Improvement of cardiovascular autonomic function after 2 years of good glycaemic control in diabetes type 1

Abstract

INTRODUCTION. The autonomic cardiovascular neuropathy in diabetes is associated with an increased risk of sudden death. The aim of the study was the prospective analysis of the difference in autonomic function tests during 2 year follow-up regard to the level of metabolic compensation.
MATERIAL AND METHODS. Ninety eight patients with diabetes type 1 were examined at baseline, after 12 and 24 months for autonomic dysfunction, by using the computer device ProSciCard. Parameters of the following tests were analysed: heart rate variability at 5 min rest (time and frequency domain analysis), deep breathing, lying-to-standing heart rate changes, Valsalva manoeuvre, lying-to-standing blood pressure changes, sustained handgrip. Patients were divided into 3 groups: well, intermediate and poorly compensated. The divisions were made using the mean HbA_1c, taken every 6 months during the study.
RESULTS. The significant differences for the following parameters between groups were found: at the initial visit - no differences; after 12 months for SDRR_R, CV_R, RMSSD_R, HF_R, SDRR_DB, RMSSD_DB, E_INDEX, PioΔDSCTK1; after 24 months for HR_R, SDRR_R, RMSSD_R, PioΔDSCTK1. After 12 and 24 months the best values were found in well controlled subjects and the worst values were in poorly controlled ones.
CONCLUSIONS: Metabolic compensation of diabetes is a very important factor determining the course of cardiovascular neuropathy. Good metabolic control of the disease can improve autonomic function tests, whereas poor control leads to an inevitable deterioration of the autonomic nervous system.