title: Nonlinear relationship between electrodermal activity and heart rate variability in patients with acute schizophrenia.
abstract: We investigated to what degree tonic skin conductance levels (SCL) and cardiac autonomic dysfunction are interrelated in schizophrenia. Heart rate variability (HRV) and SCL were simultaneously assessed in 18 unmedicated patients and 18 controls matched for age, sex, weight, and smoking habits. For comparison to prior studies, phasic sympathetic skin responses (SPR) were also recorded. Compared to controls, patients had prolonged SPR latency and reduced SPR amplitude with a right-greater-than-left asymmetry, which was inversely correlated with positive symptoms. An autonomic imbalance was reflected in linear and nonlinear measures of HRV and increased SCL. Patients showed a stronger nonlinear association between SCL and heart rate than controls. HRV and SCL findings were strongly affected by group differences in breathing rate. Stronger HRV-SCL coupling in patients may suggest augmented sympathetic modulation in schizophrenia.
authors.affiliation: Pain & Autonomics-Integrative Research (PAIR), Department of Psychiatry and Psychotherapy, University Hospital Jena, Jena, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Rachow
authors.forename: Sandy
authors.initials: S
authors.lastname: Berger
authors.forename: Michael Karl
authors.initials: MK
authors.lastname: Boettger
authors.forename: Steffen
authors.initials: S
authors.lastname: Schulz
authors.forename: Salvador
authors.initials: S
authors.lastname: Guinjoan
authors.forename: Vikram K
authors.initials: VK
authors.lastname: Yeragani
authors.forename: Andreas
authors.initials: A
authors.lastname: Voss
authors.forename: Karl-Jürgen
authors.initials: KJ
authors.lastname: Bär
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology*; D006321:Heart / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012563:Schizophrenia, Paranoid / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000503:physiopathology*