Retinopathy in type 2 diabetes mellitus is associated with increased intima-media thickness and endothelial dysfunction

Abstract

Background  Microangioathy and macroangiopathy in type 2 diabetes mellitus (T2DM) frequently coexist. Both types of vascular complications share traditional risk factors. It is not clear whether the presence of microangiopathy, such as diabetic retinopathy (DR), constitutes a predictor of atherosclerosis in T2DM. Here we described the search for the association between DR and intima-media thickness (IMT) in T2DM. We also compared endothelial function in subjects with and without DR. Material and methods  We examined 182 consecutive patients with T2DM for at least 5 years (mean age at examination 56·3 ± 6·52 years). We assessed (i) IMT of carotid artery by ultrasound and (ii) endothelial function by flow-mediated dilatation (FMD) method as well as by measurement of concentrations of von Willebrand factor (vWF) and s-ICAM-1. All patients underwent ophthalmological examination. Statistical analysis included Student's, Mann–Whitney, chi-square, Fisher tests and multiple regression. Results  DR was found in 71 (39·0%) subjects. IMT was higher in patients with DR than those without DR (0·87 mm vs. 0·79 mm, respectively, P = 0·0001). FMD was lower in the complication group than in subjects without DR (8·38% vs. 10·45%, respectively, P = 0·0023). Concentrations of s-ICAM-1 and vWF were not different between the groups. In multiple regression analysis, DR was among the predictors of increased IMT (P = 0·016) and decreased FMD (P = 0·002). We did not find a significant association of DR with vWF and s-ICAM-1 (P = 0·09 and P = 0·11, respectively). Conclusions  DR is associated with increased IMT and endothelial dysfunction in T2DM. Impaired endothelial function may be a common denominator of pathogenesis of microvascular complications and atherosclerosis in T2DM