title: Autonomic changes in psychogenic nonepileptic seizures: toward a potential diagnostic biomarker?
abstract: Disturbances of the autonomic nervous system (ANS) are common in neuropsychiatric disorders. Disease specific alterations of both sympathetic and parasympathetic activity can be assessed by heart rate variability (HRV), whereas electrodermal activity (EDA) can assess sympathetic activity. In posttraumatic stress disorder (PTSD), parasympathetic HRV parameters are typically decreased and EDA is increased, whereas in major depressive disorder (MDD) and dissociation, both parasympathetic and sympathetic markers are decreased. ANS abnormalities have also been identified in psychogenic nonepileptic seizures (PNES) by using HRV, indicating lower parasympathetic activity at baseline. In addition to reviewing the current literature on ANS abnormalities in PTSD, MDD, and disorders with prominent dissociation, including borderline personality disorder (BPD), this article also presents data from a pilot study on EDA in patients with PNES. Eleven patients with PNES, during an admission to our epilepsy monitoring unit (EMU), were compared with 9 with generalized tonic-clonic seizures (GTCS). The area under the EDA curve, the number of EDA responses lasting longer than 2 seconds, and the number of EDA surges during sleep (sympathetic sleep storms) were calculated on ictal and interictal days by an automated algorithm. EDA changes in PNES patients did not follow a systematic pattern of sympathetic hyperarousal (like EDA after GTCS) but were more variable. How specific PNES semiologies, and/or underlying neuropsychiatric disorders, may influence ictal and interictal EDA patterns, and lead to a novel diagnostic biomarker remains to be evaluated in future larger studies.
authors.affiliation: Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Institute of Sports Medicine, University of Paderborn, Paderborn, Germany reinsberger@sportmed.upb.de.
authors.forename: Claus
authors.initials: C
authors.lastname: Reinsberger
authors.affiliation: Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Rani
authors.initials: R
authors.lastname: Sarkis
authors.affiliation: Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Christos
authors.initials: C
authors.lastname: Papadelis
authors.affiliation: Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Chiran
authors.initials: C
authors.lastname: Doshi
authors.affiliation: Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Perez
authors.affiliation: Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Gaston
authors.initials: G
authors.lastname: Baslet
authors.affiliation: Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Tobias
authors.initials: T
authors.lastname: Loddenkemper
authors.affiliation: Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Dworetzky
mesh_terms: D000328:Adult; D000368:Aged; D001143:Arousal / Q000502:physiology; D001341:Autonomic Nervous System / Q000503:physiopathology*; D015415:Biomarkers; D003291:Conversion Disorder / Q000175:diagnosis* / Q000503:physiopathology*; D003937:Diagnosis, Differential; D004827:Epilepsy / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011602:Psychophysiologic Disorders / Q000175:diagnosis* / Q000503:physiopathology*
chemical_list: D015415:Biomarkers
keywords: autonomic nervous system (ANS); electrodermal activity (EDA); heart rate variability (HRV); psychogenic nonepileptic seizures (PNES)