Association of cardiac autonomic neuropathy with arterial stiffness in type 2 diabetes mellitus patients

Background: Diabetic patients are at the risk of cardiac autonomic neuropathy (CAN) and arterial stiffness. This study aimed to investigate the association of heart rate variability (HRV) as an index for CAN and pulse wave velocity (PWV) as an index for arterial stiffness. Methods: Uncomplicated diabetes type-2 patients who had no apparent history of cardiovascular condition underwent HRV and PWV measurements and the results were compared with the control group consisting of non-diabetic peers. Also, the findings were adjusted for the cardiovascular risk factors and other confounding factors. Results: A total of 64 diabetic patients (age= 52.08 +/- 8.50 years; males=33 [51.6%]) were compared with 57 controls (age= 48.74 +/- 6.18 years; males=25 [43.9%]) in this study. Hypertension, dyslipidemia, and thereby systolic blood pressure and statin use were significantly more frequent in the diabetic group, while the serum levels of cholesterol, HDL-C and LDL-C were significantly higher in the controls. Pulse wave was significantly increased in the diabetic patients (p<0.001). Main HRV parameters were significantly lower in diabetics than in controls. After adjustment for the confounders, PWV and HRV remained significantly different between the groups (p=0.01 and p=0.004, respectively). Multiple logistic regression of the association between pulse wave velocity and HRV index was independently significant both in diabetics and controls. Conclusions: There exists a significant relationship between heart rate variability and arterial stiffness as a measure for atherosclerosis in diabetic patients, although the role of the confounding factors is noteworthy.