title: Effect of hormone replacement therapy on heart rate variability in postmenopausal women.
abstract: OBJECTIVE
  To assess the characteristics of autonomic control of heart rate in postmenopausal women before and after hormone replacement therapy (HRT).
  
  
  METHODS
  Time domain and spectral domain heart rate variability (HRV) were performed in 58 postmenopausal women before and after HRT.
  
  
  RESULTS
  Compared with examinations at baseline, values of all HRV measurements in subjects given HRT were increased at the fourth month (P < 0.05), while they remained unchanged in the control group (P > 0.05). Results showed an inverse correlation between all measures of HRV and mean R-R interval in the treatment group.
  
  
  CONCLUSIONS
  HRT reduces sympathetic drive in postmenopausal symptomatic women. HRV may be an index of imbalance of autonomic control in perimenopausal women.
authors.affiliation: Department of Cardiology, People's Hospital, Beijing Medical University, Beijing 100044, China.
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.forename: W
authors.initials: W
authors.lastname: Bai
authors.forename: J
authors.initials: J
authors.lastname: Guo
authors.forename: S
authors.initials: S
authors.lastname: Zheng
authors.forename: J
authors.initials: J
authors.lastname: Zhao
mesh_terms: D001341:Autonomic Nervous System / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D020249:Hormone Replacement Therapy; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause / Q000502:physiology*