Comparison of Vascular Endothelial Growth Factors (VEGFs) A and B with diabetic retinopathy severity and diabetic macular edema. Correlation between growth factors and anatomical parameters

Abstract

Purpose : Diabetic retinopathy (DR) affects a sizeable group of the population, leading to blindness, which can be reduced with proper monitoring and treatment. As the disease progresses from non-proliferative diabetic retinopathy (NPDR) to PDR, diabetic macular edema (DME) may occur at any stage. It was proven the increase of vascular endothelium growth factors (VEGFs) levels with disease stage, from NPDR to PDR, while DME appears to be independent of VEGF levels. This fact may lead ophthalmologists to opt for different initial treatments depending if patients are in an inflammatory or angiogenic stage. This study aimed to compare VEGF-A and VEGF-B levels with disease severity and the presence of DME and correlate VEGF levels with central retinal thickness (CRT) and macular volume (MV).

Methods : Vitreous samples were collected from 41 DR patients undergoing vitrectomy. VEGF-A and B were quantified by ELISA. Optical coherence tomography (OCT) was evaluated for CRT and MV.

Results : Forty-one patients with DR, 61% (n=25) male, with a mean age of 67.9±10.0 (mean±standard deviation). Mean vitreous VEGF-B levels were 18.13±22.10 pg/mL for NPDR and 115.70±278.42 pg/mL for PDR, with a statistically significant difference (p=0.004) showing higher values for PDR patients. VEGF-B was increased in DME (120.47±288.97 pg/mL) in comparison with non-DME (24.38±20.44 pg/mL), however, the difference was not statistically significant (p=0.204). Vitreous VEGF-A was significantly increased in PDR in comparison with NPDR, (576.88±681.15 vs 39.11±71.13 pg/mL, p=0.019, respectively). DME patients showed higher values of VEGF-A than non-DME, despite not statistically significant (456.10±651.84 vs 83.21±80.30 pg/mL, p=0.371, respectively). The correlation of NPDR with VEGF-B, CRT, and MV was not statistically significant, (r_sp=0.636, p>0.05), while was statistically significant in PDR (r_sp=0.590, p=0.008). The correlation of NPDR with VEGF-A, CRT, and MV was r_sp=-0.975, p=0.005 and with PDR was r_sp=0.590, p=0.008.

Conclusions : VEGF-A and B are increased in vitreous of DR patients and values increase with disease stage, while the absence of relation of VEGF-A and B with DME suggests VEGF levels may not be increased in all patients with DME. The strong correlations showed a simultaneous increase of VEGF levels with anatomical parameters.

This is a 2021 ARVO Annual Meeting abstract.