Serum Apolipoprotein B and B/A1 Ratio as Early Negative Biomarkers for OCT- and OCTA-Detected Retinal Changes in Diabetic Macular Edema.

Purpose: This study aimed to explore the relationships between serum apolipoprotein A1 (ApoA1) and B (ApoB) levels and the ApoB/A1 ratio with structural and vascular changes in the retinas of patients with diabetic macular edema (DME), as assessed through optical coherence tomography (OCT) and OCT angiography (OCTA). Methods: 62 eyes from 38 treatment-naive diabetic retinopathy patients were assessed. Baseline and 6-month evaluations included clinical exams, fundus photography, blood tests for cholesterol, ApoA1, and ApoB, as well as imaging with OCT and OCTA. Associations between apolipoproteins and changes in central retinal thickness (CRT), foveal avascular zone (FAZ), and vessel/perfusion density were analyzed. Results: In DME patients, elevated ApoB levels (>122.5 mg/dL) were significantly linked with increased CRT, FAZ expansion, and reduced perfusion density at the 6-month follow-up (p = 0.026, 0.046, and 0.025). Higher ApoB/A1 ratio (>0.85) was significantly associated with decreased perfusion density (p = 0.011). Conclusion: Elevated ApoB levels and ApoB/A1 ratio were linked with reduced perfusion and vessel density, increased CRT, and FAZ expansion, highlighting their potential as negative biomarkers for OCT-detected retinomacular changes.