Estimation of the level of glycosylated hemoglobin as a predictor factor to bevacizumab injection in diabetic macular edema in a sample of iraqi patients

Abstract

BACKGROUND: Clinically significant macular edema consider as one of the most critical complications of poorly controlled diabetes and its the main reason of decreased vision in that kind of patients. AIM: We try in this article to find the relation between glycosylated hemoglobin (HbA1C) level and the response to bevacizumab injections in people with macular edema. MATERIALS AND METHODS: Ninety-five patients (55 male: 40 female) were recruited in this study, all of them had diabetes type 2, age of the participants ranging from 42 to 70 years old, Complete ophthalmic examination was done for all the participants including (best-corrected visual acuity [VA]), (intraocular pressure) checking, fundus evaluation, and central macular thickness measurement, serum HbA1C was also measured, Patients were given 0.05 ml (1.25 mg) of bevacizumab (Avastin) intravitreally for 3 successive months, Follow up visit was at 4, 8, 12 week post-injection. On each follow-up detailed examination was done including The (best-corrected VA) examination, (Intraocular pressure), both fundus examination, and optical coherence tomography (OCT) of the macula. RESULTS: This study included 111 patients who had type 2 diabetes mellitus who were classified according to HbA1c into two sub-groups, HbA1c ≤7% (n = 45) and HbA1c >7% (n = 66) we found no significant difference in mean age and frequency distribution according to gender between study groups (p > 0.05), but, there was a highly significant difference in mean HbA1c % (p < 0.001). when we compare mean OCT and mean VA before and after the intervention in patients who had diabetes mellitus classified according to HbA1c into (HbA1c ≤7% and HbA1c >7%) we found that before the intervention, there was no significant difference in mean OCT between study groups (p > 0.05), but after the intervention, there was a reduction in mean OCT and the reduction was more pronounced in the group of HbA1c of <7% (p < 0.001). About VA, we found no significant difference before the intervention and after the intervention the changes were comparable between both study groups (p > 0.05). CONCLUSION: Intra-vitreal injections of bevacizumab result in anatomical (macular thickness) and functional (vision) improvement in those patients who had diabetic macular edema and strict glycemic control affecting the outcome of the treatment where strict regulation of glucose level have yield maximum benefit from the given therapy.