Association between cardiac autonomic neuropathy and peripheral neuropathy in diabetes mellitus type 1

Abstract

Introduction: Cardiovascular autonomic neuropathy (CAN) is defined as the impairment of autonomic control of the cardiovascular system. The prevalence of CAN varies widely from 2.5 to 50%. Neural damage by chronic hyperglycaemia, vascular insufficiency in the vessels supplying the nerves, and autoimmune mechanisms have been suggested as possible causes of CAN, its pathogenesis remains poorly understood. As in the case of diabetic peripheral neuropathies (DPN), disease duration and longterm poor glycaemic control are important risk factors for the development of CAN. Purpose and Objectives: Evaluation of the con-elation between CAN and peripheral neuropathy in type 1 diabetes (T1DM). Materials and Methods: In study were included 27 patients (10 men and 17 women) with T1DM and CAN (the diagnosis of CAN was established on the basis of changes in heart rate and blood pressure, during cardiovascular reflex tests, Ewing's battery). According to the total score of the CAN severity, patients were divided in 3 groups. Were evaluated: T1DM duration and severity of peripheral neuropathy. Results: The l sl group included 11 patients (40.7%) with mild CAN, which were discovered DPN mild - 6 patients (22.2%), DPN moderate - 5 patients (18.5%). T1DM average duration was 5.5±2.0 years. After analysis by the statistical method MedCalc 12.7.2 we detect significant correlation with mild DPN (r=0.645, p=0.0003). The 2nd group was made by 8 patients (29.6%) with moderate CAN, which were observed the presence of DPN moderate - 6 patients (22.2%) and DPN severe - 2 patients (7.4%). In this group the T1DM average duration was 13.6±5.5 years. Important correlation with moderate DPN (r=0.452, p=0.017). In the 3rd group were aded 8 patients (29.6%) with severe CAN, which had severe DPN. The average duration of T1DM was 18.9±7.6 years. In this group were observed more significant correlation with duration of T1DM (r=0.585, p=0.0013) and severe DPN (r=0.846, p<0.001). Conclusions: 1. Cardiac autonomic neuropathy severity correlates with peripheral neuropathy severity in type 1 diabetes. 2. Cardiac autonomic neuropathy and peripheral neuropathy severity increases with the duration of type 1 diabetes.