[Epidemiology of diabetic retinopathy]

About 5% of total world population is affected by diabetes mellitus syndrome, with an expected increasing trend in the next years. Retinopathy, among the different diabetic complications, is the second cause (being cataract the first) of legal blindness in the industrialized countries. The range of results obtained from prevalence studies, mainly conducted in Anglo-saxon countries, varies from 5% to 70% in connection with the following risk factors: patient's age at the diagnosis date, duration of disease, metabolic control, arterial hypertension and lipidoproteinosis. Smoke and alcohol do not seem to be statistically relevant. The most probable mechanisms causing the retinopathy onset have been identified in the tissue hypoxia and in the vascular occlusion: the former is induced by the HA1c increase associated with hyperglycaemia; this is due to structural and hemorheologic alterations associated with diabetes syndrome. This study analysis the relations between diabetic retinopathy and beta-cellular reserve and cardio-vascular risk factors. 181 diabetics have been considered, subdivided into three groups: Type I diabetics and Type II diabetics and Type II diabetics (both without considering the duration of disease) and diabetics with over 10 years of disease. In each group the correlations between retinopathy severity and cardiovascular risk factors and beta-cellular reserve have been investigated. The results confirm that patient's age, duration of disease and metabolic control are statistically significant in relation to retinal lesion severity. The investigation on beta-cellular reserve, even though the results are not statistically significant, presents a trend towards lower values in more severe retinopathy.