Flow-Mediated Dilation is Associated with Microalbuminuria Independent of Cardiovascular Risk Factors in Type 2 Diabetes - Interrelations with Arterial Thickness and Stiffness

Aims: To investigate whether endothelial dysfunction assessed by brachial artery flow-mediated dilation (FMD) is associated with urinary albumin excretion (UAE) and is interrelated with carotid intima-media thickness (IMT) and pulse-wave velocity (PWV) in type 2 diabetes. Methods: We measured FMD, IMT and PWV in 158 subjects with type 2 diabetes (normo- 49, micro- 64, macroalbuminuria 45), explored the determinants of FMD, and analyzed the relationship of FMD with traditional cardiovascular risk factors according to IMT and PWV levels. Results: Microalbuminuria was significantly associated with lower FMD, higher IMT and higher PWV compared to normoalbuminuria (p<0.001 for all). FMD was significantly correlated with IMT and PWV, and also with traditional risk factors, UAE, glomerular filtration rate, diabetic retinopathy, and neuropathy. Multivariate regression analysis revealed that UAE remained a significant determinant of FMD independent of traditional risk factors, metabolic control, and renal function. The relationship of FMD with IMT and PWV was less pronounced in subjects with increased IMT and PWV. Conclusions: In individuals with type 2 diabetes, FMD is impaired in subjects with microalbuminuria and is associated with IMT and PWV only when these values are not increased, i.e., at an early stage of atherosclerosis.