study of four year incidence rate of diabetic retinopathy and its associated factors in type ii diabetese patients

introduction: it seems that improvement in care and new treatment and screening methods along with better control of diabetes mellitus (dm) has led to a change in incidence of diabetic complications, especially diabetic retinopathy .this study was performed to assess the 4 years incidence rate of diabetic retinopathy in patients with type ii diabetes and factors affecting its progression. methods: in this prospective study on diabetic patients referring to yazd diabetes center, 120 type ii diabetic patients without diabetic retinopathy were selected. after complete ophthalmic examination, fasting blood sugar (fbs), post prandial blood sugar, triglyceride and cholesterol levels were measured, and height, weight and blood pressure (bp) were recorded. then the patients were followed with yearly eye examinations for 4 years. results: four year cumulative incidence of diabetic retinopathy was 47.5% (95%ci: 38.6 – 56.4). the retinopathy was mild, non proliferative diabetic retinopathy (npdr) in 43 (35.8%) where as 10(8.3%) patients had moderate npdr and 3(2.5%) patients had severe npdr. only one patient had proliferative diabetic retinopathy. the incidence of diabetic retinopathy was 5.8% in first year, 20.3% in second year, 24.4%in third year and 7.4% in fourth year. duration of diabetes, fbs and systolic bp had a statistically significant relationship with grades of diabetic retinopathy, but there was no significant association between age, sex, body mass index (bmi) , triglyceride and cholesterol levels, method of treatment, smoking and diastolic bp with grades of diabetic retinopathy. conclusion: duration of diabetes, blood glucose levels and systolic blood pressure are main risk factors of diabetic retinopathy.