Session Title: Free Paper Session 19: Vascular Diseases & Diabetic Retinopathy V
Session Date/Time: Saturday 09/09/2017 | 16:30-18:00
Paper Time: 17:42
Venue: Room 120
First Author: : A.Victor INDONESIA
Co Author(s): : T. Gondhowiardjo R. Dharma S. Jusman V. Yandri R. Yuneta R. Yuriza
To identify the level of hypoxia-induced factor-1α (HIF-1α) in proliferative diabetic retinopathy (PDR) patients treated by laser photocoagulation (LP) and intravitreal bevacizumab (IVB)
Department of Ophthalmology, Faculty of Medicine, University of Indonesia, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
This was a cross sectional study of patients with PDR treated with laser photocoagulation or IVB in Cipto Mangunkusumo Hospital, Jakarta, Indonesia. The samples were consecutively collected from June 2015 to August 2016. This study received approval by Ethics Committee, and informed written consent was obtained from all participants. The inclusion criteria were as follows: 1) Type II diabetic with PDR who fulfilled the requirement of vitrectomy; 2) PDR patients who agreed to follow each step of the study and signed the informed consent. The exclusion criteria included uncontrolled hypertension, congestive heart failure, stroke history, impaired renal function, collagen vascular diseases (rheumatoid arthritis, systemic lupus erythematous, systemic sclerotic), hemostatic disorders or consuming anticoagulant drugs. The samples were undiluted vitreous fluid (0.5-1.0) ml harvested from the eligible subjects by pars plana vitrectomy. HIF-1α level was measured by using enzyme-linked immunosorbent assay (ELISA). The level of HIF-1α in each group of treatment were compared and analyzed by Kruskal-Wallis test.
A total of 70 patients (34 patients without LP/IVB treatment, 11 with single-session LP (sLP), 11 with multiple-session LP (mLP), and 14 with IVB), were eligible for this study. Patients who did not experience LP/IVB treatment, served as the control group. In this study, there were 46 (65.7%) female and 24 (34,3%) male patients with a mean age of 48 years. There was no significant difference in HIF-1α level between patients who suffered from diabetes type II for under 10 years (0.017 ng/mL [0.003-4.668]) or longer (0.0165 ng/mL [0.006-0.077]). Patients with uncontrolled diabetes mellitus reached the highest median concentration of HIF-1α among other groups (0.17 ng/mL [0.003-0.210]; p=0.94). Nevertheless, the level of HIF-1α had no significant correlation with the glycemic control status (p=0.94). On the other hand, there was a significant correlation of HIF-1α level with all treatment groups (p = 0.02). Higher HIF-1α level was found in the IVB group (0.033 ng/mL [0.016-4.668]). While, the level of HIF-1α of both LP groups was similar with the control group.
HIF-1α has been known to have a correlation with disease progression in diabetic retinopathy, by up-regulating vascular endothelial cell growth factor (VEGF). Compared with the control group, the high concentration of intravitreous HIF-1α in IVB group suggests that IVB 1-2 week prior to vitrectomy may not have direct effect in decreasing the level of HIF-1α in PDR patients. We also assumed that both laser groups had less effect in reducing HIF-1α concentration due to the low number of laser spots. However, further studies using higher number of laser spots and larger sample size, are needed to support this conclusion.