title: Effects of normal blood pressure, prehypertension, and hypertension on autonomic nervous system function.
abstract: BACKGROUND
  Autonomic nervous system plays an important role in blood pressure (BP) regulation, and large proportion of patients with hypertension have increased sympathetic and decreased parasympathetic activity. Heart rate recovery (HRR) is a simple non-invasive measurement for investigating autonomic nervous system influence on the cardiovascular system; however, this methodology has not been used to evaluate autonomic nervous system in subjects with prehypertension (PHT). Accordingly, the present study was designed to evaluate HRR in subjects with PHT.
  
  
  RESULTS
  We measured HRR of 91 subjects with PHT, 44 patients with hypertension, and 53 normotensive healthy volunteers. HRR was significantly lower in the HT and PHT groups as compared to the control group (24.4 ± 5.7, 26.0 ± 8.4, 30.0 ± 8.7; hypertension, PHT, and control groups, respectively), but it did not significantly differ between HT and PHT groups. HRR was significantly and inversely correlated with age, systolic and diastolic BP, fasting and postprandial glucose level, waist circumference, total cholesterol, LDL cholesterol and non-HDL cholesterol, whereas exercise duration and METs were positively correlated with HRR. In multivariable analysis, we found that systolic BP, postprandial glucose level and exercise duration were independent predictors of lower HRR.
  
  
  CONCLUSIONS
  HRR, a non-invasive measurement analyzing the dysfunction in autonomic nervous system, was reduced in subjects with PHT as compared to normotensives, and the subjects with PHT had HRR as lower as patients with HT did. Our findings are supportive for the hypothesis that autonomic dysregulation is present in an early stage of essential hypertension.
authors.affiliation: Suleyman Demirel University, Faculty of Medicine, Cardiology Department, Isparta, Turkey. aydoganer@yahoo.com
authors.forename: Dogan
authors.initials: D
authors.lastname: Erdogan
authors.forename: Emel
authors.initials: E
authors.lastname: Gonul
authors.forename: Atilla
authors.initials: A
authors.lastname: Icli
authors.forename: Habil
authors.initials: H
authors.lastname: Yucel
authors.forename: Akif
authors.initials: A
authors.lastname: Arslan
authors.forename: Salaheddin
authors.initials: S
authors.lastname: Akcay
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ozaydin
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000502:physiology*; D001342:Autonomic Nervous System Diseases / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D058246:Prehypertension / Q000503:physiopathology*; D013312:Stress, Physiological / Q000502:physiology