title: Depressive symptoms and heart rate variability in postmenopausal women.
abstract: BACKGROUND
  Depressive symptoms have been associated with increased cardiac morbidity and mortality rates, but the pathophysiologic mechanism linking depressive symptoms to cardiovascular outcome has yet to be fully understood. Lower heart rate variability has also been associated with increased risk of cardiac events in healthy individuals and in patients with coronary artery disease. Findings regarding a relationship between depressive symptoms and heart rate variability that could explain increased cardiovascular risk have been inconsistent across studies.
  
  
  METHODS
  As an ancillary study to the Women's Health Initiative Observational Study, 3372 postmenopausal women aged 50 to 83 years were enrolled for further evaluation using 24-hour ambulatory electrocardiographic monitoring. A shortened version of the Center for Epidemiological Studies Depression Scale and the Diagnostic Interview Schedule were administered. Women with adequate electrocardiographic data and depressive symptom information and without coronary artery disease were analyzed (n = 2627).
  
  
  RESULTS
  Two hundred sixty-nine women (10.2%) had depressive symptoms as measured using the 2 instruments. Women with depressive symptoms had a higher mean +/- SD heart rate (77.4 +/- 9.6 vs 75.5 +/- 8.5 beats/min) and lower heart rate variability than women without depressive symptoms. All differences remained significant after adjusting for age (P<.01).
  
  
  CONCLUSIONS
  Women with depressive symptoms had significant reductions in heart rate variability and higher heart rates, suggestive of increased sympathetic tone. These findings may contribute to the increased cardiac morbidity and mortality rates associated with depression in other studies.
authors.affiliation: Division of Cardiovascular Medicine, University of Florida, Gainesville 32610-0277, USA.
authors.forename: Chin K
authors.initials: CK
authors.lastname: Kim
authors.forename: Susan P
authors.initials: SP
authors.lastname: McGorray
authors.forename: Beth A
authors.initials: BA
authors.lastname: Bartholomew
authors.forename: Michelle
authors.initials: M
authors.lastname: Marsh
authors.forename: Tammy
authors.initials: T
authors.lastname: Dicken
authors.forename: Sylvia
authors.initials: S
authors.lastname: Wassertheil-Smoller
authors.forename: J David
authors.initials: JD
authors.lastname: Curb
authors.forename: Albert
authors.initials: A
authors.lastname: Oberman
authors.forename: Judith
authors.initials: J
authors.lastname: Hsia
authors.forename: Julius
authors.initials: J
authors.lastname: Gardin
authors.forename: Nathan D
authors.initials: ND
authors.lastname: Wong
authors.forename: Bruce
authors.initials: B
authors.lastname: Barton
authors.forename: Robert P
authors.initials: RP
authors.lastname: McMahon
authors.forename: David S
authors.initials: DS
authors.lastname: Sheps
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000150:complications* / Q000503:physiopathology; D002318:Cardiovascular Diseases / Q000150:complications; D003866:Depressive Disorder / Q000150:complications*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause; D012737:Sex Factors