504-P: Prevalence and Risk Factors of Diabetic Retinopathy in South Korea’s Population

Introduction & Objective: Diabetic retinopathy is a long-term microvascular complication of diabetes, and its prevalence has increased over recent years worldwide. The purpose of this study is to provide national representative statistics on the epidemiology and risk factors of diabetic retinopathy in Korean diabetic patients.

Methods: We conducted a cross-sectional study using the Korea National Health and Nutrition Examination Survey between 2017 and 2020. Participants aged ≥40 years who diagnosed with diabetes mellitus were analyzed. The prevalence of diabetic retinopathy during the entire period was estimated using the weighted percentage as mean and standard error. We also assessed adjusted risk factors for diabetic retinopathy using the logistic regression models.

Results: Among a total of 2,221 subjects (mean age, 60.8 years; 56.85% male subjects), 451 subjects had diabetic retinopathy, and the overall weighted prevalence of diabetic retinopathy was 20.64±1.06%. The prevalence of diabetic retinopathy tended to increase with higher HbA1c levels and longer duration of diabetes (P for trend <0.001). The adjusted odd ratios for incident diabetic retinopathy were 1.348 (95% CI 0.893-2.037), 2.012 (95% 1.385-2.922), 2.799 (95% CI 1.777-4.408), 3.406 (95% CI 1.971-5.886), and 5.85 (95% CI 3.273-10.457) for HbA1c levels of 6.5-6.9%, 7.0-7.9%, 8.0-8.9%, 9.0%-9.9% and ≥10.0%, respectively. And they were 1.499 (95% CI 0.992-2.267), 2.066 (95% 1.385-3.082), 20.396 (95% CI 1.542-3.724), and 3.622 (95% CI 2.386-5.498) for non-awareness, diabetes duration of <5 years, 5-10 years, 10-15 years, and ≥10 years, respectively.

Conclusion: The prevalence of diabetic retinopathy was estimated to increase in patients with poor control and long duration of diabetes. Hyperglycemia and diabetes duration are determinants for diabetic retinopathy in Korea's population.