CARDIAC AUTONOMIC NEUROPATHY AND BLOOD-PR ESSURE VARIABILITY IN INSULIN-DEPENDENT DIABETES-MELLITUS

The aim of this study was to analyse the role of cardiac autonomic neu ropathy (CAN) in the changes of Blood-Pressure (BP) variabilitiy among insulin-dependent diabetics and to determine the relationship between BP variability and diabetic complications. Ambulatory BP monitoring w as performed during 24 hours on 93 insulin-dependent diabetics and 77 normal subjects of similar age (Group 1). CAN was assessed by the card iovascular autonomic function tests described by Ewing and the diabeti cs were divided in two groups : Group 2 including patients without CAN (n = 46) and Group 3 including patients with CAN (n = 47). The 24 h s tandard deviation (variability) and the day/night difference for systo lic and diastolic BP were calculated for each subjects. Systolic and d iastolic BP variability is more elevated in Group 3 than in the other groups during the diurnal period. Furthermore, the day/night differenc e of systolic and diastolic BP is lower in Group 3 compared to groups 2 and 3. Diabetic complications are also more frequently observed amon g diabetic patients with CAN (p < 0,00 1). So CAN seems to have two ty pes of consequences on BP curve among diabetic patients: a decrease of day/night BP difference which can be responible of relative hypertens ion during the night and an increase of BP variability. As frequency o f diabetic retinopathy and nephropathy is more elevated among diabetic patients with CAN, it is possible that CAN plays a role in the occurr ence of these complications. Therefore, a simple juxtaposition of thes e facts is also possible.