title: The deceleration capacity - a new measure of heart rate variability evaluated in patients with schizophrenia and antipsychotic treatment.
abstract: BACKGROUND
  Schizophrenia is associated with increased cardiac mortality. A disturbed autonomic modulation of heart rate (HR) has been described in patients with schizophrenia in whom antipsychotic medication may represent an additional cardiac risk. The novel measure deceleration capacity (DC) of heart rate predicts cardiac mortality in patients with cardiovascular illnesses. The aim of the present paper was to calculate DC in patients with schizophrenia and to compare this measure with established parameters of heart rate variability (HRV).
  
  
  METHODS
  HRV and DC were calculated in 24-hour electrocardiogram (ECG) recordings of 20 unmedicated, 40 medicated patients with schizophrenia and 40 controls. As activity has a major influence on HRV, 4-hour periods of "sleep-" and "wake-" ECG were evaluated as additional parameters. Actigraphy was used to ensure comparable levels of activity in patients and controls.
  
  
  RESULTS
  The DC as well as the other established HRV measures were not significantly different comparing unmedicated patients with schizophrenia to healthy controls. However, medicated patients showed a significant reduction of DC calculated from ECG recordings during 4 hour over night periods.
  
  
  CONCLUSIONS
  Calculation of DC might contribute to a better monitoring and identification of an increased risk of cardiac mortality in patients with schizophrenia undergoing antipsychotic treatment.
authors.affiliation: Technische Universität München, Klinik für Psychiatrie und Psychotherapie, Ismaninger Str 22, 81675 München, Germany. andreas.birkhofer@lrz.tum.de
authors.forename: A
authors.initials: A
authors.lastname: Birkhofer
authors.forename: J
authors.initials: J
authors.lastname: Geissendoerfer
authors.forename: P
authors.initials: P
authors.lastname: Alger
authors.forename: A
authors.initials: A
authors.lastname: Mueller
authors.forename: M
authors.initials: M
authors.lastname: Rentrop
authors.forename: T
authors.initials: T
authors.lastname: Strubel
authors.forename: S
authors.initials: S
authors.lastname: Leucht
authors.forename: H
authors.initials: H
authors.lastname: Förstl
authors.forename: K-J
authors.initials: KJ
authors.lastname: Bär
authors.forename: G
authors.initials: G
authors.lastname: Schmidt
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001341:Autonomic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D003654:Deceleration; D005260:Female; D006321:Heart / Q000187:drug effects / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*
chemical_list: D014150:Antipsychotic Agents