Psychogenic non-epileptic seizures—Diagnostic issues: A critical review

Clinical characteristics of patients with refractory non-epileptic seizures

OBJECTIVES

This incidence of non-epileptic seizures (NES) is estimated at 1-35 per 100,000 population. While many patients achieve remission, a significant fraction of patients have a poor prognosis despite optimal interventions. This study reports on the characteristics of patients with refractory NES diagnosed and treated at a comprehensive epilepsy centre.

METHODS

A retrospective review of admissions to the Epilepsy Monitoring Unit identified patients diagnosed with NES over a 6-year period. Patients with refractory NES were identified through review of medical files. A diagnosis of refractory NES was assigned when patients experienced ongoing NES at least 1 year after diagnostic video-EEG monitoring. Data pertaining to predisposing, precipitating and perpetuating factors was collected on all patients and a comparative analysis was conducted between refractory and non-refractory cases.

RESULTS

66 patients with NES were identified, 35% were deemed refractory. There was no significant difference amongst predisposing factors between the groups. Psychosocial adversity and a clear precipitant proximate to the onset of NES were significantly more common in the refractory cohort. Unemployment at time of diagnosis was a significant perpetuating factor associated with poor outcome.

CONCLUSION

This study provides insight into the features associated with refractory NES and may serve to improve prognostication and management in this disabling condition.

Design and validation of a diagnostic suspicion checklist to differentiate epileptic from psychogenic nonepileptic seizures (PNES-DSC)

OBJECTIVE

Psychogenic non-epileptic seizures (PNES) are complex clinical manifestations and misdiagnosis as status epilepticus remains high, entailing deleterious consequences for patients. Video-electroencephalography (vEEG) remains the gold-standard method for diagnosing PNES. However, time and economic constraints limit access to vEEG, and clinicians lack fast and reliable screening tools to assist in the differential diagnosis with epileptic seizures (ES). This study aimed to design and validate the PNES-DSC, a clinically based PNES diagnostic suspicion checklist with adequate sensitivity (Se) and specificity (Sp) to discriminate PNES from ES.

METHODS

A cross-sectional study with 125 patients (n = 104 drug-resistant epilepsy; n = 21 PNES) admitted for a vEEG protocolised study of seizures. A preliminary PNES-DSC (16-item) was designed and used by expert raters blinded to the definitive diagnosis to evaluate the seizure video recordings for each patient. Cohen's kappa coefficient, leave-one-out cross-validation (LOOCV) and balance accuracy (BAC) comprised the main validation analysis.

RESULTS

The final PNES-DSC is a 6-item checklist that requires only two to be present to confirm the suspicion of PNES. The LOOCV showed 71.4% BAC (Se = 45.2%; Sp = 97.6%) when the expert rater watched one seizure video recording and 83.4% BAC (Se = 69.6%; Sp = 97.2%) when the expert rater watched two seizure video recordings.

CONCLUSION

The PNES-DSC is a straightforward checklist with adequate psychometric properties. With an integrative approach and appropriate patient history, the PNES-DSC can assist clinicians in expediting the final diagnosis of PNES when vEEG is limited. The PNES-DSC can also be used in the absence of patients, allowing clinicians to assess seizure recordings from smartphones.

Etiological Factors and Symptom Triggers in Functional Motor Symptoms and Functional Seizures: A Pilot Investigation

OBJECTIVE

This study examined etiological factors and symptom triggers of functional motor symptoms (FMS) or functional seizures (FS) and assessed potential relationships with relevant clinical features (i.e., functional symptoms, quality of life, and general functioning).

METHODS

Seventeen participants with FMS or FS and 17 healthy control participants underwent an in-depth clinical interview and completed questionnaires assessing adverse life events, psychological and physical symptoms, alexithymia, autistic traits, illness perceptions, health-related quality of life (HRQoL), and work and social functioning.

RESULTS

Participants with FMS or FS perceived various causes of the disorder, including physical symptoms (65%), emotional problems (53%), adverse life events (47%), and work-related factors (29%). Triggers of FMS and FS included physical activity or exertion (59%), stress and emotions (59%), sensory experiences (47%), and fatigue (41%). Compared with healthy control participants, participants with FMS or FS reported more adverse events during adolescence and higher levels of alexithymia, somatoform dissociation, psychological dissociation (disengagement, depersonalization, and derealization), anxiety, depression, and physical symptoms. Participants with FMS or FS had worse HRQoL than healthy control participants and impaired work and social functioning. There were inverse associations between HRQoL scores and somatoform dissociation, anxiety, and adverse life events.

CONCLUSIONS

Participants with FMS or FS reported diverse biopsychosocial etiological factors and symptom triggers. Ongoing psychological symptoms and lifetime adverse experiences were associated with worse HRQoL. Future studies will examine these factors in larger samples of individuals with FMS or FS to better understand their shared and distinct etiological underpinnings.

Effects of attachment styles, childhood traumas, and alexithymia in Turkish patients with epilepsy and functional seizures

INTRODUCTION

In this cross-sectional study, we used self-report scales to compare childhood traumas, attachment styles, and alexithymia among patients with functional seizures (FS) to patients with epilepsy and healthy controls. We also investigated risk factors associated with FS.

MATERIAL AND METHODS

A total of 44 patients with epilepsy, 14 patients with FS, and 25 healthy controls were included. All participants were over the age of 18 and were referred to the Baskent University Adana Epilepsy and Video-EEG Center. The patients underwent neurological examinations, brain MRIs, and video-EEG evaluations. Epileptic seizures were classified based on video EEG. The control group consisted of healthy individuals without neurological or psychiatric illness and a history of epileptic seizures or syncope. Beck Depression Inventory (BDI), Childhood Trauma Questionnaire (CTQ), Adult Attachment Scale (AAS), and Toronto Alexithymia Scale-20 (TAS-20) were applied to all participants.

RESULTS

Patients with FS had lower educational levels, higher rates of unemployment and single-marital status. The FS group had higher depression, childhood trauma, and alexithymia scores than the other groups. Furthermore, FS patients had a higher prevalence of avoidant attachment. The alexithymia and childhood trauma scores were both correlated with depression. Through the logistic regression analysis, childhood trauma scores and alexithymia were significant risk factors for FS.

CONCLUSION

The use of video-EEG for diagnosing FS can reduce the risk of misdiagnosis and inappropriate antiepileptic treatment. Psychiatric comorbidities, childhood traumas, and alexithymia are prevalent in patients with FS. Therefore, implementing a multidisciplinary treatment approach that addresses the psychological, medical, and social aspects of FS can significantly improve outcomes.

Psychiatric and psychological assessment of patients with drug-resistant epilepsy and psychogenic nonepileptic seizures (PNES) with no response to previous treatments

OBJECTIVE

Psychogenic nonepileptic seizures (PNES) are common imitators of epileptic seizures. Refractoriness to antiseizure medication hinders the differential diagnosis between ES and PNES, carrying deleterious consequences in patients with PNES. Psychiatric and psychological characteristics may assist in the differential diagnosis between drug-resistant epilepsy (DRE) and PNES. Nevertheless, current comprehensive psychiatric and psychological descriptive studies on both patient groups are scarce and with several study limitations. This study provides a comprehensive psychiatric and psychological characterization of Spanish patients with DRE and PNES.

METHOD

A cross-sectional and comparative study was completed with 104 patients with DRE and 21 with PNES. Psychiatric and psychological characteristics were assessed with the HADS, SCL-90-R, NEO-FFI-R, PDQ-4+, COPE, and QOLIE-31 tests. Parametric and non-parametric tests were used, and regression models were fit to further explore factors affecting patients' life quality.

RESULTS

Patients with PNES had greater levels of somatization and extraversion and were associated with benzodiazepine intake. Patients with DRE showed greater narcissistic personality disorder symptoms than those with PNES. In patients with DRE, difficulty in performing basic needs-related tasks and greater psychological distress severity and seizure frequency were associated with poorer life quality. In contrast, being a woman, having a psychiatric disorder history, and greater psychiatric symptoms' intensity were associated with poorer life quality in patients with PNES.

CONCLUSION

Patients with DRE and PNES share similar psychiatric and psychological characteristics, with only very few being significantly different.

Economic Cost of Functional Neurologic Disorders: A Systematic Review

BACKGROUND AND OBJECTIVES

Functional neurologic disorder (FND) represents genuine involuntary neurologic symptoms and signs including seizures, weakness, and sensory disturbance, which have characteristic clinical features, and represent a problem of voluntary control and perception despite normal basic structure of the nervous system. The historical view of FND as a diagnosis of exclusion can lead to unnecessary health care resource utilization and high direct and indirect economic costs. A systematic review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to assess these economic costs and to assess for any cost-effective treatments.

METHODS

We searched electronic databases (PubMed, PsycInfo, MEDLINE, EMBASE, and the National Health Service Economic Evaluations Database of the University of York) for original, primary research publications between inception of the databases and April 8, 2022. A hand search of conference abstracts was also conducted. Key search terms included "functional neurologic disorder," "conversion disorder," and "functional seizures." Reviews, case reports, case series, and qualitative studies were excluded. We performed a descriptive and qualitative thematic analysis of the resulting studies.

RESULTS

The search resulted in a total of 3,244 studies. Sixteen studies were included after screening and exclusion of duplicates. These included the following: cost-of-illness (COI) studies that were conducted alongside cohort studies without intervention and those that included a comparator group, for example, another neurologic disorder (n = 4); COI studies that were conducted alongside cohort studies without intervention and those that did not include a comparator group (n = 4); economic evaluations of interventions that were either pre-post cohort studies (n = 6) or randomized controlled trials (n = 2). Of these, 5 studies assessed active interventions, and 3 studies assessed costs before and after a definitive diagnosis of FND. Studies showed an excess annual cost associated with FND (range $4,964-$86,722 2021 US dollars), which consisted of both direct and large indirect costs. Studies showed promise that interventions, including provision of a definitive diagnosis, could reduce this cost (range 9%-90.7%). No cost-effective treatments were identified. Study comparison was limited by study design and location heterogeneity.

DISCUSSION

FND is associated with a significant use of health care resources, resulting in economic costs to both the patient and the taxpayer and intangible losses. Interventions, including accurate diagnosis, seem to offer an avenue toward reducing these costs.

A systems biology approach for discovering the cellular and molecular aspects of psychogenic non-epileptic seizure

Objectives

Psychogenic non-epileptic seizure (PNES) is the most common non-epileptic disorder in patients referring to epilepsy centers. Contrary to common beliefs about the disease's harmlessness, the death rate of PNES patients is similar to drug-resistant epilepsy. Meanwhile, the molecular pathomechanism of PNES is unknown with very limited related research. Thus, the aim of this in silico study was to find different proteins and hormones associated with PNES via a systems biology approach.

Methods

Different bioinformatics databases and literature review were used to find proteins associated with PNES. The protein-hormone interaction network of PNES was constructed to discover its most influential compartments. The pathways associated with PNES pathomechanism were found by enrichment analysis of the identified proteins. Besides, the relationship between PNES-related molecules and psychiatric diseases was discovered, and the brain regions that could express altered levels of blood proteins were discovered.

Results

Eight genes and three hormones were found associated with PNES through the review process. Proopiomelanocortin (POMC), neuropeptide Y (NPY), cortisol, norepinephrine, and brain-derived neurotrophic factor (BDNF) were identified to have a high impact on the disease pathogenesis network. Moreover, activation of Janus kinase-signaling transducer and activator of transcription (JAK-STAT) and JAK, as well as signaling of growth hormone receptor, phosphatidylinositol 3-kinase /protein kinase B (PI3K/AKT), and neurotrophin were found associated with PNES molecular mechanism. Several psychiatric diseases such as depression, schizophrenia, and alcohol-related disorders were shown to be associated with PNES predominantly through signaling molecules.

Significance

This study was the first to gather the biochemicals associated with PNES. Multiple components and pathways and several psychiatric diseases associated with PNES, and some brain regions that could be altered during PNES were suggested, which should be confirmed in further studies. Altogether, these findings could be used in future molecular research on PNES patients.

The value of ethical principles to reflect on emerging issues in epilepsy care and research

In the age of patient participation, ethics are more important than ever to help guide clinicians in situations of uncertainty. Principles of Biomedical Ethics by James F. Childress and Thomas L. Beauchamp remains the most important reference in medical ethics. In their work, they conceptualize four principles designed to help guide clinicians in decision making, notably beneficence, non-maleficence, autonomy, and justice. While using ethical principles dates back to at least Hippocrates, the introduction by Beauchamp and Childress of the principles of autonomy and justice have helped to deal with new challenges. This contribution will discuss how the principles can help elucidate issues of patient participation in epilepsy care and research using two case studies. METHODS: In this paper, we will discuss the equilibrium to be found between two principles (beneficence and autonomy) in the context of emerging debates in epilepsy care and research. The methods section details the specificities of each principle and their relevance to epilepsy care and research. RESULTS AND DISCUSSION: Using two case studies, we will explore the potential and limits of patient participation and how the ethical principles may help to provide nuance and reflection in this emerging debate. First of all, we will explore a clinical case which involves a conflictual situation with the patient and family about psychogenic nonepileptic seizures. We will then discuss an emerging issue in epilepsy research, namely the integration of persons with severe refractory epilepsy as patient research partners.

Global Epidemiology of Movement Disorders: Rare or Underdiagnosed?

In this manuscript, we review the epidemiology of movement disorders including Parkinson's disease (PD), atypical parkinsonism, essential tremor, dystonia, functional movement disorders, tic disorders, chorea, and ataxias. We emphasize age-, sex-, and geography-based incidence and prevalence, as well as notable trends including the rising incidence and prevalence of PD. Given the growing global interest in refining clinical diagnostic skills in recognizing movement disorders, we highlight some key epidemiological findings that may be of interest to clinicians and health systems tasked with diagnosing and managing the health of patients with movement disorders.

[Psychogenic non-epileptic seizures in autistic spectrum disorder]

Psychogenic non-epileptic seizures (PNES) are paroxysmal conditions that resemble epileptic seizures, but are not accompanied by epileptiform activity on the electroencephalogram and are not associated with other neurological or somatic disorders. Unrecognized PNES places a heavy burden on the patient and family, and on the health care system. Among many possible combinations of PNES with psychiatric disorders, autistic spectrum disorders are the least studied. This article presents a case of a 19-year-old female patient with autistic spectrum disorder and paroxysmal events and the presence of potentially epileptogenic changes in the brain. A multidisciplinary approach made it possible to diagnose PNEP in the patient.

Uses and abuses of the neuropsychological assessment in the presurgical evaluation of epilepsy surgery candidates

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Results from the neuropsychological assessment must be integrated into the wider clinical picture for all epilepsy surgery candidates.

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Motivation for surgery must be fully explored to ensure informed consent, even in ‘ideal’ surgical candidates.

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Inappropriate weight should not be given to standalone neuropsychological scores in the surgical decision making process.

Recent guidelines from the International League Against Epilepsy (ILAE) delineating the role of the neuropsychologist in the assessment of epilepsy surgery patients stress the collaborative contribution neuropsychologists should make to seizure characterization, lateralization and localization in the pre-surgical setting. The role they should play in the comprehensive counselling of surgical candidates, including exploration of the patient’s expectations of surgical treatment is also mandated. In this paper we present two contrasting case studies which illustrate the importance of these roles and the impact they can have on patient outcomes. In Case A we describe the patient journey of a 69-year-old women with left hippocampal sclerosis and concordant neurophysiology and seizure semiology. We present the series of discussions and decisions which led her to reject the surgical option following a detailed exploration of her motivations for surgery and the likely cognitive consequences of the procedure. In Case B we describe the series of errors and omissions which led to the failure of a clinical team to correctly interpret and integrate neuropsychological findings into the larger clinical picture of a 19-year-old woman with a seven year history of seizures. These errors ultimately culminated in the patient undergoing a right temporal lobe resection to treat psychogenic nonepileptic seizures (PNES).

The extent of integration of the data from the clinical neuropsychological assessment in the full presurgical evaluation was critical in determining the outcomes in both of these cases. Surgery did not solve Case B’s problems and left her with the lifelong cognitive vulnerabilities that are associated with unilateral temporal lobe resection. In contrast, Case A was a good surgical candidate, but comprehensive integration of the neuropsychological findings into the larger clinical picture established that surgery was not the best solution to the problem she wished to solve.

Mood Disturbances, Anxiety, and Impact on Quality of Life in Patients Admitted to Epilepsy Monitoring Units

Introduction: The overall combined prevalence of anxiety and depression in patients with epilepsy has been estimated at 20.2 and 22.9%, respectively, and is considered more severe in drug-refractory epilepsy. Patients admitted to epilepsy monitoring units constitute a particular group. Also, patients with psychogenic non-epileptic seizures can reach more than 20% of all admissions. This study aims to characterize these symptoms in a large cohort of patients admitted for evaluation in a tertiary epilepsy center.

Materials and Methods: The study was conducted among 493 consecutive patients (age: 38.78 ± 12.7, 57% females) admitted for long-term video EEG from January 2013 to February 2021. Demographic, clinical, and mood disorder patients' data were collected. Anxiety and depression symptoms were assessed through the Hospital Anxiety Depression Scale (HADS-A and HADS-D), the State Trait Anxiety Inventory (STAI), and Beck Depression Inventory (BDI-II). Quality of life was determined using the QOLIE-10. Patients were divided into three groups: patients with epilepsy (n = 395), psychogenic non-epileptic seizures (PNES) (n = 56), and combined (n = 33). A univariate and multivariate regression analysis was performed for variables associated with quality of life.

Results: Of 493 patients, 45.0% had structural etiology, and considering epilepsy classification, 43.6% were of temporal lobe origin. In addition, 32.45% of patients had a previous psychiatric history, 49.9% of patients had depressive symptoms in BDI, and 30.9% according to HADS-D; 56.42 and 52.63% of patients presented pathological anxiety scores in STAI-T and STAI-S, respectively; and 44.78% according to HADS-A. PNES and combined groups revealed a higher incidence of pathologic BDI scores (64.29 and 78.79%, p < 0.001) as well as pathologic HADS-A scores (p = 0.001). Anxiety and depression pathologic results are more prevalent in females, HADS-A (females = 50.7%, males = 36.8%; p = 0.0027) and BDI > 13 (females = 56.6%, males = 41.0%; p = 0.0006). QOLIE-10 showed that 71% of the patients had their quality of life affected with significantly higher scores in the combined group than in the epilepsy and PNES groups (p = 0.0015).

Conclusions: Subjective anxiety, depression, and reduced quality of life are highly prevalent in patients with refractory epilepsy. These symptoms are more evident when PNES are associated with epilepsy and more severe among female patients. Most of the cases were not previously diagnosed. These factors should be considered in everyday clinical practice, and specific approaches might be adapted depending on the patient's profile.

Towards a sociological understanding of medical gaslighting in western health care

In recent years, the term 'medical gaslighting' and accompanying accounts of self-identified women experiencing invalidation, dismissal and inadequate care have proliferated in the media. Gaslighting has primarily been conceptualized in the field of psychology as a phenomenon within interpersonal relationships. Following the work of Paige Sweet (American Sociological Review, 84, 2019, 851), I argue that a sociological explanation is necessary. Such an explanation illustrates how medical gaslighting is not simply an interpersonal exchange, but the result of deeply embedded and largely unchallenged ideologies underpinning health-care services. Through an intersectional feminist and Foucauldian analysis, I illuminate the ideological structures of western medicine that allow for medical gaslighting to be commonplace in the lives of women, transgender, intersex, queer and racialized individuals seeking health care. Importantly, these are not mutually exclusive groups, and I use the term bio-Others to highlight and connect how those with embodied differences are treated in medicine. This article indicates the importance of opening a robust discussion about the sociology of medical gaslighting, so that we might better understand what structural barriers people of marginalized social locations face in accessing quality health care and develop creative solutions to challenge health-care inequities.

Psychogenic non-epileptic seizures (PNES) in the context of concurrent epilepsy – making the right diagnosis

Epilepsy is a risk factor for the development of psychogenic non-epileptic seizures (PNES) and comorbid epilepsy is recognized as a comorbidity in about 10–30% of patients with PNES. The combination of epileptic and nonepileptic seizures poses a particular diagnostic challenge. In patients with epilepsy, additional PNES may be suspected on the basis of their typical semiology. The possibility of additional PNES should also be considered if seizures fail to respond to antiepileptic drug treatment, in patients with frequent emergency admissions with seizures and in those who develop new types of seizures. The description of semiological details by patients and witnesses can suggest additional PNES. Home video recordings can support an initial diagnosis, however, especially in patients with mixed seizure disorders it is advisable to seek further diagnostic confirmation by capturing all habitual seizure types with video-EEG. The clinical features of PNES associated with epilepsy are similar to those in isolated PNES disorders and include longer duration, fluctuating course, asynchronous movements, pelvic thrusting, side-to-side head or body movement, persistently closed eyes and mouth, ictal crying, recall of ictal experiences and absence of postictal confusion. PNES can also present as syncope-like episodes with unresponsiveness and reduced muscle tone. There is no unique epileptological or brain pathology profile putting patients with epilepsy at risk of additional PNES. However, patients with epilepsy and PNES typically have lower educational achievements and higher levels of psychiatric comorbidities than patients with epilepsy alone. Psychological trauma, including sexual abuse, appears to be a less relevant aetiological factor in patients with mixed seizure disorders than those with isolated PNES, and the gender imbalance (i.e. the greater prevalence in women) is less marked in patients with PNES and additional epilepsy than those with PNES alone. PNES sometimes develop after epilepsy surgery. A diagnosis of ‘known epilepsy’ should never be accepted without (at least brief) critical review. This narrative review summarises clinical, electrophysiological and historical features that can help identify patients with epilepsy and additional PNES.

Effective connectivity between emotional and motor brain regions in people with psychogenic nonepileptic seizures (PNES)

OBJECTIVE

To characterize the effective connectivity (EC) between the emotion and motor brain regions in patients with psychogenic nonepileptic seizures (PNES), based on resting-state spectral dynamic causal modeling (spDCM).

METHODS

Twenty-three patients with PNES and twenty-five healthy control (HC) subjects underwent resting-state fMRI scanning. The coupling parameters indicating the causal interactions between eight brain regions associated with emotion, executive control, and motion were estimated for both groups, using resting-state fMRI spDCM.

RESULTS

Compared to the HC subjects, in patients with PNES: (i) the left insula (INS) and left and right inferior frontal gyri (IFG) are more inhibited by the amygdala (AMYG), anterior cingulate cortex (ACC), and precentral gyrus (PCG); (ii) the left AMYG has greater inhibitory effects on the INS, IFG, dorsolateral prefrontal cortex (DLPFC), PCG, and supplementary motor area (SMA); (iii) the left ACC has more inhibitory effects on the INS and IFG; (iv) the right ACC is more inhibited by the INS and IFG, and has a less inhibitory effect on the SMA and PCG; and (v) the left caudate (CAU) had increased inhibitory effects on the AMYG and IFG and a more excitatory effect on the SMA.

CONCLUSION

Our results suggest that in patients with PNES, the emotion-processing regions have inhibitory effects on the executive control areas and motor regions. Our findings may provide further insight into the influence of emotional arousal on functional movements and the underlying mechanisms of involuntary movements during functional seizures. Furthermore, they may suggest that emotion regulation through cognitive behavioral psychotherapies can be a potentially effective treatment modality.

Long-term Home Video EEG for Recording Clinical Events

SUMMARY

Around 50 years after the first EEG acquisition by Hans Berger, its use in ambulatory setting was demonstrated. Ever since, ambulatory EEG has been widely available and routinely used in the United States (and to a lesser extent in Europe) for diagnosis and management of patients with epilepsy. This technology alone cannot help with semiological characterization, and absence of video is one of its main drawbacks. Addition of video to ambulatory EEG potentially improves diagnostic yield and opens new aspects of utility for better characterization of patient's events, including differential diagnosis, classification, and quantification of seizure burden. Studies evaluating quality of ambulatory video EEG (aVEEG) suggest good quality recordings are feasible. In the utilization of aVEEG, to maximize yield, it is important to consider pretest probability. Having clear pretest questions and a strong index of suspicion for focal, generalized convulsive or non-epileptic seizures further increases the usefulness of aVEEG. In this article, which is part of the topical issue "Ambulatory EEG," the authors compare long-term home aVEEG to inpatient video EEG monitoring, discuss aVEEG's use in diagnosis and follow-up of patients, and present the authors' own experience of the utility of aVEEG in a teaching hospital setting.

Brain functional connectivity in individuals with psychogenic nonepileptic seizures (PNES): An application of graph theory

OBJECTIVE

To determine brain functional connectivity (FC), based on the graph theory, in individuals with psychogenic nonepileptic seizures (PNES), in order to better understand the mechanisms underlying this disease.

METHODS

Twenty-three patients with PNES and twenty-five healthy control subjects were examined. Alterations in FC within the whole brain were examined using resting-state functional magnetic resonance imaging (MRI). We calculated measures of the nodal degree, a major feature of the graph theory, for all the cortical and subcortical regions in the brain. Pearson correlation was performed to determine the relationship between nodal degree in abnormal brain regions and patient characteristics.

RESULTS

The nodal degrees in the right caudate (CAU), left orbital part of the left inferior frontal gyrus (ORBinf), and right paracentral lobule (PCL) were significantly greater (i.e. hyper-connectivity) in individuals with PNES than in healthy control subjects. On the other hand, a lesser nodal degree (i.e. hypo-connectivity) was detected in several other brain regions including the left and right insula (INS), as well as the right putamen (PUT), and right middle occipital gyrus (MOG).

CONCLUSION

Our findings suggest that the FC of several major brain regions can be altered in individuals with PNES. Areas with hypo-connectivity may be involved in emotion processing (e.g., INS) and movement regulation (e.g., PUT), whereas areas with hyper-connectivity may play a role in the inhibition of unwanted movements and cognitive processes (e.g., CAU).

Epidemiology of Functional Seizures Among Adults Treated at a University Hospital

Importance

Functional seizures (formerly psychogenic nonepileptic seizures), paroxysmal episodes that are often similar to epileptic seizures in their clinical presentation and display no aberrant brain electrical patterns, are understudied. Patients experience a long diagnostic delay, few treatment modalities, a high rate of comorbidities, and significant stigma due to the lack of knowledge about functional seizures.

Objective

To characterize the clinical epidemiology of a population of patients with functional seizures observed at Vanderbilt University Medical Center (VUMC).

Design, Setting, and Participants

This case-control study included patients with functional seizures identified in the VUMC electronic health record (VUMC-EHR) system from October 1989 to October 2018. Patients with epilepsy were excluded from the study and all remaining patients in the VUMC medical center system were used as controls. In total, the study included 1431 patients diagnosed with functional seizures, 2251 with epilepsy and functional seizures, 4715 with epilepsy without functional seizures, and 502 200 control patients who received treatment at VUMC for a minimum of a 3 years. Data were analyzed from November 2018 to March 2020.

Exposure

Diagnosis of functional seizures, as identified from the VUMC-EHR system by an automated phenotyping algorithm that incorporated International Classification of Diseases, Ninth Revision (ICD-9) codes, International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) codes, Current Procedural Terminology codes, and natural language processing.

Main Outcomes and Measures

Associations of functional seizures with comorbidities and risk factors, measured in odds ratios (ORs).

Results

Of 2 346 808 total patients in the VUMC-EHR aged 18 years or older, 3341 patients with functional seizures were identified (period prevalence, 0.14%), 1062 (74.2%) of whom were women and for which the median (interquartile range) age was 49.3 (39.4-59.9) years. This assessment replicated previously reported associations with psychiatric disorders including posttraumatic stress disorder (PTSD) (OR, 1.22; 95% CI, 1.21-1.24; P < 3.02 × 10-5), anxiety (OR, 1.14; 95% CI, 1.13-1.15; P < 3.02 × 10-5), and depression (OR, 1.14; 95% CI, 1.13-1.15; P < 3.02 × 10-5), and identified novel associations with cerebrovascular disease (OR, 1.08; 95% CI, 1.06-1.09; P < 3.02 × 10-5). An association was found between functional seizures and the known risk factor sexual assault trauma (OR, 10.26; 95% CI, 10.09-10.44; P < 3.02 × 10-5), and sexual assault trauma was found to mediate nearly a quarter of the association between female sex and functional seizures in the VUMC-EHR.

Conclusions and Relevance

This case-control study found evidence to support previously reported associations, discovered new associations between functional seizures and PTSD, anxiety, and depression. An association between cerebrovascular disease and functional seizures was also found. Results suggested that sexual trauma may be a mediating factor in the association between female sex and functional seizures.

White matter and neurite morphology differ in psychogenic nonepileptic seizures

OBJECTIVE

To further evaluate the relationship between the clinical profiles and limbic and motor brain regions and their connecting pathways in psychogenic nonepileptic seizures (PNES). Neurite Orientation Dispersion and Density Indices (NODDI) multicompartment modeling was used to test the relationships between tissue alterations in patients with traumatic brain injury (TBI) and multiple psychiatric symptoms.

METHODS

The sample included participants with prior TBI (TBI; N = 37) but no PNES, and with TBI and PNES (TBI + PNES; N = 34). Participants completed 3T Siemens Prisma MRI high angular resolution imaging diffusion protocol. Statistical maps, including fractional anisotropy (FA), mean diffusivity (MD), neurite dispersion [orientation dispersion index (ODI)] and density [intracellular volume fraction (ICVF), and free water (i.e., isotropic) volume fraction (V-ISO)] signal intensity, were generated for each participant. Linear mixed-effects models identified clusters of between-group differences in indices of white matter changes. Pearson's r correlation tests assessed any relationship between signal intensity and psychiatric symptoms.

RESULTS

Compared to TBI, TBI + PNES revealed decreases in FA, ICVF, and V-ISO and increases in MD for clusters within cingulum bundle, uncinate fasciculus, fornix/stria terminalis, and corticospinal tract pathways (cluster threshold α = 0.05). Indices of white matter changes for these clusters correlated with depressive, anxiety, PTSD, psychoticism, and somatization symptom severity (FDR threshold α = 0.05). A follow-up within-group analysis revealed that these correlations failed to reach the criteria for significance in the TBI + PNES group alone.

INTERPRETATION

The results expand support for the hypothesis that alterations in pathways comprising the specific PNES network correspond to patient profiles. These findings implicate myelin-specific changes as possible contributors to PNES, thus introducing novel potential treatment targets.

Psychological inflexibility and somatization in nonepileptic attack disorder

BACKGROUND

There is no clear understanding of what causes and maintains nonepileptic attack (NEA) disorder (NEAD), or which psychological therapies may be helpful. The relationships between variables of psychological inflexibility: experiential avoidance (EA), cognitive fusion (CF), mindfulness, and key outcome variables in NEAD: somatization, impact upon life, and NEA frequency were investigated.

METHOD

Two hundred eighty-five individuals with NEAD completed validated measures online. Linear regression was used to explore which variables predicted somatization and impact upon life. Ordinal regression was used to explore variables of interest in regard to NEA frequency.

RESULTS

Mindfulness, EA, CF, somatization, and impact upon life were all significantly correlated. Mindfulness uniquely predicted somatization when considered in a model with EA and CF. Higher levels of somatization increased the odds of experiencing more NEAs. Individuals who perceived NEAD as having a more significant impact upon their lives had more NEAs, more somatic complaints, and more EA.

CONCLUSIONS

Higher levels of CF and EA appear to be related to lower levels of mindfulness. Lower levels of mindfulness predicted greater levels of somatization, and somatization predicted NEA frequency. Interventions that tackle avoidance and increase mindfulness, such as, acceptance and commitment therapy, may be beneficial for individuals with NEAD. Future directions for research are suggested as the results indicate more research is needed.

Skin conductance response and emotional response in women with psychogenic non-epileptic seizures

PURPOSE

Recent etiopathogenic models place emotional dysregulation at the core of psychogenic nonepileptic seizure (PNES). Our purpose was to assess physiological, cognitive, and behavioral emotional responses of PNES patients.

METHODS

This study compared three types of emotional responses to visual emotional stimuli between 34 female PNES group and 34 matched healthy controls: physiological response measured by skin conductance response (SCR) (rate, amplitude and latency) and heart rate deceleration; cognitive response measured by valence and arousal elicited by the images; and behavioural response measured by latency of ratings. The groups were characterized on psychiatric comorbidities, traumatic history, alexithymia, and dissociation.

RESULTS

Compared to controls, PNES group displayed lower SCR for all images (p = 0.038), shorter amplitude of heart rate deceleration (p = 0.024) and faster arousal rating for all images (p = 0.019), but no difference on cognitive rating of images. Within-groups analyses showed only in PNES subjects increased rate (+19.35%, p = 0.046) SCR for negative stimuli with strong arousal compared to negative with low arousal. PNES physiological response (SCR and heart rate deceleration) was negatively correlated to dissociation tendency (r=-0.48, p = 0.0083) and alexithymia (r=-0.44, p = 0.012)). For cognitive response, no correlation was found.

CONCLUSION

These results are in favour of a lower physiological emotional response but with an over-reactivity at behavioral level contrasting with similar cognitive assessment. For strong aversive stimuli, PNES might present a trend to overreact at physiological and behavioural levels. Our results suggest that dissociation and difficulty in describing feelings are associated with an altered physiological response in PNES women only.

Differential Semiology Based on Video Electroencephalography Monitoring Between Psychogenic Nonepileptic Seizures and Temporal Lobe Epileptic Seizures

BACKGROUND

Psychogenic nonepileptic seizures (PNESs) are disruptive changes in behavior without ictal correlate of epileptic activity and high prevalence of psychiatric morbidity. Differential diagnosis is difficult particularly with temporal lobe epilepsy (TLE), which is also associated with high prevalence of psychiatric comorbidity. Although video electroencephalography is the gold standard for differential diagnosis, clinical semiology analysis may help the clinician in general medical practice.

OBJECTIVE

In this study, the differential semiology, based on video electroencephalography, between PNESs and TLE seizures was analyzed.

METHODS

The video electroencephalography of patients with diagnosis of PNES and TLE were reviewed and compared between groups. Clinical semiology of all episodes recorded by video electroencephalography in each patient was analyzed and classified in accordance with the presence of behavioral arrest, motor hyperkinetic activity, impaired awareness, aura, and automatisms. Chi square test and binary logistic regression were determined.

RESULTS

Thirty-two patients with PNES (32 ± 11 y) and 34 with TLE (32 ± 12 y) were included. Female patients were predominant in the PNES group (P < 0.05). Mean time duration of episodes was 6.8 ± 10 minutes in PNES and 1.6 ± 0.8 minutes in TLE (P < 0.05). Impaired awareness (odds ratio = 24.4; 95% confidence interval = 3.79 -157.3, P < 0.01), automatisms (odds ratio = 13.9; 95% confidence interval = 2.1- 90.5, P < 0.01), and shorter duration of the events (odds ratio = 2.261, 95% confidence interval = 1.149 - 4.449, P = 0.018) were found as independent factors for detecting TLE seizures comparing PNESs.

CONCLUSION

Clinical semiology analysis may orientate the differential diagnosis in general medical practice, between PNESs and TLE seizures. Further studies comparing PNES semiology with other subtypes of epilepsies may complete these preliminary findings.

A Previously Healthy Adolescent With Acute Psychosis and Severe Hyperhidrosis

A previously healthy 15-year-old boy presented with 3 months of progressive psychosis, insomnia, back and groin pain, and hyperhidrosis. On examination, the patient was disheveled, agitated, and soaked with sweat, with systolic blood pressure in the 160s and heart rate in the 130s. Aside from occasional auditory and visual hallucinations, his neurologic examination was normal. The patient was admitted for an extensive workup, including MRI of the brain and spine and lumbar puncture, which were normal. Through collaboration with various pediatric specialists, including psychiatry and neurology, a rare diagnosis was ultimately unveiled.

Personality traits, illness behaviors, and psychiatric comorbidity in individuals with psychogenic nonepileptic seizures (PNES), epilepsy, and other nonepileptic seizures (oNES): Differentiating between the conditions

OBJECTIVES

The study aimed to investigate if South African individuals with psychogenic nonepileptic seizures (PNES) differ from individuals with epileptic seizures (ES) and other nonepileptic seizures (oNES) in terms of demographic and seizure characteristics, personality traits, illness behaviors, and depression, anxiety, and posttraumatic stress disorder (PTSD) comorbidity in statistically significant ways; and if so, to test if these differences can be utilized in raising suspicion of PNES as the differential diagnosis to epilepsy and oNES in practice.

METHODS

Data were analyzed from 29 adults with seizure complaints recruited using convenience sampling from a private and a government hospital with video-electroencephalography (vEEG) technology. A quantitative double-blind convenient sampling comparative design was used. A demographic and seizure questionnaire, the NEO Five Factor Inventory-3 (NEO-FFI-3), an abbreviated version of Illness Behavior Questionnaire (IBQ), and the Beck Anxiety Inventory - Primary Care (BAI-PC) were administered. Cronbach's alphas, analysis of variance (ANOVA), cross-tabulation, Fisher exact test, and receiver operating characteristic (ROC) analyses were performed on the dataset.

RESULTS

The total sample consisted of 29 participants, of which 5 had PNES (17%), 21 ES (73%), and 3 oNES (10%). The final sample was comprised of 24 participants from the private hospital and 5 from the government hospital. The group with PNES was found to be significantly more male, to experience significantly more monthly seizures, and chronic pain when comparing the PNES with the ES group, and the PNES with the combined ES and oNES group in both private only sample, as well as the private and government hospital combined sample. Patients with PNES also had a higher level of education compared with the group with ES in the combined private and government hospital sample, something that was not evident in the private hospital only sample. No significant differences between groups were found in either sample in terms of age, population group, language, age at first seizure, and the NEO-FFI-3 subscales. All three groups scored above the cutoff point of 5 exhibiting depression, anxiety, and PTSD symptoms on the BAI-PC in both samples. However, the group with PNES tended to score significantly higher than the group with ES and the combined ES and oNES group in the private hospital sample. A cutoff point of 12 on the BAI-PC was found to predict PNES in this seizure population with 80% sensitivity and 89% specificity. However, once the analysis was repeated on the combined private and government hospital sample, significance in BAI-PC scores between groups was lost. All scales showed good reliability in our study, with the exception of the "Openness to Experience" subscale of the NEO-FFI-3 once reliability analysis was carried out on the combined private and government hospital group.

CONCLUSIONS

This study provides an important stepping stone in the understanding of demographic and seizure factors, personality domains, abnormal illness behaviors, and psychiatric comorbidity in the South African population with PNES. The study also reported on a cutoff score of 12 on the BAI-PC predicting PNES with 80% sensitivity and 89% specificity in a private hospital sample.

Structured testing during seizures: A practical guide for assessing and interpreting ictal and postictal signs during video EEG long term monitoring

BACKGROUND

Ictal and postictal testing carried out in long-term epilepsy monitoring units is often sub-optimal. Recently, a European consensus protocol for testing patients during and after seizures was developed by a joint taskforce of the International League Against Epilepsy - Commission on European Affairs and the European Epilepsy Monitoring Unit Association.

AIM

Using this recently developed standardised assessment battery as a framework, the goal of this narrative review is to outline the proposed testing procedure in detail and explain the rationale for each individual component, focusing on the underlying neurobiology. This is intended to serve as an educational resource for staff working in epilepsy monitoring units.

METHODS

A literature review of PubMed was performed; using the search terms "seizure", "ictal", "postictal", "testing", "examination", and "interview". Relevant literature was reviewed and relevant references were chosen. The work is presented as a narrative review.

RESULTS

The proposed standardised assessment battery provides a comprehensive and user-friendly format for ictal-postictal testing, and examines consciousness, language, motor, sensory, and visual function.

CONCLUSION

The standardised approach proposed has the potential to make full use of data recorded during video EEG increasing the diagnostic yield with regards to lateralisation and localisation, aiding both presurgical and diagnostic studies.

A case of dissociative convulsions presented as frequent epilepsy-like seizures

Dissociative convulsions, a prominent form of dissociative (conversion) disorder formerly known as hysteria, are a common and elusive differential diagnosis from epilepsy. However, the treatment of such patients is always challenging and frustrating due to poor response to the routinely used interventions in most situations. Here, we present a case with dissociative convulsions in order to catch the eye of the clinicians and researchers on the recognition of clinical manifestation and exploration of therapeutic strategies.

Preliminary Evidence for Limbic-Frontal Hyperexcitability in Psychogenic Nonepileptic Seizure Patients

OBJECTIVES

The goal of the current pilot project was to probe the resting-state magnetoencephalography (MEG) in individuals with psychogenic nonepileptic seizures (PNES) and ascertain if there is evidence for frontal temporal cortical hyperexcitability, as evidenced by increased focal coherence in these regions.

METHODS

Six patients with PNES and without any evidence of epilepsy were included. Nine healthy control (HC) subjects (age matched as a group) were also included. Subjects underwent 10 minutes of eyes open and 10 minutes of eyes closed MEG recording without any specific cognitive tasks (ie, resting state).

RESULTS

Analysis shows posterior-occipital alpha power to be decreased but fronto-temporal delta/theta power increased in people with PNES compared with HC subjects. Analyses of mean interregional functional connectivity of 54 brain regions, patients with PNES tended to have reduced mean coherence in extra-fronto-temporal regions (ex-FTRs) while increased mean coherence in fronto-temporal regions (FTRs) compared with HC. Furthermore, all 6 patients with PNES had their highest coherence structure within the FTRs. This is in contrast to the HC subjects where only 3 of the 9 subjects had their highest coherence value structure in the FTRs (χ² = 6.67, P = .010).

CONCLUSIONS

The above findings are consistent with a disbalance between frontotemporal and posterior brain regions in this population with possible increased excitability in the FTRs. The data support the need for further investigations of the pathophysiology of PNES. The identification of a biomarker for PNES would not only provide for more informed therapeutic approaches, but it could also eliminate the stigma associated with the diagnosis of PNES.

Adult EEG

After more than 85 years of development and use in clinical practice, the electroencephalogram (EEG) remains a dependable, inexpensive, and useful diagnostic tool for the investigation of the electrophysiologic activity of the brain. The advent of digital technology has led to greater sophistication and multiple software applications to extend the utility of EEG beyond the confines of the laboratory. Despite the discovery of new waveforms, basic neurophysiologic principles remain essential to the clinical care of patients. Patterns in the interictal EEG make it possible to clarify the differential diagnosis of paroxysmal neurological events, classify seizure type and epilepsy syndromes, and characterize and quantify seizures when ictal recordings are obtained. EEG can also demonstrate cerebral dysfunction when structural imaging is normal to detect focal or lateralized abnormalities in patients with encephalopathy. High-density EEG with electrical source imaging has improved localization in candidates for epilepsy surgery. Quantitative EEG and broadband EEG are advancing our understanding of the functional processes of the brain itself.

Differentiating epilepsy from psychogenic nonepileptic seizures using neuropsychological test data

OBJECTIVE

Differentiating epileptic seizures (ES) from psychogenic nonepileptic seizures (PNES) represents a challenging differential diagnosis with important treatment implications. This study was designed to explore the utility of neuropsychological test scores in differentiating ES from PNES.

METHOD

Psychometric data from 72 patients with ES and 33 patients with PNES were compared on various tests of cognitive ability and performance validity. Individual measures that best discriminated the diagnoses were then entered as predictors in a logistic regression equation with group membership (ES vs. PNES) as the criterion.

RESULTS

On most tests of cognitive ability, the PNES sample outperformed the ES sample (medium-large effect) and was less likely to fail the Reliable Digit Span. However, patients with PNES failed two embedded validity indicators at significantly higher rates (risk ratios (RR): 2.45-4.16). There were no group differences on the Test of Memory Malingering (TOMM). A logistic regression equation based on seven neuropsychological tests correctly classified 85.1% of patients. The cutoff with perfect specificity was associated with 0.47 sensitivity.

CONCLUSIONS

Consistent with previous research, the utility of psychometric methods of differential diagnosis is limited by the complex neurocognitive profiles associated with ES and PNES. Although individual measures might help differentiate ES from PNES, multivariate assessment models have superior discriminant power. The strongest psychometric evidence for PNES appears to be a consistent lack of impairment on tests sensitive to diffuse neurocognitive deficits such as processing speed, working memory, and verbal fluency. While video-electroencephalogram (EEG) monitoring is the gold standard of differential diagnosis, psychometric testing has the potential to enhance clinical decision-making, particularly in complex or unclear cases such as patients with nondiagnostic video-EEGs. Adopting a standardized, fixed neuropsychological battery at epilepsy centers would advance research on the differential diagnostic power of psychometric testing.

Characteristics of patients with confirmed epilepsy and psychogenic nonepileptic seizures in Qatar

OBJECTIVE

The Middle Eastern country of Qatar opened its first epilepsy monitoring unit (EMU) in late 2015. This study compared demographic and clinical characteristics of patients with confirmed epilepsy to those of patients with confirmed psychogenic nonepileptic seizures (PNES).

METHODS

Data were collected via retrospective chart review on 113 patients admitted for evaluation to the Qatar national health system EMU between November 2015 and May 2017.

RESULTS

Seventy-one patients had a confirmed diagnosis (20 had PNES, 46 had epilepsy, 5 had both PNES and epilepsy). Evaluation in 33 patients was inconclusive, and 9 had other medical conditions. Patients with PNES were significantly more likely to be primary Arabic speakers (p = 0.003), and this difference was not explained by education or employment status. The most common referral request in patients with PNES was for recurrent/refractory seizures (p = 0.011), and there was a trend for patients with PNES to have more frequent seizures compared with patients with epilepsy (daily to several per week versus several times a month or less, p = 0.051). Depression was identified in 47% of patients with epilepsy and 65% of patients with PNES, and patients with PNES had higher mean depression scores on the PHQ-9 than patients with epilepsy (p = 0.014). Patients with PNES experienced significantly more fatigue (p = 0.021). Seventy percent of patients with PNES and 50% of patients with epilepsy reported sleep problems.

CONCLUSIONS

The characteristics of patients with epilepsy and PNES at the EMU in Qatar were generally similar to those found worldwide. Patients with PNES more often suffered from frequent depression, sleep problems, and fatigue than those with epilepsy, but these were significant concerns for both groups.

Research on dissociative seizures: A bibliometric analysis and visualization of the scientific landscape

Dissociative seizures are a common and often elusive differential diagnosis in epilepsy centers. Considering their high prevalence, long diagnostic delays, and disappointing rates of treatment response, scientific research dedicated to dissociative seizures is surprisingly scarce. In order to chart the scientific landscape of dissociative seizures and to visualize thematic clusters and trends in research, a comprehensive bibliometric analysis was performed. The Web of Science database was examined to identify relevant English language documents from the last half-century. A total of 1751 documents with titles referring to dissociative seizures were identified. Automated textual analysis of all titles and abstracts revealed that research clusters around three major topics: differential diagnosis in epilepsy centers, management and treatment, and psychopathology. Time analysis of term networks revealed that the focus of clinical research has moved from diagnostic procedures to treatment approaches. Furthermore, interest within etiological research is shifting from an emphasis on early life trauma and personality traits to the role of anxiety and emotion regulation. With respect to individual contributing authors, a relatively small network of prolific scientists with a remarkable degree of collaboration emerges. By mapping relevant publications, it becomes evident that dissociative seizures still represent a subject mostly within the realm of neurology and epileptology, with a tendency to settle in the latter domain. This analysis sheds light on an important niche subject and highlights trends in research focus and output.

Suicide risk, temperament traits, and sleep quality in patients with refractory epilepsy

OBJECTIVES

The objective of the study was to access the suicide risk (SR) in patients with refractory epilepsy and its association with temperament and sleep quality.

METHODS

A total of 50 consecutive patients referred for epilepsy surgery evaluation in the Porto Alegre Epilepsy Surgery Program were included. All patients had a detailed neurologic and psychiatric evaluation, including video-electroencephalogram (VEEG), high-resolution magnetic ressonance imaging (MRI), and neuropsychologic assessment. In addition, structured questionnaires were applied: module C of the MINI-plus (International Neuropsychiatric Interview-Brazilian version 5.0.0), Affective and Emotional Composite Temperament Scale (AFECTS), and Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Ten patients (20.0%) showed an increased SR. The most frequent location of the epileptic focus was in the temporal lobe (50%; n=25). Final diagnosis on VEEG comprised epilepsy in 74.0% (n=37), psychogenic nonepileptic seizures (PNES) in 8.0% (n=4), and both in 12%. Thirty patients (60.0%) received surgery indication. Mood disorders were the main psychiatric diagnosis, found in 19 subjects (70.4%), with major depressive disorder (MDD) encountered in 15 patients (55.6%). In the group, SR was more frequent in patients with sleep disorders (p=0.001) and elevated scores of high emotional sensitivity (p=0.003).

CONCLUSION

In this cohort of patients with highly refractory epilepsy, there was a significant association between SR, sleep disorders, and high emotional sensitivity. Careful evaluation of these factors should be performed in these patients to fully access SR.

An Overview of Psychogenic Non-Epileptic Seizures: Etiology, Diagnosis and Management

The purpose of this review is to provide an update of the research regarding the etiology, diagnosis and management of psychogenic non-epileptic seizures (PNES). A literature search using Pubmed, Ovid MEDLINE and EMBASE database was performed from 2000 up to August 2017. We have evaluated the different factors leading to PNES as well as the diagnostic approach and management of this disorder which continue to be very difficult. The coexistence of epilepsy and PNES poses special challenges and requires the coordinated efforts of the family physicians, psychiatrists, psychologists and neurologists. Although this condition has an overall poor prognosis, a multidisciplinary approach in the diagnosis and management of this disorder would likely improve the outcomes. We have proposed a diagnostic and treatment algorithm for PNES and suggested a national registry of patients suffering from this condition. The registry would contain data regarding treatment and outcomes to aid in the understanding of this entity.

[Diagnosis of non-epileptic paroxysmal disorders and epileptic seizures]

Non-epileptic paroxysmal disorders may clinically manifest in a similar way to epileptic seizures and have to be considered in the differential diagnosis of epilepsy. Syncope, non-epileptic psychogenic seizures, paroxysmal movement disorders, migraine, transient ischemic attacks and parasomnia constitute the major differential diagnoses. A meticulous history and a third party description are useful for the differential diagnosis. Neurological, psychiatric and cardiological examinations are required for the correct differential diagnosis. The interictal electroencephalogram (EEG), which is normal in non-epileptic patients, is frequently normal in epileptic patients at the onset of seizures, but reaches a high sensitivity after repeated recordings. In equivocal cases EEG video monitoring and in the case of suspected cardiac asystole, event recorders are useful diagnostic tools.

Increased odds and predictive rates of MMPI-2-RF scale elevations in patients with psychogenic non-epileptic seizures and observed sex differences

OBJECTIVE

The Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) is a self-report instrument, previously shown to differentiate patients with epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES). At present, the odds of MMPI-2-RF scale elevations in PNES patients, as well as the diagnostic predictive value of such scale elevations, remain largely unexplored. This can be of clinical utility, particularly when a diagnosis is uncertain.

METHOD

After looking at mean group differences, we applied contingency table derived odds ratios to a sample of ES (n=92) and PNES (n=77) patients from a video EEG (vEEG) monitoring unit. We also looked at the positive and negative predictive values (PPV, NPV), as well as the false discovery rate (FDR) and false omission rate (FOR) for scales found to have increased odds of elevation in PNES patients. This was completed for the overall sample, as well as the sample stratified by sex.

RESULTS

The odds of elevations related to somatic concerns, negative mood, and suicidal ideation in the PNES sample ranged from 2 to 5 times more likely. Female PNES patients had 3-6 times greater odds of such scale elevations, while male PNES patients had odds of 5-15 times more likely. PPV rates ranged from 53.66% to 84.62%, while NPV rates ranged from 47.52% to 90.91%. FDR across scales ranged from 15.38% to 50%, while the FOR ranged from 9.09% to 52.47%.

CONCLUSIONS

Consistent with prior research, PNES patients have greater odds of MMPI-2-RF scale elevations, particularly related to somatic concerns and mood disturbance. Female PNES patients endorsed greater emotional distress, including endorsement of suicide related items. Elevations of these scales could aid in differentiating PNES from ES patients, although caution is warranted due to the possibility of both false positives and the incorrect omissions of PNES cases.

MicroRNA hsa-miR-134 is a circulating biomarker for mesial temporal lobe epilepsy

Epilepsy is misdiagnosed in up to 25% of patients, leading to serious and long-lasting consequences. Recently, circulating microRNAs have emerged as potential biomarkers in a number of clinical scenarios. The purpose of this study was to identify and to validate circulating microRNAs that could be used as biomarkers in the diagnosis of epilepsy. Quantitative real-time PCR was used to measure plasma levels of three candidate microRNAs in two phases of study: an initial discovery phase with 14 patients with mesial temporal lobe epilepsy (MTLE), 13 with focal cortical dysplasia (FCD) and 16 controls; and a validation cohort constituted of an independent cohort of 65 patients with MTLE and 83 controls. We found hsa-miR-134 downregulated in patients with MTLE (p = 0.018) but not in patients with FCD, when compared to controls. Furthermore, hsa-miR-134 expression could be used to discriminate MTLE patients with an area under the curve (AUC) of 0.75. To further assess the robustness of hsa-miR-134 as a biomarker for MTLE, we studied an independent cohort of 65 patients with MTLE, 27 of whom MTLE patients were responsive to pharmacotherapy, and 38 patients were pharmacoresistant and 83 controls. We confirmed that hsa-miR-134 was significantly downregulated in the plasma of patients with MTLE when compared with controls (p < 0.001). In addition, hsa-miR-134 identified patients with MTLE regardless of their response to pharmacotherapy or the presence of MRI signs of hippocampal sclerosis. We revealed that decreased expression of hsa-miR-134 could be a potential non-invasive biomarker to support the diagnosis of patients with MTLE.

A comparative retrospective exploration of the profiles of patients in South Africa diagnosed with epileptic and psychogenic non-epileptic seizures

Psychogenic non-epileptic seizures (PNES) have a high prevalence globally but the accurate diagnosis of this condition still remains a challenge. This is particularly the case in countries where there is scarce expertise and insufficient affordable medical facilities to which patients have access. The rate of PNES diagnosis in epilepsy units is typically within the range of 20 to 30%. In the context of developing countries, this rate tends to be higher and increases demand on the existing scarce health care capacities. Although the profiling of patients with different seizure presentations is essential for informing appropriate treatment, to date there has been no comparative analysis of the profiles of patients with PNES and epilepsy in South Africa. The aim of the present study was to explore retrospectively the demographic and medication characteristics of these patients and to compare these characteristics to those reported in patient populations from other countries and regions. The total sample of 246 participants included 85 (35%) male and 161 (65%) female patients who were admitted to the Epilepsy Monitoring Unit (EMU) at Milpark Hospital, South Africa. Following the video-EEG monitoring assessment, 123 patients (50%) were diagnosed with PNES, and for 123 patients (50%) the diagnosis of epilepsy was confirmed. The results indicated that the demographic profiles of the groups of patients with epilepsy and PNES were similar with reference to age and self-ascribed ethnicity. In both groups, the majority of the patients were females, but proportionally their prevalence was higher in the PNES patient group than in the epilepsy patient group, which is compatible with the trends found in the PNES patient populations internationally. Pre-diagnostically, the type and the number of medications prescribed to patients with PNES and epilepsy were comparable. Subsequent to the diagnosis at the EMU, there was a significant reduction of overall medications in each group, but this reducton was more pronounced in the group with PNES. It is concluded that the rate of misdiagnosis of PNES in South Africa surpasses the rates reported for the patient populations in other countries and is one of the highest documented worldwide. Considering that post-diagnostically, there was reduction in central nervous system (CNS) medications as well as anti-epileptic drugs (AEDs) in both patients with epilepsy and those with PNES, it is likely that pre-diagnostically a significant proportion of all patients were over medicated. Compared to the epilepsy diagnosis, the PNES diagnosis resulted in a more substantial reduction of medication. These findings outline important dimensions of the diagnostic and medication treatment practices of epilepsy and PNES and point to the urgent need to improve these practices in South Africa and the African continent.

Paroxysmal events during prolonged video-video electroencephalography monitoring in refractory epilepsy

INTRODUCTION

Given that epileptic seizures and non-epileptic paroxysmal events have similar clinical manifestations, using specific diagnostic methods is crucial, especially in patients with drug-resistant epilepsy. Prolonged video electroencephalography monitoring during epileptic seizures reveals epileptiform discharges and has become an essential procedure for epilepsy diagnosis. The main purpose of this study is to characterise paroxysmal events and compare patterns in patients with refractory epilepsy.

METHODS

We conducted a retrospective analysis of medical records from 91 patients diagnosed with refractory epilepsy who underwent prolonged video electroencephalography monitoring during hospitalisation.

RESULTS

During prolonged video electroencephalography monitoring, 76.9% of the patients (n=70) had paroxysmal events. The mean number of events was 3.4±2.7; the duration of these events was highly variable. Most patients (80%) experienced seizures during wakefulness. The most common events were focal seizures with altered levels of consciousness, progressive bilateral generalized seizures and psychogenic non-epileptic seizures. Regarding all paroxysmal events, no differences were observed in the number or type of events by sex, in duration by sex or age at onset, or in the number of events by type of event. Psychogenic nonepileptic seizures were predominantly registered during wakefulness, lasted longer, started at older ages, and were more frequent in women.

CONCLUSIONS

Paroxysmal events recorded during prolonged video electroencephalography monitoring in patients with refractory epilepsy show similar patterns and characteristics to those reported in other latitudes.

Evaluation of MEG vs EEG after sleep deprivation in epilepsy

OBJECTIVE

MEG and EEG after sleep deprivation (EEG-SD) are applied as diagnostic tools in the evaluation of patients with possible epilepsy. There is no gold standard to check whether the diagnosis based on these two modalities is correct. The best standard available is the long-term follow-up of patients. As follow-up of an earlier study in which the additional value of MEG vs EEG-SD diagnosis was evaluated, we investigated the long-term validity of MEG-based and EEG-SD-based diagnosis.

MATERIALS AND METHODS

Data collected from 46 patients were used in a comparative study of the last known diagnosis against the original one of 8 years ago.

RESULTS

Long-term (3-8 years) sensitivity of sharp phenomena (combining spikes and sharp waves) in routine MEG and in EEG-SD for the diagnosis epilepsy is 71% and 62%, respectively. When compared to the original study, this hardly changed. Over time, uncertainty on diagnosis diminishes.

CONCLUSION

MEG as well as EEG-SD are robust long-term predictors for epilepsy.

Early childhood trauma and hippocampal volumes in patients with epileptic and psychogenic seizures

OBJECTIVE

Exposure to early life childhood trauma has been implicated as resulting in a vulnerability to epileptic and psychogenic nonepileptic seizures (PNES), hippocampal atrophy, and psychiatric disorders. This study aimed to explore the relationships between childhood trauma, epilepsy, PNES, and hippocampal volume in patients admitted to a video-electroencephalogram monitoring (VEM) unit.

METHODS

One hundred thirty-one patients were recruited from the Royal Melbourne Hospital VEM unit. The diagnostic breakdown of this group was: temporal lobe epilepsy (TLE) (32), other epilepsy syndromes (35), PNES (47), other nonepileptic syndromes (5), both epilepsy and PNES (6), and uncertain diagnosis (6). All patients completed a questionnaire assessing exposure to childhood trauma, the Childhood Trauma Questionnaire (CTQ), as well as questionnaires assessing psychiatric symptomatology (SCL-90-R), Anxiety and Depression (HADS), quality of life (QOLIE-98) and cognition (NUCOG). Volumetric coronal T1 MRI scans were available for 84 patients. Hippocampal volumes were manually traced by a blinded operator.

RESULTS

The prevalence of childhood trauma in patients with PNES was higher than in patients with other diagnoses (p=0.005), and the group with PNES overall scored significantly higher on the CTQ (p=0.002). No association was found between CTQ scores and hippocampal volumes; however, patients with a history of sexual abuse were found to have smaller left hippocampal volumes than patients who had not (p=0.043). Patients reporting having experienced childhood trauma scored lower on measures of quality of life and higher on measures of psychiatric symptomatology.

SIGNIFICANCE

Patients with PNES report having experienced significantly more childhood trauma than those with epileptic seizures, and in both groups there was a relationship between a history of having experienced sexual abuse and reduced left hippocampal volume. Patients with PNES and those with epilepsy who have a history of childhood trauma have overall worse quality of life and more psychiatric symptomatology.

Psychogenic Explanations of Physical Illness

In some patients with chronic physical complaints, detailed examination fails to reveal a well-recognized underlying disease process. In this situation, the physician may suspect a psychological cause. In this review, we critically evaluated the evidence for this causal claim, focusing on complaints presenting as neurological disorders. There were four main conclusions. First, patients with these complaints frequently exhibit psychopathology but not consistently more often than patients with a comparable “organic” diagnosis, so a causal role cannot be inferred. Second, these patients report a high incidence of adverse life experiences, but again, there is insufficient evidence to indicate a causal role for any particular type of experience. Third, although psychogenic illnesses are believed to be more responsive to psychological interventions than comparable “organic” illnesses, there is currently no evidence to support this claim. Finally, recent evidence suggests that biological and physical factors play a much greater causal role in these illnesses than previously believed. We conclude that there is currently little evidential support for psychogenic theories of illness in the neurological domain. In future research, researchers need to take a wider view concerning the etiology of these illnesses.

Peduncular psychosis

Psychotic symptoms are rarely documented in association with cortex-sparing central nervous system (CNS) lesions limited to the midbrain. We present the case of a 15-year-old boy with hereditary and environmental risk factors for psychiatric illness, as well as a history of midbrain pilocytic astrocytoma treated with chemotherapy and focused radiation, who presented with non-epileptic seizures, hyper-religiosity and frank psychosis. The space-occupying midbrain lesion has been radiographically stable while the patient has decompensated psychiatrically. Differential aetiology for the patient's psychiatric decompensation is discussed, including psychosis secondary to a lesion of the midbrain. Literature linking midbrain lesions to psychotic features, such as in peduncular hallucinosis, is briefly reviewed. This case suggests that a midbrain lesion in a susceptible patient may contribute to psychosis.

Weakened functional connectivity in patients with psychogenic non-epileptic seizures (PNES) converges on basal ganglia

BACKGROUND

Psychogenic non-epileptic seizures (PNES) are involuntary paroxysmal events that are unaccompanied by epileptiform EEG discharges. We hypothesised that PNES are a disorder of distributed brain networks resulting from their functional disconnection.The disconnection may underlie a dissociation mechanism that weakens the influence of unconsciously presented traumatising information but exerts maladaptive effects leading to episodic failures of behavioural control manifested by psychogenic 'seizures'.

METHODS

To test this hypothesis, we compared functional connectivity (FC) derived from resting state high-density EEGs of 18 patients with PNES and 18 age-matched and gender-matched controls. To this end, the EEGs were transformed into source space using the local autoregressive average inverse solution. FC was estimated with a multivariate measure of lagged synchronisation in the θ, α and β frequency bands for 66 brain sites clustered into 18 regions. A multiple comparison permutation test was applied to deduce significant between-group differences in inter-regional and intraregional FC.

RESULTS

The significant effect of PNES-a decrease in lagged FC between the basal ganglia and limbic, prefrontal, temporal, parietal and occipital regions-was found in the α band.

CONCLUSION

We believe that this finding reveals a possible neurobiological substrate of PNES, which explains both attenuation of the effect of potentially disturbing mental representations and the occurrence of PNES episodes. By improving understanding of the aetiology of this condition, our results suggest a potential refinement of diagnostic criteria and management principles.

[Conversion disorder in an internal medicine department: A series of 37 cases]

OBJECTIVES

To describe the clinical characteristics of a series of patients presenting conversion disorder in a general internal medicine ward and outpatient clinic, the arguments retained by the physicians in favour of the diagnosis, the somatic and psychiatric co-morbidities, the management and the outcome of the disorder.

METHODS

We report the study of 37 patients diagnosed with conversion disorder in an internal medicine department of a French university hospital over a period of 14 years. We retrospectively reviewed the charts of the patients and contacted their primary care physicians to obtain follow-up data. No structured instrument was used for the diagnosis of conversion disorder or for the assessment of psychiatric comorbidities.

RESULTS

As expected, patients were mostly young females, although a great variety of age, gender, and socio-cultural background was observed. Motor symptoms predominated (62%). A relevant psychogenic factor was explicitly mentioned in only 43% of the cases. In many cases, organic disease was also present, and an organic cause for the symptom initially considered as conversion was suspected in 3 cases. Depressive and anxious disorders were present respectively in 38% and 35% of cases. A pain complaint was associated in half of the cases. Among patients for whom follow-up data is available, conversion symptoms persisted or recurred in 70% of cases and were associated with a poor quality of life.

CONCLUSION

This case series confirms that the DSM-IV-TR criterion of "psychogenicity" (later abandoned in DSM-5) is highly problematic in clinical practice. It suggests a close relationship between conversion disorder and unexplained chronic pain.

Autonomic nervous system functioning associated with psychogenic nonepileptic seizures: Analysis of heart rate variability

OBJECTIVE

Psychogenic nonepileptic seizures (PNESs) resemble epileptic seizures but originate from psychogenic rather than organic causes. Patients with PNESs are often unable or unwilling to reflect on underlying emotions. To gain more insight into the internal states of patients during PNES episodes, this study explored the time course of heart rate variability (HRV) measures, which provide information about autonomic nervous system functioning and arousal.

METHODS

Heart rate variability measures were extracted from double-lead electrocardiography data collected during 1-7days of video-electroencephalography monitoring of 20 patients with PNESs, in whom a total number of 118 PNESs was recorded. Heart rate (HR) and HRV measures in time and frequency domains (standard deviation of average beat-to-beat intervals (SDANN), root mean square of successive differences (RMSSD), high-frequency (HF) power, low-frequency (LF) power, and very low-frequency (VLF) power) were averaged over consecutive five-minute intervals. Additionally, quantitative analyses of Poincaré plot parameters (SD1, SD2, and SD1/SD2 ratio) were performed.

RESULTS

In the five-minute interval before PNES, HR significantly (p<0.05) increased (d=2.5), whereas SDANN (d=-0.03) and VLF power (d=-0.05) significantly decreased. During PNES, significant increases in HF power (d=0.0006), SD1 (d=0.031), and SD2 (d=0.016) were observed. In the five-minute interval immediately following PNES, SDANN (d=0.046) and VLF power (d=0.073) significantly increased, and HR (d=-5.1) and SD1/SD2 ratio (d=-0.14) decreased, compared to the interval preceding PNES.

CONCLUSION

The results suggest that PNES episodes are preceded by increased sympathetic functioning, which is followed by an increase in parasympathetic functioning during and after PNES. Future research needs to identify the exact nature of the increased arousal that precedes PNES.