Correlation between arterial wall stiffness, N-terminal prohormone of brain natriuretic peptide, functional and structural myocardial abnormalities in patients with type 2 diabetes mellitus and cardiac autonomic neuropathy

Abstract

Aim: To assess arterial wall stiffness, plasma levels of of N-terminal prohormone of brain natriuretic peptide (NT-proBNP), as well as functional state and structure of the myocardium in patients with type 2 diabetes mellitus (T2DM) and cardiac autonomic neuropathy (CAN). Materials and Methods: The study involved a total of 65 patients with T2DM. 12 had no evidence of cardiovascular disease (CVD) or CAN, 14 were diagnosed with subclinical stage of CAN, 18 - with functional stage, and 21 - with organic stage. We measured aortic pulse wave velocity (PWV), aortic augmentation index (AIx), brachial artery AIx, ambulatory arterial stiffness index (AASI) and plasma levels of NT-proBNP. Clinical examination included ECG, Holter monitoring, ambulatory BP measurement and echocardiography. Results: Patients with isolated T2DM showed a trend for increased vascular wall stiffness. PWV was increased in patients with subclinical stage of CAN. Aortic and brachial AIx, PWV and AASI were elevated in patients with functional stage of CAN, PWV being significantly higher vs. subclinical CAN subgroup. Organic stage was characterized by pathologically increased values of all primary parameters; PWV and AASI were significantly higher compared with other groups. Development and progression of CAN was accompanied by an increase in NT-proBNP plasma levels. Concentration of NT-proBNP was in direct correlation with left ventricular mass (LVM) and PWV. PWV and LVM values also directly correlated between themselves. Conclusion: Development and progression of CAN in patients with T2DM is accompanied by an increase in vascular wall stiffness. The elevation of plasma NT-proBNP in patients with T2DM correlates with the development of CAN and is significantly and independently associated with an increase in LVM and PWV. Our data suggests the pathophysiological interconnection between metabolic, functional and structural myocardial abnormalities in patients with T2DM and CAN.