Psychological trauma, somatization, dissociation, and psychiatric comorbidities in patients with psychogenic nonepileptic seizures compared with those in patients with intractable partial epilepsy

Epilepsy Behav. 2019 Mar:92:108-113. doi: 10.1016/j.yebeh.2018.12.027. Epub 2019 Jan 15.


Objective: The objective of this study was to compare patients with intractable epilepsy with patients with psychogenic nonepileptic seizures (PNES) on the presence of psychological traumas, clinical factors, and psychological measures of somatization and dissociation.

Background: Several studies have reported a high prevalence of psychological trauma in patients with PNES, while less have examined the prevalence of psychological trauma in patients with epilepsy and compared both groups. Reports have been somewhat divergent with some describing significantly higher prevalence in physical abuse, others, in emotional abuse/neglect, and others, in sexual abuse in patients with PNES compared with those in patients with epilepsy.

Methods: This is a retrospective study of 96 patients (61 women, 35 men) with intractable epilepsy (2009 to 2017) and 161 patients (107 women, 54 men) with PNES (2008 to 2018). Demographic and clinical (psychological trauma, depression, anxiety, seizure frequency, and number of antiepileptic drugs) data were collected. The Trauma Symptom Inventory II and the Minnesota Multiphasic Personality Inventory 2RF were administered.

Results: Patients with PNES differed significantly from those with intractable epilepsy on sexual trauma (χ2 (5df, N = 257) =9.787, p < .002) and "other" trauma (χ2 (5df, N = 257) = 17.9076, p < .000). On psychological measures, there was a significant difference on Somatization scores in patients with PNES (M = 59.63, SD = 11.47) and patients with intractable epilepsy (M = 53.98, SD = 11.31); t(173) = 2.8396, p = .0051, but no difference was noted on a measure of Dissociation. Subsequent principal components analysis revealed that the first 3 principal components (sexual, physical, and other trauma) explained 74.19% of the variability, and that one principal component (dissociation, somatization, demoralization) explained 61.57% of the variability. However, after adjusting for the effects of covariates, only the presence of trauma discriminated between epilepsy and PNES.

Conclusions: Patients with PNES diagnoses differed from those with epilepsy on a Somatization scale but not on Dissociation or Intrusive Experiences and exhibited significantly higher rates of sexual and "other" trauma compared with those with intractable epilepsy. However, subsequent analyses revealed that a history of psychological trauma was the only condition found to discriminate between patients with PNES and those with epilepsy. These findings suggest that during initial workup and diagnosis, when patients report a history of psychological trauma (sexual or otherwise) a psychogenic nonepileptic etiology should be strongly considered in the differential diagnosis.

Keywords: Depression; Dissociation; Intractable epilepsy; Psychogenic nonepileptic seizures; Psychological trauma; Somatization.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Comorbidity
  • Diagnosis, Differential
  • Dissociative Disorders / diagnosis*
  • Dissociative Disorders / epidemiology
  • Dissociative Disorders / psychology
  • Drug Resistant Epilepsy / diagnosis*
  • Drug Resistant Epilepsy / epidemiology
  • Drug Resistant Epilepsy / psychology
  • Epilepsies, Partial / diagnosis*
  • Epilepsies, Partial / epidemiology
  • Epilepsies, Partial / psychology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Prevalence
  • Psychological Trauma / diagnosis*
  • Psychological Trauma / epidemiology
  • Psychological Trauma / psychology
  • Retrospective Studies
  • Seizures / diagnosis*
  • Seizures / epidemiology
  • Seizures / psychology
  • Somatoform Disorders / diagnosis*
  • Somatoform Disorders / epidemiology
  • Somatoform Disorders / psychology
  • Young Adult