Association of vitamin A and zinc with the development of diabetic retinopathy

Abstract

Introduction: Diabetic Retinopathy is a common microvascular disorder in people with diabetes mellitus. It is characterized by a variety of lesions within the retina and is the leading cause of blindness in adults. Hyperglycemia promotes the formation of reactive oxygen species and increased concentrations locally and throughout the body, even to the point of exceeding antioxidant capacity, a condition known as oxidative stress affecting retinal integrity. Antioxidants and trace elements are responsible for reducing oxidative damage. Vitamin A and Zinc have antioxidant properties. Objective: To evaluate vitamin A and Zinc levels in diabetic patients with and without diabetic retinopathy. Methods: Cross-sectional study was done in BIRDEM General Hospital and the CARS, University of Dhaka, from January 2021 to December 2021. Study parameters Fasting Blood Glucose, HbA1c, Vitamin A, and Zinc were estimated by standard laboratory methods. According to the inclusion criteria, 100 subjects over 30 years were included. They were divided into two groups; 50 were patients with diabetic retinopathy, and 50 were without diabetic retinopathy. After taking informed written consent, a structured questionnaire was filled up for each subject to collect data. Data were analyzed by independent student t-test, Chi-square test, and Pearson’s correlation test. Results: The study showed that vitamin A was significantly lower in patients with diabetic retinopathy (8.95±8.12) than in patients without diabetic retinopathy (22.39±11.56). Zinc level was also decreased in cases of group I (1.17±0.31) than in group II (1.43±3.60). Vitamin A had a significant negative correlation between FBG and HbA1c. But Zinc did not show a significant correlation with FBG and HbA1c. This study also found a significant positive correlation between vitamin A with Zinc. Conclusion: In this study, we found that vitamin A and zinc were significantly lower in patients with retinopathy than in patients without retinopathy.