title: Cardio-respiratory coupling indicates suppression of vagal activity in acute schizophrenia.
abstract: Altered amygdala activity in patients with schizophrenia can influence respiratory patterns and consequently cardiovascular parameters. Hence, we examined respiration and heart rate time series complexity as well as coupling of both signals. Electrocardiograms and respiratory signals were obtained from 25 unmedicated patients with schizophrenia and controls. Approximate entropy (ApEn) was calculated for heart and respiratory rates as well as cross-ApEn reflecting coupling of both signals. Coupling was decreased indicating diminished vagal modulation at the brain stem level. Regularity of breathing correlated with disease severity. These data might reflect a lack of inhibitory control over brainstem centers in schizophrenia.
authors.affiliation: Department of Psychiatry and Psychotherapy, University Hospital, Philosophenweg 3, Jena, Germany.
authors.forename: Jeannine
authors.initials: J
authors.lastname: Peupelmann
authors.forename: Michael Karl
authors.initials: MK
authors.lastname: Boettger
authors.forename: Carmen
authors.initials: C
authors.lastname: Ruhland
authors.forename: Sandy
authors.initials: S
authors.lastname: Berger
authors.forename: Chaitra T
authors.initials: CT
authors.lastname: Ramachandraiah
authors.forename: Vikram K
authors.initials: VK
authors.lastname: Yeragani
authors.forename: Karl-Jürgen
authors.initials: KJ
authors.lastname: Bär
mesh_terms: D000328:Adult; D004562:Electrocardiography / Q000379:methods; D019277:Entropy; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017711:Nonlinear Dynamics; D015656:Respiratory Mechanics / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology*; D018709:Statistics, Nonparametric; D013997:Time Factors; D055815:Young Adult