Diabetes Research and Clinical Practice 65 (2004) 13–19 Flow mediated dilatation and carotid intimal media thickness in South Indian type 2 diabetic subjects B. Mamtha Nair, Vijay Viswanathan ∗ , C. Snehalatha, R. Suresh Mohan, A. Ramachandran Diabetes Research Centre, WHO Collaborating Centre for Research, Education and Training in Diabetes, No. 4 Main Road, Royapuram, Chennai 600 013, India Received in revised form 12 November 2003; accepted 14 November 2003 Abstract Objective: The aims of this study were to determine: (1) endothelial function in type 2 diabetic subjects with and without diabetic microvascular complications using flow mediated dilatation method (FMD); (2) influence of other variables on FMD; and (3) the correlation between FMD and carotid intimal media thickness (IMT). Research, Design and Methods: In this cross-sectional study, flow mediated dilatation (FMD) and intimal media thickness (IMT) were determined using high resolution ultrasonography in 20 non-diabetic subjects, in 23 type 2 diabetic subjects without any complications and in 23 type 2 diabetic patients with nephropathy and retinopathy. Results: Age-adjusted mean (S.D.) FMD value in diabetic subjects (8.9 ± 5%) was lower (P< 0.0001) when compared with the group of control subjects (18.8 ± 7.5%). However, there was no difference in the age-adjusted FMD values between diabetic subjects with and without complications (7.3 ± 3.3% versus 10.5 ± 5.9%). FMD levels did not vary significantly between sexes in both non-diabetic and diabetic groups. FMD correlated negatively with carotid IMT (r =-0.23, P< 0.05). In multiple linear regression analysis, age adjusted FMD was associated only with type 2 diabetes with complications (P = 0.012). The variance explained was 21.9%. Conclusion: Abnormal FMD and increased carotid IMT were present in type 2 diabetes. Both these parameters negatively correlated with each other supporting an association between impaired FMD and atherogenesis. As these abnormalities existed even in diabetic subjects with no microvascular complications, it is likely that they preceded the development of these complications. © 2003 Elsevier Ireland Ltd. All rights reserved. Keywords: Type 2 diabetes; Diabetic nephropathy; Diabetic retinopathy; Flow mediated dilatation; Carotid intimal media thickness 1. Introduction Type 2 diabetes mellitus is characterized by early development of atherosclerosis resulting in high ∗ Corresponding author. Tel.: +91-44-2595-49-13-15; fax: +91-44-2595-49-19. E-mail address: dr vijay@vsnl.com (V. Viswanathan). mortality and morbidity [1]. Impairment of vascular endothelial function is the initial step in the develop- ment of atherosclerosis [2]. Endothelial dysfunction is an important determinant of altered vascular re- activity and plays a major role in the genesis of micro- and macro-vascular complications in diabetes [3–5]. Endothelial dysfunction is also found in con- ditions such as hypertension [6], dyslipidaemia [7,8], 0168-8227/$ – see front matter © 2003 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.diabres.2003.11.015