Association of Carotid Intima-Media Thickness and Arterial Stiffness With Diabetic Retinopathy

Abstract

OBJECTIVE—The aim of this study was to assess the association of intima-media thickness (IMT) and arterial stiffness with diabetic retinopathy in an Asian-Indian population that has very high prevalence rates of diabetes and coronary artery disease. RESEARCH DESIGN AND METHODS—The study was conducted on 600 type 2 diabetic subjects randomly selected from the Chennai Urban Rural Epidemiology Study (CURES), which is an ongoing population-based study of a representative population of Chennai. When present, retinopathy was graded according to a modified Early Treatment Diabetic Retinopathy Study grading system. IMT was determined using high-resolution B-mode ultrasonography. Arterial stiffness was measured by assessing the augmentation index (AI) using the Sphygmocor apparatus. RESULTS—Retinopathy was diagnosed in 116 of 590 (19.6%) subjects in whom retinal photography was possible. Mean values of IMT (0.93 ± 0.36 vs. 0.85 ± 0.21 mm, P = 0.001) and AI (27.9 ± 8.9 vs. 25.8 ± 9.6%, P = 0.031) were significantly higher among diabetic subjects with retinopathy compared with those without. Both IMT (P = 0.024) and AI (P = 0.050) showed a significant association to diabetic retinopathy, even after adjusting for age, duration of diabetes, HbA1c, serum cholesterol, serum triglycerides, and microalbuminuria. CONCLUSIONS—Diabetic retinopathy is associated with IMT and AI, suggesting that common pathogenic mechanisms might predispose to diabetic micro- and macroangiopathy.