CORRELATION BETWEEN FASTING PLASMA GLUCOSE AND AUTONOMIC DYSFUNCTION IN HEALTHY SUBJECTS WITH NORMOGLYCEMIA: AN EARLY IMPAIRMENT IN CARDIOVASCULAR ADAPTATION: PP.17.144

Abstract

Objective: Autonomic neuropathy associated with the higher risk of cardiovascular mortality. It is known, that the autonomic dysfunction appears in the early phases of the disturbances of the carbohydrate metabolism already. The aim of this study was to determine the correlations between autonomic dysfunction and the fasting plasma glucose in healthy subjects with a normal carbohydrate metabolism according to the WHO criteria, normal body weight and blood pressure. Design and Method: 14 healthy subjects were included. Autonomic function was investigated by means of the five standard cardiovascular reflex tests, heart rate variability (HRV) and the spontaneous baroreflex sensitivity (BRS). The blood pressure was measured continuously with the Finapres 2300. The ECG signal was detected continuously by means of a Siemens Sirecust 730 ECG. The signals were fed through an analog-digital converter into a computer and analysed off-line. The oscillation amplitude of R-R intervals were analysed as well as the time and frequency domain indexes of HRV. The spontaneous BRS was calculated in the supine position and after standing up and based on the analysis of the spontaneous fluctuations of blood pressure and interbeat intervals. Statistical analysis was performed by SPSS program. Results: There were statistical significant negative relationships between the fasting plasma glucose and the heart rate response to deep breathing (r = -0.58, p < 0.05), the heart rate response to standing up (r = -0.56, p < 0.05), standard deviation of all RR intervals (r = -0.59, p < 0.05), root mean square of successive RR differences (r = -0.57, p < 0.05), power of low frequency component of HRV (r = -0.56, p < 0.05), power of high frequency component of HRV (r = -0.57, p < 0.05) and the BRS after standing up (r = -0.56, p < 0.05). There were no statistical differences between the fasting plasma glucose and the another cardiovascular reflex tests. Conclusions: Our results suggest the existence of a close relationship between the increase of the normal range for fasting plasma glucose in healthy subjects and the autonomic dysfunction which may forecast the early cardiovascular adaptation damage.