cannot be established; these results do not prove SGLT-2i adversely affects retinal microvasculature. Rather, these are hypothesis-generating observations. Prospective longitudinal studies are needed to clarify whether these findings reflect actual treatment effects or underlying patient characteristics.