Elsevier

Epilepsy & Behavior

Volume 62, September 2016, Pages 62-65
Epilepsy & Behavior

Video-EEG results and clinical characteristics in patients with psychogenic nonepileptic spells: The effect of a coexistent epilepsy

https://doi.org/10.1016/j.yebeh.2016.06.018Get rights and content

Highlights

  • The prevalence of coexisting epilepsy/PNES is 5.2% among all EMU admissions.

  • In EMU, PNES precede ES in 94% of patients with coexisting epilepsy/PNES.

  • PNES have different semiology than ES in the same patient.

  • Suggestibility precipitated PNES more often in patients without epilepsy.

  • Patients with epilepsy/PNES have more epilepsy risk factors.

Abstract

Rationale

Epilepsy and psychogenic nonepileptic spells (PNES) can coexist, often posing diagnostic and therapeutic challenges. We sought to identify clinical and historical characteristics of two groups of patients, those with coexisting epilepsy and PNES and those with PNES alone, and determine the prevalence of coexisting epilepsy/PNES with strict diagnostic criteria in a large group of epilepsy monitoring unit (EMU) patients.

Methods

We reviewed the medical records of all consecutive patients admitted to the Vanderbilt University Medical Center Adult EMU between July 1, 2007 and June 30, 2012. We identified patients with recorded PNES and classified them as having coexisting epilepsy/PNES or PNES alone and then systematically compared the clinical characteristics of these two groups.

Results

A total of 1567 patient medical records were reviewed. The prevalence rate of coexisting epilepsy/PNES was 5.2% among all EMU admissions (12.3% of all patients with epilepsy and 14.8% of all patients with PNES). These rates were lower when patients with interictal epileptiform activity (IEA) alone and no recorded ictal discharges were not included in the group with epilepsy (2.6%, 6.2%, and 7.4%, respectively). The accuracy of pre-EMU clinical suspicion was significantly higher in the group with PNES-only. Patients with epilepsy/PNES were significantly more likely to require more than one EMU admission for definitive diagnosis. The first PNES event preceded an epileptic seizure (ES) in 94.4% of patients with epilepsy/PNES. The group with PNES-only had significantly higher suggestibility, and the group with epilepsy/PNES had a significantly higher presence of epilepsy risk factors. Abnormal neurological examination and abnormal brain MRI were also significantly more common in the group with epilepsy/PNES.

Conclusions

Our study defined the prevalence of coexisting epilepsy/PNES in a large cohort with strict diagnostic criteria and outlined specific clinical and historical characteristics differentiating the two groups of patients with coexisting epilepsy/PNES and PNES-only. These findings should help guide clinicians to reach the correct diagnosis faster and provide appropriate treatment earlier.

Introduction

Epileptic seizures (ES) and psychogenic nonepileptic spells (PNES) can coexist, often posing diagnostic and therapeutic challenges. It is important to clinically identify the group of patients who have both epilepsy and PNES (epilepsy/PNES), as this can help initiate psychiatric and behavioral therapy in addition to antiepileptic treatment early on. It is also important for physicians in the epilepsy monitoring unit (EMU) to be extra vigilant about catching all types of spells when these patients are referred for EMU admission [1]. The seizures of patients with epilepsy who also have PNES can mistakenly be classified as refractory to medical treatment which could lead to polypharmacy, vagal nerve stimulator implantation, or even referral for epilepsy surgery [2], [3]. Identifying clinical and historical factors which can guide clinicians to suspect coexisting PNES in patients with epilepsy may prevent unnecessary aggressive treatments and help determine the most appropriate management including psychiatric care and cognitive behavioral therapy [4]. The prevalence of epilepsy in patients with PNES has been estimated to be between 5 and 50% [5]. This range is estimated between 10 and 30% when looking at EMU referrals alone [5], [6], [7], [8], [9], [10]. However, the majority of these studies were limited by small populations and variably defined criteria for the diagnosis of epilepsy or PNES [7], [11], [12], [13], [14], [15]. One large retrospective study found that 5.3% of the patients with PNES had coexisting epilepsy and proposed that the actual prevalence of this coexistence would be much lower if more strict criteria were applied for the diagnosis of epilepsy and PNES [10]. Another study comparing veterans and civilians found a 4% rate of coexisting epilepsy/PNES [16]. Prior studies focused on defining the prevalence of this coexistence but did not look for specific clinical and historical characteristics which could help clinicians suspect or detect this condition earlier. Our study was designed to determine the actual prevalence of epilepsy/PNES in the same patient and test the hypothesis that clinical and historical characteristics of these patients would differ from those of the patients who have PNES alone.

Section snippets

Material and methods

We retrospectively reviewed the medical records of all consecutive patients admitted to the Vanderbilt University Medical Center Adult EMU between July 1, 2007 and June 30, 2012. Medical record review included outpatient clinic notes, EMU admission notes, discharge summaries, and EMU reports with detailed descriptions of the clinical events and EEG correlation. All referred patients had either known epilepsy requiring seizure classification and/or focus localization or spells of unknown nature

Results

We reviewed a total of 1567 patients with a mean age of 40 years (SD: 14.5), 994 females (63.4%) and 573 males (36.6%). There were 581 (37.1%) patients with epilepsy only, 466 (29.7%) patients with PNES-only, 82 (5.2%) patients with epilepsy/PNES, and 18 (1.1%) patients with epilepsy + subjective spells (Fig. 1). The remaining 422 (26.9%) patients had only subjective events with normal EEG, nonepileptic physiologic events, or no events with normal or abnormal EEG. The group with PNES-only included

Discussion

Our goal was to identify the patients who had epilepsy/PNES from our EMU population and determine if certain clinical and historical features could help differentiate the patients with coexisting epilepsy/PNES from patients with PNES-only. We also aimed to more accurately determine the prevalence of epilepsy/PNES in the EMU setting. Although previous studies have estimated a wide range of prevalence for epilepsy/PNES among patients with PNES (5–50%), our study found that only 5.2% of the EMU

Conclusions

Patients with epilepsy/PNES have historically been a difficult group to study, as they make up a small percentage of patients we generally see in the EMU or outpatient setting. Our study confirms that some clinical and historical features can help differentiate the patients with epilepsy/PNES from those with PNES-only, but ultimately, identifying this group of patients remains a challenge, as evidenced by the multiple EMU admissions required to make a definitive diagnosis. Our study had the

Disclosure

None of the authors has any conflict of interest to disclose.

We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.

References (16)

There are more references available in the full text version of this article.

Cited by (20)

  • Psychogenic non-epileptic seizures in children

    2021, Current Problems in Pediatric and Adolescent Health Care
    Citation Excerpt :

    About 30% of children with the diagnosis of epilepsy have concomitant diagnosis of PNES; more common in younger children compared to adolescents in whom isolated PNES is more frequent.16,20 When children with PNES are evaluated as a group, about 5–12% may have epilepsy as a co-morbidity.19,21,22 The pediatric PNES population is a heterogenous population with varied semiology, identified stressors, and co-morbidities.

  • Semiology in Psychogenic Nonepileptic Seizures: Some Additional Facets

    2021, Journal of the Academy of Consultation-Liaison Psychiatry
  • Development and validation of a screening questionnaire for psychogenic nonepileptic seizures

    2020, Epilepsy and Behavior
    Citation Excerpt :

    Finally, we did not perform subgroup analyses in those that had a dual diagnosis of PNES and epilepsy or later-onset symptoms and excluded those with an intellectual disability. Evidence suggests that these groups may have unique psychological characteristics [46–48], and so further testing to examine the validity of the AASQ in these subgroups is required. Psychogenic nonepileptic seizures are difficult to diagnose and challenging to distinguish clinically from epilepsy, with contrasting implications for management.

  • The coexistence of psychogenic nonepileptic and epileptic seizures in the same patient is more frequent than expected: Is there any clinical feature for defining these patients?

    2020, Epilepsy and Behavior
    Citation Excerpt :

    In our epilepsy monitoring unit, in which adult Turkish patients from all over the country are admitted, the ratio of patients with PNES-epilepsy coexistence among all VEMU admissions (3.32%) and PNES-epilepsy coexistence ratio within all patients with PNES (32.51%) was consistent with the previous data. A previously reported prevalence of PNES-epilepsy coexistence within all VEMU patients was 5.2% [13]. The proportion of patients with PNES who also have epilepsy among patients with PNES has been estimated to vary between 5 and 50% [14].

  • Neuropsychiatric features of the coexistence of epilepsy and psychogenic nonepileptic seizures

    2018, Journal of Psychosomatic Research
    Citation Excerpt :

    Once a diagnosis of PNES is established, accurate treatment may lead to remission or improvement in 75–95% of patients, significantly reducing health care costs and overall morbidity [8,9]. Patients with co-existing ES and PNES are often excluded from PNES studies and in the last years only few studies differentiating patients with PNES-only from those with PNES + ES were published [10–15]. They were all retrospective and thus open to selection biases.

View all citing articles on Scopus
View full text