A Real-World Evaluation of Optical Coherence Tomography Angiography and Clinical Risk Factors for Mild Non-Proliferative Diabetic Retinopathy

Abstract

Objectives: To evaluate the clinical utility of optical coherence tomography angiography (OCTA) metrics for detecting mild non-proliferative diabetic retinopathy (NPDR) and to identify clinical risk factors associated with mild NPDR.

Methods: This prospective cross-sectional study included patients with type 2 diabetes mellitus (DM). OCTA metrics—including superficial and deep capillary plexus vessel densities (SVD and DVD), ganglion cell complex (GCC) thickness, and foveal avascular zone (FAZ) area—were measured in the parafoveal region using the Optovue Solix OCTA system. Logistic regression analysis adjusted for potential confounders was performed to evaluate associations between OCTA metrics, clinical risk factors, and mild NPDR.

Results: A total of 236 patients were enrolled, including 118 patients without DR and 118 with mild non-proliferative diabetic retinopathy (NPDR). SVD was significantly lower in the mild NPDR group compared to the no DR group (48.37 ± 2.25% vs. 49.22 ± 2.82%, p = 0.011), whereas other OCTA parameters showed no significant differences between groups. In adjusted logistic regression analyses, the presence of mild NPDR was significantly associated with SVD (p < 0.001), DVD (p = 0.003), and age (p = 0.001).

Conclusions: Although SVD was statistically reduced in patients with mild NPDR, the magnitude of difference was not clinically meaningful. Nonetheless, vessel density metrics and age were significantly associated with mild NPDR. While OCTA provides valuable quantitative assessment of retinal microvasculature, its utility as a routine screening tool for mild NPDR remains limited. Clinical fundoscopy continues to be the primary method for diagnosing mild NPDR.