Prevalence and risk factors for diabetic retinopathy: an Iranian eye study

PURPOSE. The aim of this study was to determine the prevalence of diabetic retinopathy among diabetic patients in Iran and its association with some predisposing factors. METHODS. All diabetic patients who attended the diabetes clinic underwent ocular examination, including slit-lamp biomicroscopy. The blood pressure and blood biochemical parameters were then measured. RESULTS. The prevalence of diabetic retinopathy among 1022 diabetic participants was 23.6% (241 cases). This study showed that there is a statistically significant relation between diabetic retinopathy and mean blood pressure, fasting blood sugar, blood urea nitrogen, and level of HbA(1)c. There was no difference in lipid profile between patients with and without retinopathy. The duration of diabetes was a predicting factor for retinopathy as well as presence of renal and cardiovascular diseases and fasting glucose >126 as independent variables. CONCLUSIONS. The duration of diabetes was the most important risk factor for progression of retinopathy.