title: Respiratory sinus arrhythmia is reduced in adolescent major depressive disorder.
abstract: OBJECTIVE
  Although the emotion regulatory difficulties in patients with major depressive disorder (MDD) are predicted to associate with impaired cardiovascular autonomic regulation, the changes of cardiac vagal regulation MDD are incompletely understood. The aim of the study was to evaluate the respiratory sinus arrhythmia (as an index of cardiac vagal regulation) using the spectral analysis in high frequency band of the heart rate variability and the indices of deep breathing test in adolescent patients with major depressive disorder.
  
  
  METHODS
  Twenty-eight adolescent girls were examined - 14 patients with major depressive disorder without pharmacological treatment (average age: 16.4 +/- 0.2 yr) and 14 healthy probands (control group) matched for age and gender. The respiratory sinus arrhythmia was evaluated using the spectral analysis in high frequency band of the heart rate variability (HF-HRV) and the parameters of deep breathing test (I-E, I/E). In addition, mean R-R interval was calculated.
  
  
  RESULTS
  The adolescent patients with MDD has significantly reduced spectral activity in the HF-HRV and lower I/E, I-E parameters compared to marched health subjects (P<0.05).
  
  
  CONCLUSIONS
  We conclude that the adolescents girls with MDD have reduced respiratory sinus arrhythmia indicating cardiac vagal dysregulation. Since impaired cardiac vagal regulation is associated with increased risk of cardiovascular morbidity, this finding underscores the importance of impaired autonomic neuro-cardiac integrity already in adolescents with major depressive disorder without pharmacological treatment.
authors.affiliation: Institute of Physiology, Jessenius Faculty of Medicine, Comenius University, Martin Faculty Hospital, Martin, Slovakia. tonhajzerova@jfmed.uniba.sk
authors.forename: I
authors.initials: I
authors.lastname: Tonhajzerova
authors.forename: I
authors.initials: I
authors.lastname: Ondrejka
authors.forename: M
authors.initials: M
authors.lastname: Javorka
authors.forename: P
authors.initials: P
authors.lastname: Adamik
authors.forename: Z
authors.initials: Z
authors.lastname: Turianikova
authors.forename: V
authors.initials: V
authors.lastname: Kerna
authors.forename: K
authors.initials: K
authors.lastname: Javorka
authors.forename: A
authors.initials: A
authors.lastname: Calkovska
mesh_terms: D000293:Adolescent; D001146:Arrhythmia, Sinus / Q000209:etiology*; D003865:Major Depressive Disorder / Q000503:physiopathology*; D005260:Female; D006321:Heart / Q000294:innervation*; D006339:Heart Rate; D006801:Humans; D014630:Vagus Nerve / Q000503:physiopathology