Prevalence of and Factors Associated with Diabetic Retinopathy in Patients with Diabetes Mellitus at Siriraj Hospital - Thailand's Largest National Tertiary Referral Center

Purpose: We aimed to determine the prevalence of and factors associated with diabetic retinopathy (DR) in patients with diabetes mellitus (DM) and to evaluate the relationship between significant factors and severity of DR. Patients and Methods: A retrospective cross-sectional study of 1130 diabetic patients (mean age: 60 years, 62.7% female, 91% type 2 diabetes) was conducted in the diabetes clinic of Siriraj Hospital (Bangkok, Thailand) during January 2012 to June 2015. DR was graded as absent, mild, moderate, or severe non-proliferative DR, or proliferative DR. Multivariate logistic regression analysis was used to identify independent risk factors for DR in DM patients. Results: The overall prevalence of DR was 34.78%. Multivariate analysis revealed duration of diabetes, glycated hemoglobin level (HbA1c), presence of albuminuria, and abnormal protective sensation to be independent risk factors for DR. The prevalence of DR increased with longer duration of diabetes (p < 0.001), deterioration of glucose control (p = 0.006 for HbA1c), presence of significant albuminuria (p = 0.010), and loss of protective sensation (p = 0.001). Conclusion: In this study, one-third of DM were found to have DR. The independent predictors of DR were duration of diabetes, HbA1c level, presence of significant albuminuria, and impaired protective sensation. Heightened awareness of these risk factors will decrease the prevalence and severity of DR, and will improve early diagnosis and treatment of DR.