Radial augmentation index and diabetic complications in patients with type 2 diabetes mellitus

Background: Increased arterial stiffness is associated with cardiovascular diseases. Aortic augmentation index (AI) depends on arterial stiffness, although its relation with diabetic complications was not fully understood. Using radial AI as a surrogate index for aortic AI, we studied the relationship between radial AI and diabetic micro- and macroangiopathy in patients with type 2 diabetes mellitus. Methods: Radial and carotid AIs were measured using pulse wave analysis by tonometry in 210 male diabetic patients and re-examined in 95 patients with constant medications after a 6-month interval. Results: Radial AI correlated significantly with simultaneously measured carotid AI (r = 0. 44, p < 0. 001). Radial AI was positively correlated with age, systolic blood pressure and pulse wave velocity, and negatively correlated with height and ankle brachial pressure index (ABI). Multiple regression analysis showed that height, systolic blood pressure and ABI were independently related to radial AI. At the follow-up measurement, the changes in radial AI were independently associated with those in systolic blood pressure and ABI. Radial AI was significantly increased in diabetic patients with clinically evident macroangiopathy, but not those with retinopathy, neuropathy or nephropathy compared with those without. Radial AI was significantly increased in patients with ABI <0. 9 and toe-brachial pressure index (TBI) <0. 6, but not in those with ABI ≥0. 9 and TBI <0. 6 compared with those with ABI ≥0. 9 and TBI ≥0. 6. Conclusions: Radial AI may be used as a surrogate measurement of aortic AI in diabetic patients, and was increased in those with clinically evident macroangiopathy but not with microangiopathy. © 2011 The Japan Diabetes Society.