title: Modest weight loss in moderately overweight postmenopausal women improves heart rate variability.
abstract: OBJECTIVE
  To evaluate the effects of weight loss on heart rate (HR) and heart rate variability (HRV) parameters in overweight postmenopausal women.
  
  
  METHODS
  Forty-nine overweight postmenopausal women with an average body mass index of 28.8 ± 1.9 kg/m(2) underwent a 12-week dietary weight-loss programme. Accepted variables for characterization of HRV were analysed before and after the weight loss by 24-h ambulatory ECG monitoring; mean and standard deviation for the time between normal-to-normal complexes (MeanNN and SDNN, respectively), and the mean of standard deviations of normal-to-normal intervals for each 5-min period (SDNNindex). Baseline body fat mass (FM%) and changes in body composition was determined by dual X-ray absorptiometry. Before and after the weight-loss period, total abdominal fat, intra-abdominal fat (IAAT), and subcutaneous abdominal fat (SCAT) were measured by single-slice MRI at L3.
  
  
  RESULTS
  The weight loss of 3.9 ± 2.0 kg was accompanied by an improvement of HRV. SDNN increased by 9.2% (p = 0.003) and SDNNindex increased by 11.4% (p = 0.0003). MeanNN increased by 2.4%, reflecting a decrease in mean heart rate from 74.1 to 72.3 beats/min (p = 0.033). Systolic blood pressure (SBP) decreased by 2.7%, total cholesterol by 5.1% and high-sensitivity C-reactive protein (hsCRP) by 15.8% (p = 0.002). Improvements in SDNN and cholesterol were correlated with weight loss (r = -0.329, p = 0.024 and r = 0.327, p = 0.020, respectively) but changes in HR, SBP, and hsCRP were not. IAAT and the IAAT/SCAT-ratio were found to be negatively associated with HRV parameters but changes in body composition were not associated with changes in HRV.
  
  
  CONCLUSIONS
  The observed improvement of HRV seems to be facilitated by weight loss. IAAT and the IAAT/SCAT ratio were found to be associated with low HRV.
authors.affiliation: Department of Cardiology, Copenhagen University Hospital, Copenhagen, Denmark. mettemouridsen@hotmail.com
authors.forename: Mette Rauhe
authors.initials: MR
authors.lastname: Mouridsen
authors.forename: Nathalie Tommerup
authors.initials: NT
authors.lastname: Bendsen
authors.forename: Arne
authors.initials: A
authors.lastname: Astrup
authors.forename: Steen Bendix
authors.initials: SB
authors.lastname: Haugaard
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Binici
authors.forename: Ahmad
authors.initials: A
authors.lastname: Sajadieh
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D003718:Denmark; D004311:Double-Blind Method; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood; D050152:Intra-Abdominal Fat / Q000503:physiopathology; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D050177:Overweight / Q000097:blood / Q000175:diagnosis / Q000178:diet therapy* / Q000503:physiopathology; D017698:Postmenopause; D050507:Subcutaneous Fat, Abdominal / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D002097:C-Reactive Protein; D002784:Cholesterol