Diabetic retinopathy and associated risk factors among volunteers with type 1 and 2 diabetes mellitus in the Upper Palatine of Bavaria

Background and objective: Diabetic retinopathy is the main cause of blindne ss in industrial countries. This study was undertaken to determine the prev alence of diabetic retinopathy and risk indicators among volunteers in a ru ral district in Bavaria, Germany. Patients and methods: Using a mobile survey unit, we investigated 627 diabe tic volunteers (275 women, 352 men, mean age 64,5 +/-12,5 yr) in 23 cities and villages. One retinal Polaroid photo was taken per eye, using a non-myd riatic camera (Canon CR4-45 NM). Results: In 60 subjects (9,6%) retinal photographs were not assessable. Amo ng the remaining 567 patients (76 Type 1-diabetes, HbA(1c) 7,3 +/- 1,2% and 491 Type 2-diabetes, HbA(1c) 7,7 +/- 1,5%) in 72,3% no retinopathy was fou nd (57,9% Type 1-diabetes/74,5% Type 2-diabetes). Non-proliferative retinop athy was diagnosed in 22% (38,2%/19,6) and proliferative retinopathy in 5,6 % (3,9%/5,9%). Photocoagulation scars were present in 6,1% (11.7%/5.3%) and macular oedema in 11.8% (14.1%/11.6%). In 6.1% (5.3%/6.6%) of patients vis ual acuity was less than 0.1 in at least one eye. The deg ree of retinopath y was found to be related to the duration of diabetes mellitus, age at onse t, glycaemic control (HbA(1c)), blood pressure and symptoms of neuropathy. Conclusions: The prevalence of retinopathy of 22,0% in the study group was found to be low for non-proliferative diabetic retinopathy, perhaps due to the methods used and/or good or acceptable glycaemic control measured as Hb A(1c).