Environmental and dietary factors affecting the progression of type 2 diabetic retinopathy in Aljabal Algharby, Libya

Abstract

The purpose of the paper is to study the role of some Environmental and Dietary Factors affecting the progression of Type 2 Diabetic Retinopathy in Aljabal Algharby, Libya. A prospective non-comparative study was conducted from September 2012 to July 2013 at the Ophthalmology Department in Gharian Central Teaching hospital, Gharian, Aljabal Algharbi, Libya. Thirty cases with medical history of uncontrolled Type 2 diabetes lasting more than 10 years and no other systemic diseases were collected. Complete ophthalmic clinical examination including dilated fundus examination and laboratory investigations as Random Blood Glucose (RBG) level and Glycosylated Hemoglobin (HgA1c) besides Complete Blood Count (CBC) were carried out to all cases. The cohort included 30 cases 15 males (50%) and 15 females (50%). Their mean age was 55.29 ± 2.46 years (range, 48 years to 66 years: males; 53.39 ± 3.03 years and females; 56.67 ± 3.75 years). The duration of Type 2 diabetes mellitus ranged from 10 years up to 16 years with a mean 13.17 ± 2.16 years. All the cases were diagnosed with either normal or mild non-prolifrative stage of diabetic retinopathy. Thirty cases (100%) were having Random Blood Glucose (RBG) above 200 mg/ml and +ve Glycosylated Hemoglobin (HgA1c) results above 7% indicating the uncontrolled state of diabetes. Twenty six cases (86.7%) gave a history of regular intake of Virgin Olive Oil (VOO) in their diet. Twenty three cases (76.7%) had Secondary Polycythemia with a mean Red Blood Cells (RBC) Count 6.2 ± 0.5 million cells/mcL associated with a mean Hemoglobin (Hg) level 13.73 ± 1.32 g/dl in their blood picture which correlated with history of prolonged living at high altitude. In conclusion, the regular dietary intake of Virgin Olive Oil (VOO) which is a main component of the Mediterranean diet was proved to have a beneficial effect on the reduction of progression of type 2 diabetic retinopathy. On the other hand, the prolonged hypoxia exposure and associated Secondary Polycithemia may play a role in a process of tissue adaptation that results in a lower tissue response to the ischemic state responsible for type 2 diabetic retinopathy.

Keywords: Type 2 diabetic retinopathy, prolonged hypoxia, virgin olive oil.