title: Autonomic modulation in healthy first-degree relatives of patients with major depressive disorder.
abstract: BACKGROUND
  Cardiac mortality is known to be increased in patients with major depression. Several studies have reported an imbalance within the autonomic nervous system (ANS) of patients with major depressive disorder (MDD) as one putative cause. Since a heritability of autonomic modulation was demonstrated in healthy subjects, we aimed to investigate autonomic modulation in first-degree relatives of patients with MDD to find potential autonomic imbalances.
  
  
  METHODS
  We included 30 patients with MDD, 30 of their first-degree relatives (siblings or offspring) and 30 matched healthy controls in our study. We obtained a high resolution electrocardiogram and beat to beat blood pressure measurements for 30 min at rest. Linear and nonlinear parameters of heart rate variability (HRV) and baroreflex sensitivity (BRS) were calculated.
  
  
  RESULTS
  Parameters of HRV and BRS did not differ significantly between relatives and controls. We found significant differences between patients and controls for some HRV and BRS parameters confirming results of previous studies.
  
  
  CONCLUSIONS
  Findings of our study suggest that an imbalance of autonomic function is related to patients with depression and not to first-degree relatives. Thus, a genetic background for autonomic dysfunction is rather unlikely.
authors.affiliation: Pain & Autonomics-Integrative Research, Department of Psychiatry and Psychotherapy, University Hospital, Philosophenweg 3, 07743 Jena, Germany.
authors.forename: Sandy
authors.initials: S
authors.lastname: Berger
authors.forename: Steffen
authors.initials: S
authors.lastname: Schulz
authors.forename: Christine
authors.initials: C
authors.lastname: Kletta
authors.forename: Andreas
authors.initials: A
authors.lastname: Voss
authors.forename: Karl-Jürgen
authors.initials: KJ
authors.lastname: Bär
mesh_terms: D000328:Adult; D001341:Autonomic Nervous System / Q000473:pathology* / Q000503:physiopathology*; D001342:Autonomic Nervous System Diseases / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology; D017704:Baroreflex / Q000502:physiology; D001795:Blood Pressure Determination; D003865:Major Depressive Disorder / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology*; D004562:Electrocardiography; D005190:Family; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010551:Personality; D055815:Young Adult