Clinical factors related to the aqueous levels of vascular endothelial growth factor and hepatocyte growth factor in proliferative diabetic retinopathy

Abstract

Purpose. To investigate clinical factors related to the aqueous humor levels of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) in patients with proliferative diabetic retinopathy (PDR). Methods. Undiluted aqueous humor was obtained during ocular surgery from 46 eyes of 46 patients and the levels of growth factors were measured using enzyme-linked immunosorbent assays. VEGF and HGF levels were compared with the number of photocoagulation. VEGF and HGF levels in patient groups stratified according to the existence of vitreous hemorrhage, retinal detachment, and fibrovascular membrane were analyzed. And clinical parameters associated with the growth factors were determined by multiple regression analysis. Results. The levels of VEGF decreased significantly as the extent of photocoagulation increased and showed significant positive correlation with the existence of vitreous hemorrhage. There was no significant correlation between VEGF levels and the existence of fibrovascular membrane and traction retinal detachment. The levels of HGF also decreased significantly as the extent of photocoagulation increased, but increased significantly when fibrovascular membrane existed. There were no significant correlations between HGF levels and the existence of vitreous hemorrhage and traction retinal detachment. Concerning systemic conditions, each growth factor has no significant correlation with duration and type of diabetes mellitus, the treatment regimen, the control of hemoglobin A1C, and the existences of hypertension or renal dysfunction. Conclusion. The therapeutic effect of panretinal photocoagulation on PDR might be partly exerted by reduction of the levels of VEGF and HGF in ocular fluid. Since the clinical parameters associated with VEGF were different from those associated with HGF, these growth factors might influence the progression of retinopathy in different ways.