title: [Relationships between baroreflex gain and pulsatile stress in type 1 diabetic patients].
abstract: OBJECTIVE
  Cardiovascular autonomic neuropathy (CAN) and early arterial stiffness are frequent complications in type 1 diabetes. The aim of our work is to study the relationships between CAN (estimated by baroreflex gain calculation) and arterial stiffness (estimated by pulsatile stress) in type 1 diabetic patients.
  
  
  METHODS
  In a cross-sectional study, we calculated baroreflex gain and pulsatile stress in 167 type 1 diabetic patients and 160 matched non-diabetic subjects whose blood pressure was continuously monitored with a Finapres(®) device in a postural test (squatting test). The baroreflex gain was calculated by plotting the pulse intervals (R-R) against systolic blood pressure values during the transition phase from squatting to standing. Pulsatile stress was estimated by the pulse pressure×heart rate product. In a longitudinal study, the baroreflex gain and pulsatile stress were calculated before and after a mean follow-up of 79±33 months in type 1 diabetic patients.
  
  
  RESULTS
  Cross-sectional data showed a decrease in baroreflex gain and an increase in pulsatile stress in type 1 diabetic patients versus the matched non-diabetic subjects. A significant correlation between the baroreflex gain and pulsatile stress was present. Type 1 diabetic patients with lower baroreflex gain had a higher value of pulsatile stress when compared to those with higher baroreflex gain. During follow-up, a significant reduction in baroreflex gain (but without significantly increased pulsatile stress) was observed. A univariate analysis showed that the decrease of the baroreflex gain is not correlated with the time interval between the two tests, neither type 1 diabetes duration nor mean glycated hemoglobin values, but significantly with the pulsatile stress increase.
  
  
  CONCLUSIONS
  In type 1 diabetic patients, the baroreflex gain is decreased and the pulsatile stress is increased when these markers are compared to age-matched non-diabetic subjects. There is a relationship between indices of CAN and arterial stiffness. Nevertheless, the baroreflex gain (marker of CAN) is impaired earlier than the pulsatile stress in this type 1 diabetic population with inadequate glycaemic control.
authors.affiliation: Service de diabétologie, nutrition et maladies métaboliques, CHU Sart-Tilman, université de Liège, Liège, Belgique. andre.scheen@chu.ulg.ac.be
authors.forename: A J
authors.initials: AJ
authors.lastname: Scheen
authors.forename: M
authors.initials: M
authors.lastname: Marchand
authors.forename: J-C
authors.initials: JC
authors.lastname: Philips
mesh_terms: D000328:Adult; D000465:Algorithms; D000704:Analysis of Variance; D017704:Baroreflex; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged