title: Which patients with epilepsy are at risk for psychogenic nonepileptic seizures (PNES)? A multicenter case-control study.
abstract: We sought to examine the clinical and electrographic differences between patients with combined epileptic (ES) and psychogenic nonepileptic seizures (PNES) and age- and gender-matched patients with ES-only and PNES-only.
  
  
  
  Data from 138 patients (105 women [77%]), including 46 with PNES/ES (39±12years), 46 with PNES-only (39±11years), and 46 with ES-only (39±11years), were compared using logistic regression analysis after adjusting for clustering effect.
  
  
  
  In the cohort with PNES/ES, ES antedated PNES in 28 patients (70%) and occurred simultaneously in 11 (27.5%), while PNES were the initial presentation in only 1 case (2.5%); disease duration was undetermined in 6. Compared with those with ES-only, patients with PNES/ES had higher depression and anxiety scores, shorter-duration electrographic seizures, less ES absence/staring semiology (all p≤0.01), and more ES arising in the right hemisphere, both in isolation and in combination with contralateral brain regions (61% vs. 41%; p=0.024, adjusted for anxiety and depression) and tended to have less ES arising in the left temporal lobe (13% vs. 28%; p=0.054). Compared with those with PNES-only, patients with PNES/ES tended to show fewer right-hemibody PNES events (7% vs. 23%; p=0.054) and more myoclonic semiology (10% vs. 2%; p=0.073).
  
  
  
  Right-hemispheric electrographic seizures may be more common among patients with ES who develop comorbid PNES, in agreement with prior neurobiological studies on functional neurological disorders.
authors.affiliation: Department of Neurology and Rehabilitative Medicine, University of Cincinnati, Cincinnati, OH, USA.
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Wissel
authors.affiliation: Division of Biostatistics & Epidemiology, Department of Biomedical Sciences, Texas Tech University Health Sciences Center, El Paso, TX, USA.
authors.forename: Alok K
authors.initials: AK
authors.lastname: Dwivedi
authors.affiliation: Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Tyler E
authors.initials: TE
authors.lastname: Gaston
authors.affiliation: Department of Neurology and Rehabilitative Medicine, University of Cincinnati, Cincinnati, OH, USA.
authors.forename: Federico J
authors.initials: FJ
authors.lastname: Rodriguez-Porcel
authors.affiliation: Division of Neurology, University of Toronto, Toronto, ON, Canada; Department of Neurology, King Fahad Hospital of the University, University of Dammam, Dammam, Saudi Arabia.
authors.forename: Danah
authors.initials: D
authors.lastname: Aljaafari
authors.affiliation: Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Hopp
authors.affiliation: Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: Allan
authors.initials: A
authors.lastname: Krumholz
authors.affiliation: Department of Neurology, Academisch Medisch Centrum Universiteit van Amsterdam, Amsterdam, Netherlands.
authors.forename: Sandra M A
authors.initials: SMA
authors.lastname: van der Salm
authors.affiliation: Division of Neurology, University of Toronto, Toronto, ON, Canada.
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Andrade
authors.affiliation: Division of Neurology, University of Toronto, Toronto, ON, Canada.
authors.forename: Felippe
authors.initials: F
authors.lastname: Borlot
authors.affiliation: Department of Neurology and Rehabilitative Medicine, University of Cincinnati, Cincinnati, OH, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Moseley
authors.affiliation: Department of Neurology and Rehabilitative Medicine, University of Cincinnati, Cincinnati, OH, USA.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Cavitt
authors.affiliation: Department of Clinical Neurosciences, The University of Edinburgh, Edinburgh, Scotland, United Kingdom.
authors.forename: Stevie
authors.initials: S
authors.lastname: Williams
authors.affiliation: Department of Clinical Neurosciences, The University of Edinburgh, Edinburgh, Scotland, United Kingdom.
authors.forename: Jon
authors.initials: J
authors.lastname: Stone
authors.affiliation: Department of Psychiatry and Neurology, Rhode Island Hospital, Brown University, Providence, RI, USA.
authors.forename: W Curt
authors.initials: WC
authors.lastname: LaFrance
authors.affiliation: Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Jerzy P
authors.initials: JP
authors.lastname: Szaflarski
authors.affiliation: Department of Neurology and Rehabilitative Medicine, University of Cincinnati, Cincinnati, OH, USA. Electronic address: alberto.espay@uc.edu.
authors.forename: Alberto J
authors.initials: AJ
authors.lastname: Espay
mesh_terms: D000328:Adult; D001007:Anxiety / Q000523:psychology; D016022:Case-Control Studies; D015331:Cohort Studies; D003863:Depression / Q000523:psychology; D004569:Electroencephalography; D004827:Epilepsy / Q000453:epidemiology*; D004833:Epilepsy, Temporal Lobe / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D012640:Seizures / Q000453:epidemiology* / Q000523:psychology; D013001:Somatoform Disorders / Q000453:epidemiology*
keywords: Epilepsy; Epileptic seizures; Functional disorders; Psychogenic nonepileptic seizures