title: High-resolution joint symbolic analysis to enhance classification of the cardiorespiratory system in patients with schizophrenia and their relatives.
abstract: Schizophrenia as a mental illness is one of the most serious in the world. Patients with schizophrenia have an increased cardiac mortality rate, but the reasons for this remain unclear. In addition to other factors, the role of impaired autonomic regulation during acute psychosis has become more evident in different studies applying heart rate (HR) variability analyses. But, until now, respiration and cardiorespiratory regulation, which are important for homeostatic control, have not been considered. In this study, short-term cardiorespiratory couplings (CRCs) of 23 unmedicated patients with paranoid schizophrenia (SZO), 20 of their healthy first-degree relatives (REL) and 20 healthy subjects (CON) matched according to age and sex of SZO and REL were investigated by applying high-resolution joint symbolic dynamics (HRJSD) analysis. We found a significantly (p<0.0061) altered HR pattern, respiratory pattern and CRCs in SZO and only marginal alterations for the REL group in comparison with the CON group when we applied HRJSD. These results might be an indication of decreased vagal activity within the brainstem, an altered or suppressed interaction of the brainstem and higher regulatory centres, or panic- and anxiety-related changes in the brainstem associated with the acute psychosis of these patients.
authors.affiliation: Department of Medical Engineering and Biotechnology, Ernst-Abbe-Hochschule Jena, University of Applied Sciences, Jena, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Schulz
authors.affiliation: Institute of Biomedical Engineering and Informatics, Ilmenau University of Technology, Ilmenau, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Haueisen
authors.affiliation: Department of Psychiatry and Psychotherapy, University Hospital, Jena, Germany.
authors.forename: Karl-Jürgen
authors.initials: KJ
authors.lastname: Bär
authors.affiliation: Department of Medical Engineering and Biotechnology, Ernst-Abbe-Hochschule Jena, University of Applied Sciences, Jena, Germany voss@fh-jena.de.
authors.forename: Voss
authors.initials: V
authors.lastname: Andreas
mesh_terms: D000328:Adult; D000465:Algorithms; D001341:Autonomic Nervous System / Q000503:physiopathology; D002319:Cardiovascular System; D016022:Case-Control Studies; D004562:Electrocardiography; D005192:Family Health; D005260:Female; D006321:Heart / Q000503:physiopathology; D006339:Heart Rate; D006801:Humans; D008297:Male; D015233:Models, Statistical; D012119:Respiration; D056152:Respiratory Rate; D012563:Schizophrenia, Paranoid / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted; D014630:Vagus Nerve; D055815:Young Adult
keywords: autonomic nervous system; cardiorespiratory coupling; heart rate variability; joint symbolic dynamics; respiration; schizophrenia