Diabetic Retinopathy –Incidence And Risk Factors In A Community Setting- A Longitudinal Study

Aim: To evaluate the natural history of diabetic retinopathy (DR) in diabetic patients and to assess long term risk for other chronic diseases associated with DR. Methods: Retrospective, community-based study. Diabetics who underwent their first fundoscopic examination during 2000–2002, and had at least one follow- up examination by the end of 2007 were included. The primary outcome was the development of DR (proliferative diabetic retinopathy (PDR), non PDR (NPDR) or macular edema. Patients were followed for another 9 years for documentation of new diagnosis of related diseases. Results: 516 patients' (1,032 eyes) records were included and were followed first for an average of 4.15 ± 1.27 years. During follow-up, 28 (2.7%) of the total 1,032 eyes examined were diagnosed with PDR. An additional 194 (18.8%) eyes were diagnosed with new NPDR. The cumulative incidence of NPDR was 310/1,032 (30.0%). All the patients who developed PDR had prior NDPR. By the end of the 9 years extended follow up, patients with NPDR had a greater risk for developing chronic renal failure HR = 1.71 (1.14–2.56), ischemic heart disease HR = 1.57 (1.17–2.09), and had an increased mortality rate HR = 1.26 (1.02–1.57) Conclusion: DR is associated with a higher rate of diabetes complications. Patients with DR should be followed more closely.Key points During a mean follow-up of 4.5 years, the cumulative incidence of diabetic retinopathy in a community cohort was 18.8%. NDPR (non-proliferative diabetic retinopathy) is a predictor of PDR (proliferative diabetic retinopathy). In a real life setting NPDR is a marker of a poorer prognosis. Patients with NDPR should be monitored more closely.