The Effect of a Systemic Angiotensin Receptor Blocker on Vascular Endothelial Growth Factor in the Vitreous of Patients with Proliferative Diabetic Retinopathy

Abstract

Purpose: Renin-angiotensin system (RAS) is reportedly associated with the vitreous level of vascular endothelial growth factor (VEGF) in proliferative diabetic retinopathy (PDR). This study was conducted to investigate the effect of systemic angiotensin receptor blocker (ARB) on vitreous VEGF in PDR.Method: Patients who underwent a vitrectomy due to PDR were divided into two groups: patients who were taking ARB to control hypertension (Group A) and normotensive patients (Group B). Patients having epiretinal membrane or macular hole without diabetes or hypertension were included in the control group (Group C). We assessed the best-corrected visual acuity (BCVA) and VEGF levels of the vitreous fluid and the serum using enzyme-linked immunosorbent assay.Results: Nineteen eyes were in Group A, 27 eyes in Group B, and 30 eyes in Group C. The mean levels of vitreous VEGF were 487.5 pg/ml in Group A and 553.0 pg/ml in Group B. In Group C, the vitreous VEGF was below the detection limit in 29 of the 30 eyes. The mean serum VEGF levels were 384.8 pg/ml, 384.6 pg/ml, and 388.1 pg/ml, respectively. The ratio of vitreous VEGF to serum was 4.0 in Group A and 2.97 in Group B. There were no differences in vitreous and serum VEGF levels between two groups. The median BCVA of Groups A and B significantly improved from 1.55 and 1.10 at baseline to 0.55 and 0.30 respectively at 6 months (logarithm of minimal angle resolution, p < 0.005). No differences were found in visual acuity.Conclusion: Systemic ARB did not show beneficial effects with respect to the vitreous level of VEGF or functional outcomes after vitrectomy in patients with PDR.