Imbalance of Oxidant/Antioxidant Status and Risk Factors for Saudi Type 2 Diabetic Patients with Retinopathy
Yousef Aldebasi
Department of Optometry, College of Applied Medical Sciences, Qassim University, Saudi Arabia.
Abdelmarouf Mohieldein *
Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Saudi Arabia.
Yousef Almansour
Ophthalmology Department, King Fahad Specialist Hospital, Buraidah, Saudi Arabia.
Barakat Almoteri
Diabetes and Endocrinology Center, King Fahad Specialist Hospital, Buraidah, Saudi Arabia.
*Author to whom correspondence should be addressed.
Abstract
Aims: To estimate the oxidant/antioxidant status in type 2 diabetic patients with retinopathy; and to correlate a number of independent variables (age, gender, education, body mass index, duration of diabetes, glycosylated haemoglobin, hypertension) to development of retinopathy.
Study design: Case-control study.
Place and Duration of Study: Research laboratories, Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University from April 2010 to April 2011.
Methodology: One-hundred diabetic patients with retinopathy recruited from King Fahad Specialist Hospital- Buraidah were included in the study. The control groups were: control group 1 consisted of sixty type 2 diabetic patients without retinopathy recruited from Diabetes and Endocrinology Center, KFSH, Buraidah, KSA; and control group 2 consisted of sixty healthy "non diabetic subjects" recruited from public places, i.e. Estarahes (party lounges). Plasma, serum, and erythrocyte lysate were prepared from blood of each subject. Human serum 8-OHdG, plasma MDA, and erythrocyte lysate Cu-Zn SOD were estimated by using commercial kits supplied by Northwest, U.S.A. Data was analyzed using SPSS software and Win Episcope software. P- values < 0.05 were considered significant.
Results: Age, education, duration of diabetes, poor glycaemic control, and hypertension were consistently associated with development of retinopathy (OR 5.891, 4.44, 10.420, 1.699, 1.820 respectively). Moreover, increased plasma MDA, increased serum 8-OHdG levels, decreased Cu-Zn SOD activity were observed in diabetic patients with retinopathy compared to subjects in control groups. In addition, negative correlations were found between plasma MDA and Cu-Zn SOD activity, HbA1c & Cu-Zn SOD activity as well in all subjects.
Conclusion: This report emphasizes the important role of oxidative stress in the development of retinopathy in type 2 diabetes suggesting that blocking of oxidative stress is a crucial step for delayed progression of diabetic retinopathy and hence the need for antioxidant supplements to postpone the severity of diabetic retinopathy.
Keywords: Type 2 diabetes, diabetic retinopathy, risk factors, oxidative stress, malondialdehyde, 8-hydroxy-2`-deoxyguanosine, superoxide dismutase