Flow mediated dilatation and carotid intimal media thickness in South Indian type 2 diabetic subjects

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.