Aortic distensibility is reduced in subjects with type 2 diabetes and cardiac autonomic neuropathy

Reduced aortic distensibility predicts cardiovascular mortality in patients with type 2 diabetes and impaired glucose tolerance. Cardiac autonomic neuropathy is common in subjects with diabetes. However, the relationship between the elastic properties of the aorta and autonomic neuropathy has not been studied to date in subjects with type 2 diabetes.

In this cross-sectional study, a total of 87 subjects with type 2 diabetes (27 with and 60 without cardiac autonomic neuropathy) as well as 60 healthy individuals, matched for age and sex with the diabetic subjects, were examined. Cardiac autonomic neuropathy was diagnosed on the basis of the battery of the classic cardiovascular autonomic function tests. Aortic distensibility was assessed by high-resolution ultrasonography.

Diabetic patients had reduced aortic distensibility in comparison with the control subjects: 1.81 +/- 0.58 vs. 2.53 +/- 0.34 10-6 cm2 dyn-1, respectively (P < 0.0001). In addition, diabetic individuals with cardiac autonomic neuropathy had reduced aortic distensibility as compared with patients without this complication: 1.60 +/- 0.72 vs. 1.90 +/- 0.48 10-6 cm2 dyn-1, respectively (P = 0.02). Multivariate linear regression analysis in the diabetic group, after controlling for a number of confounding factors such as age, systolic and diastolic blood pressure, duration of diabetes and presence as well as severity of cardiac autonomic neuropathy, demonstrated a significant and independent association between duration of diabetes [B = -0.02, SE(B) = 0.01, P = 0.01] and presence of cardiac autonomic neuropathy [B = -0.29, SE(B) = 0.14, P = 0.03] with aortic distensibility.

Type 2 diabetes is associated with a significant reduction in the elastic properties of the aorta. In addition, known duration of diabetes and presence of cardiac autonomic neuropathy are the main predictors of aortic distensibility in subjects with type 2 diabetes.