title: Autonomic and cardiovascular function in postmenopausal women: the effects of estrogen versus combination therapy.
abstract: OBJECTIVE
  This study examined the effects of oral estrogen (ERT) alone versus oral estrogen/medroxyprogesterone acetate (HRT) therapy on cardiovascular function, as controlled by the autonomic nervous system.
  
  
  METHODS
  Forty-three postmenopausal women received ERT, HRT, or a placebo for 3 months in a double-blind, randomized, placebo-controlled study. Cardiovascular hemodynamics and heart rate variability were assessed at rest and during stress.
  
  
  RESULTS
  After 3 months of therapy, oral HRT significantly increased high-frequency power (P =.0002) and decreased total peripheral resistance (P =.04). The changes were evident at rest and during stress.
  
  
  CONCLUSIONS
  Our findings suggest that combination therapy produces a more favorable alteration of autonomic cardiovascular function than estrogen alone (ie, combination therapy increases vagal activity).
authors.affiliation: Department of Psychiatry, University of California, San Diego, UCSD Medical Center, 92103-0804, USA. nfarag@ucsd.edu
authors.forename: Noha H
authors.initials: NH
authors.lastname: Farag
authors.forename: Richard A
authors.initials: RA
authors.lastname: Nelesen
authors.forename: Barbara L
authors.initials: BL
authors.lastname: Parry
authors.forename: Jose S
authors.initials: JS
authors.lastname: Loredo
authors.forename: Joel E
authors.initials: JE
authors.lastname: Dimsdale
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Mills
mesh_terms: D000284:Administration, Oral; D000368:Aged; D001341:Autonomic Nervous System / Q000187:drug effects* / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects; D002320:Cardiovascular Physiological Phenomena / Q000187:drug effects*; D004359:Drug Therapy, Combination; D004958:Estradiol / Q000627:therapeutic use*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D020249:Hormone Replacement Therapy; D006801:Humans; D017258:Medroxyprogesterone Acetate / Q000627:therapeutic use*; D008875:Middle Aged; D017698:Postmenopause / Q000502:physiology*; D045167:Progesterone Congeners / Q000627:therapeutic use*; D014621:Vagina / Q000187:drug effects / Q000502:physiology; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D045167:Progesterone Congeners; D004958:Estradiol; D017258:Medroxyprogesterone Acetate