Increased augmentation index and systolic stress in type 1 diabetes mellitus

Type 1 diabetes mellitus is associated with endothelial dysfunction and inc reased arterial stiffness, both of which may contribute to the excess cardi ovascular mortality in such patients. Arterial stiffening increases pulse w ave velocity and wave reflection, which augments central systolic pressure and stress. Using the non-invasive technique of pulse wave analysis, we inv estigated aortic augmentation and central pressure in 35 patients with type 1 diabetes and 35 matched controls. Peripheral pulse wave-forms were recor ded from the radial artery, central aortic waveforms were then generated, a nd augmentation index (Alx), ascending aortic pressure and tension time ind ex (TTI), a measure of systolic load, were calculated. Peripheral and centr al blood pressure did not differ between the two groups. Air was significan tly elevated in the diabetic patients compared with controls (7.1 +/- 1.6% vs. 0.4 +/- 2.0%; p = 0.01), as was the TTI (2307 +/- 51 mmHg.s.min(-1) vs. 2010 +/- 61 mmHg.s.min (-1); p < 0.001). Estimated pulse wave velocity was also higher in the diabetic group. Type 1 diabetes is associated with an i ncreased Alx and rate of wave travel, indicating enhanced wave reflection a nd increased systemic arterial stiffness, and elevation of the TTI. Such ha emodynamic effects may contribute to the increased left ventricular mass an d risk of cardiovascular disease associated with type 1 diabetes mellitus.