Which patients with epilepsy are at risk for psychogenic nonepileptic seizures (PNES)? A multicenter case-control study

Maladaptive personality traits in patients with epilepsy and psychogenic non-epileptic seizures

OBJECTIVE

We aimed to evaluate the sociodemographic, clinical, and psychological characteristics associated with psychogenic non-epileptic seizures (PNES) in patients with epilepsy, with particular emphasis on the personality profile assessed from a dimensional perspective.

METHODS

The cohort study included 77 consecutive inpatients with active epilepsy aged 36-55 years; 52 (67.5%) were female. The presence of PNES was confirmed by video-EEG monitoring. All patients underwent the Mini-International Neuropsychiatric Interview to diagnose psychiatric disorders. All participants completed the Neurological Disorders Depression Inventory in Epilepsy, the Epilepsy Anxiety Survey Instrument - brief version, and the Personality Inventory for DSM-5 and ICD-11 Brief Form Plus Modified. Chi-square and Fisher's exact tests were used to compare categorical variables, and the Brunner-Munzel test was used for quantitative variables.

RESULTS

Twenty-four patients (31.2%) had both epilepsy and PNES. There were no significant differences in social, demographic or clinical characteristics, psychiatric diagnoses or depression severity. Compared to patients with epilepsy alone, patients with epilepsy and PNES had higher anxiety scores and more pronounced maladaptive personality traits such as disinhibition and psychoticism.

SIGNIFICANCE

The main novelty of our study is that using the recently proposed dimensional approach to personality disorders and an appropriate instrument we assessed all personality domains listed in two of the most widely used classifications of mental disorders (DSM-5 and ICD-11) in PWE with and without PNES. To our knowledge, this is the first study to demonstrate the association of the maladaptive traits of psychoticism and disinhibition with the development of PNES in PWE.

Neuropsychological characteristics of drug resistant epilepsy patients with and without comorbid functional seizures

INTRODUCTION

Neuropsychological testing is a mandatory component in the evaluation of drug resistant epilepsy. The results of testing may assist with both the localization of an epilepsy as well as assessment of surgical risk. Previous studies have demonstrated differences in the neuropsychological performance of patients with epilepsy and functional seizures. We hypothesized that comorbid functional seizures could potentially influence neuropsychological test performance. Therefore, we evaluated whether there is a difference in the neuropsychological test results between drug resistant epilepsy patients with and without comorbid functional seizures.

METHOD

Neuropsychological test results were compared between 25 patients with drug resistant focal epilepsy and 25 patients that also had documented functional seizures. Univariate analyses and multiple logistic regression models were used to both assess performance differences between the groups and to assess whether test results could be used to accurately identify which patients had comorbid functional seizures.

RESULTS

Epilepsy patients with comorbid functional seizures performed significantly worse on the FAS Verbal Fluency Test compared to ES patients (p = 0.047). Digit Span Backwards (p = 0.10), Digit Span Forwards (p = 0.14) and Working Memory Index (p = 0.10) tended to be lower in the epilepsy and functional seizures group but was not statistically significant. A multiple logistic regression model using the results of four neuropsychological tests was able to identify patients with comorbid functional seizures with 83.33% accuracy.

CONCLUSIONS

There are appeared to be some differences in the neuropsychological performance among drug resistant epilepsy patients based on whether they have comorbid functional seizures. These findings may have relevant implications for the interpretation of neuropsychological test results.

The natural history of epilepsy and nonepileptic seizures in Sturge-Weber syndrome: A retrospective case-note review

OBJECTIVE

Patients with Sturge-Weber Syndrome (SWS) experience varying degrees of neurological problems - including epilepsy, hemiparesis, learning disability (LD), and stroke-like episodes. While the range of clinical problems experienced by children with SWS is well recognized, the spectrum of clinical presentation and its treatment during adulthood has been relatively neglected in the literature to date. This study explored the natural history of epileptic and nonepileptic seizures into adulthood in patients with SWS, and their treatment, and investigated whether any clinical factors predict which symptoms a patient will experience during adulthood.

METHODS

A retrospective case-note review of a cohort of 26 adults with SWS at the National Hospital for Neurology and Neurosurgery (NHNN). Childhood data were also recorded, where available, to enable review of change/development of symptoms over time.

RESULTS

The course of epilepsy showed some improvement in adulthood - seventeen adults continued to have seizures, while six patients gained seizure freedom, and no one had adult-onset seizures. However, seizures did worsen for some patients. Although no factors reached statistical significance regarding predicting continued epilepsy in adulthood, being male, more severe LD, having required epilepsy surgery, and bilateral cortical involvement may be important. Nonepileptic seizures (NES) also began during adulthood for four patients.

SIGNIFICANCE

By adulthood, there is some degree of improvement in epilepsy overall; while NES may occur for the first time. While the majority of the results did not survive adjustments for multiple comparisons, some interesting trends appeared, which require further investigation in a multicenter national audit. Patients with more neurologically severe presentations during childhood may continue to experience seizures. Careful monitoring and screening are needed during adulthood, to detect changes and newly developing symptoms such as NES, and target treatment promptly.

Morphometric correlates in patients with functional seizures with and without comorbid epilepsy

OBJECTIVE

Functional seizures (FS) or psychogenic, non-epileptic seizures (PNES) are episodic alterations of behaviour with similar semiology to epileptic seizures but which are not caused by epileptic brain activity. Epilepsy patients show a high risk in developing FS; therefore, the purpose of this study is to examine morphometric correlates in patients with FS as well as in epilepsy patients with FS by comparing them separately to healthy controls (HC).

METHODS

Twenty-one clinical three-dimensional (3D) T1-magnetic resonance imaging (MRI) scans of patients with FS (FS group) and 15 patients with FS and epilepsy (EFS group) were retrospectively compared with one control group of 21 age- and gender-matched HC. Two separate general linear model analyses were conducted via FreeSurfer version 6.0.

RESULTS

The study population consisted of 21 FS patients (66.7% females, n = 14) with a median age at the time of the scan of 24 years (range 17-44 years); 15 EFS patients (80% females, n = 12) with a median age at the time of the scan of 27 years (range 16-43 years); and 21 healthy subjects (66.7% females, n = 14) with a median age at the time of the scan of 24 years (range 19-38 years). Both patient groups showed an increased Cth in the right prefrontal lobe: in the FS group in the right superior frontal, rostral middle frontal gyri and the right orbitofrontal cortex and, in the EFS group, in the right superior frontal gyrus and the right orbitofrontal cortex. Decreases in Cth were present in the right lateral occipital lobe in the FS group, while also in both hemispheres in the EFS group, namely the left paracentral, superior frontal, caudal middle frontal, lateral occipital and right superior frontal gyri. Neither group showed changes in curvature.

CONCLUSION

These results suggest alterations in regions of emotional processing and executive control in patients with FS regardless of the presence of epilepsy.

Functional Neurological Disorder-Old Problem New Perspective

Functional neurological disorder (FND) is a common issue in the pediatric population. The concept and our understanding of functional neurological disorders have changed over the past years, and new etiologic models and treatment plans have been explored. Knowledge about FND in the pediatric population, however, is lacking. The aim of this review is to provide an update on pediatric functional neurological disorder. We conducted a literature search of PubMed and SCOPUS databases and reviewed a total of 85 articles to gain insight into the current understanding of FND etiology, diagnosis, treatment, and prognosis in children and adolescents. Functional and high resolution MRI revealed abnormal connectivity and structural changes in patients with functional symptoms. The diagnostic criteria no longer require the presence of a psychological factor and instead focus on a rule-in diagnosis. Treatment of FND includes a clear communication of the diagnosis and the support of a multidisciplinary team. Although FND typically has a poor prognosis, better outcomes appear to have been achieved in children and young adults. We conclude that pediatric functional neurological disorder is a prevalent pathology and that this patient population has additional specific needs compared to the adult population.

Evidence-Based Practice for the Clinical Assessment of Psychogenic Nonepileptic Seizures: A Report From the American Neuropsychiatric Association Committee on Research

The American Neuropsychiatric Association's Committee on Research assigned the task of defining the most helpful clinical factors and tests in establishing the diagnosis of psychogenic nonepileptic seizures (PNES) during a neuropsychiatric assessment. A systematic review of the literature was conducted using three search engines and specified search terms for PNES and the predetermined clinical factors and diagnostic tests, followed by a selection process with specific criteria. Data extraction results from selected articles are presented for clinical factors (semiology, psychiatric comorbidities, medical comorbidities, psychological traits) and diagnostic tests (EEG, psychometric and neuropsychological measures, prolactin level, clinical neuroimaging, autonomic testing). Semiology with video EEG (vEEG) remains the most valuable tool to determine the diagnosis of PNES. With the exception of semiology, very few studies revealed the predictive value of a clinical factor for PNES, and such findings were isolated and not replicated in most cases. Induction techniques, especially when coupled with vEEG, can lead to a captured event, which then confirms the diagnosis. In the absence of a captured event, postevent prolactin level and personality assessment can support the diagnosis but need to be carefully contextualized with other clinical factors. A comprehensive clinical assessment in patients with suspected PNES can identify several clinical factors and may include a number of tests that can support the diagnosis of PNES. This is especially relevant when the gold standard of a captured event with typical semiology on vEEG cannot be obtained.

Diagnostic accuracy of clinical signs and symptoms for psychogenic nonepileptic attacks versus epileptic seizures: A systematic review and meta-analysis

BACKGROUND

Psychogenic nonepileptic attacks (PNEA) are events of altered behavior that resemble epileptic seizures (ES) but are not caused by abnormal electrical cortical activity. Understanding which clinical signs and symptoms are associated with PNEA may allow better triaging for video-electroencephalogram monitoring (VEM) and for a more accurate prediction when such testing is unavailable.

METHODS

We performed a systematic review searching Medline, Embase, and Cochrane Central from inception to March 29, 2019. We included original research that reported at least one clinical sign or symptom, included distinct groups of adult ES and PNEA with no overlap, and used VEM for the reference standard. Two authors independently assessed quality of the studies using the Quality Assessment of Diagnostic Accuracy Studies tool. Pooled estimates of sensitivity and specificity of studies were evaluated using a bivariate random effects model.

RESULTS

We identified 4028 articles, of which 33 were included. There was a female sex predominance in the PNEA population (n = 22). From our meta-analysis, pooled sensitivities (0.27-0.72) and specificities (0.51-0.89) for PNEA were modest for individual signs. History of sexual abuse had the highest pooled specificity (89%), while the most sensitive feature was female sex (72%). Individual studies (n = 4) reported high levels of accuracy for ictal eye closure (sensitivity 64-73.7% and specificity 76.9-100%) and post-traumatic stress disorder (no reported sensitivity or specificity). Assuming the pre-test probability for PNEA in a tertiary care epilepsy center is 14%, even the strongest meta-analyzed features only exert modest diagnostic value, increasing post-test probabilities to a maximum of 33%.

CONCLUSIONS

This review reflects the limited certainty afforded by individual clinical features to distinguish between PNEA and ES. Specific demographic and comorbid features, even despite moderately high specificities, impart minimal impact on diagnostic decision making. This emphasizes the need for the development of multisource predictive tools to optimize diagnostic likelihood ratios.

Association between kinetic semiology of psychogenic nonepileptic spells and seizure type in dual disorder

PURPOSE

Epilepsy is diagnosed in 20% of patients with psychogenic nonepileptic spells (PNES). The semiology of PNES and epileptic seizures (ES) overlaps in some patients. It is unclear whether the motor phenotype of PNES predicts the type of ES.

METHODS

Video segments of EEGs in patients with PNES and ES treated in the Epilepsy Monitoring Unit at the University of Nebraska Medical Center were reviewed. Videos were categorized according to the validated motor-based classification of PNES. Ratings of kinetic PNES events were analyzed to determine if there was an association with focal or generalized ES. If available, the video segments of ES were categorized as hypokinetic or hyperkinetic based on the constellation of focal or generalized movements and other semiological features.

RESULTS

Among 43 patients with documented PNES-ES (median age 34, interquartile range (IQR) 26-45), 27.9% were male. The largest proportion of patients (39.5%) had focal temporal epilepsy (TE). Other diagnostic groups included focal frontal (FE, 25.6%), generalized (GE, 25.6%), or other (9.3%) epilepsies. Thirty-three PNES patients (82.5%) were rated as having a hypokinetic phenotype. On average, hypokinetic PNES patients were receiving a median of 3 (IQR 2-4) anticonvulsants, compared to a median of 2 (IQR 2-3) in hyperkinetic PNES patients (p = 0.06). While the group with coexisting FE had a higher prevalence of hyperkinetic semiology (45.4%) than either the TE (11.7%) or GE (18.1%) patients, there was no significant association between the ES type and kinetic status of PNES. Among 20 patients who had video recordings of both PNES and ES, 40% displayed the concordant hypokinetic phenotypes for PNES and seizures while 15% had hyperkinetic presentation of both event types. Among additional 16 patients with scalp EEG-negative suspected nonepileptic events and documented ES, 6 had the recordings of seizures and 3 have presented with concordant hypokinetic PNES and ES.

CONCLUSION

In patients with PNES and ES, the hypokinetic semiology of PNES prevails over hyperkinetic semiology in TE and GE syndromes. The motor status of PNES does not predict the phenotype of coexisting ES. The concordant kinetic semiology is present in more than half of the patients with dual diagnosis and available video data.

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).

Clinical Correlates of Functional Motor Disorders: An Italian Multicenter Study

Background

Functional motor disorders (FMDs) are abnormal movements that are significantly altered by distractive maneuvers and are incongruent with movement disorders seen in typical neurological diseases.

Objective

The objectives of this article are to (1) describe the clinical manifestations of FMDs, including nonmotor symptoms and occurrence of other functional neurological disorders (FND); and (2) to report the frequency of isolated and combined FMDs and their relationship with demographic and clinical variables.

Methods

For this multicenter, observational study, we enrolled consecutive outpatients with a definite diagnosis of FMDs attending 25 tertiary movement disorders centers in Italy. Each patient underwent a detailed clinical evaluation with a definition of the phenotype and number of FMDs (isolated, combined) and an assessment of associated neurological and psychiatric symptoms.

Results

Of 410 FMDs (71% females; mean age, 47 ± 16.1 years) the most common phenotypes were weakness and tremor. People with FMDs had higher educational levels than the general population and frequent nonmotor symptoms, especially anxiety, fatigue, and pain. Almost half of the patients with FMDs had other FNDs, such as sensory symptoms, nonepileptic seizures, and visual symptoms. Patients with combined FMDs showed a higher burden of nonmotor symptoms and more frequent FNDs. Multivariate regression analysis showed that a diagnosis of combined FMDs was more likely to be delivered by a movement disorders neurologist. Also, FMD duration, pain, insomnia, diagnosis of somatoform disease, and treatment with antipsychotics were all significantly associated with combined FMDs.

Conclusions

Our findings highlight the need for multidimensional assessments in patients with FMDs given the high frequency of nonmotor symptoms and other FNDs, especially in patients with combined FMDs.

[The problem of comorbidity of epilepsy and psychogenic paroxysms]

A review of publications over the last two decades is presented. Psychogenic paroxysms develop in approximately 12% of patients with epilepsy. The analysis of social and demographic data, history details, semiological features and results of electrophysiological and neuroimaging studies does not unequivocally support the comorbidity of epilepsy and psychogenic paroxysms. The pathogenetic mechanisms of the development of comorbidity are various and depend on the presence of pharmacoresistance, psychological traumas in the past, intellectual disability etc. Video-EEG-monitoring is the gold standard in the diagnosis of comorbidity of epilepsy and psychogenic paroxysms. Treatment of such cases includes anticonvulsants and cognitive-behavioral therapy.

International multicenter studies on psychogenic nonepileptic seizures: A systematic review

The aim of the current paper is to systematically review the literature on the existing international multicenter studies on various aspects of PNES and to highlight their findings and significance. I searched the electronic database PubMed for articles that included any of these search terms: Non-epileptic seizures, Nonepileptic seizures, Pseudoseizures, Non-epileptic events, Nonepileptic events, Dissociative seizures, Psychogenic, PNES, AND "international" or "multicenter" or "cross cultural", in their abstracts and titles and published before August 6, 2019. I searched PsycINFO database (keywords in the abstracts) and also included some of the references of the selected articles if they were relevant. I could identify 12 related manuscripts through the search strategy. These included seven studies on patients with PNES, two surveys, and three consensus group reports. This systematic review showed that international and cross-cultural studies on PNES to date are very limited in number and quality. However, these limited studies have resulted in intriguing observations and conclusions. International and cross-cultural studies may make important contributions to our understanding of different aspects of PNES across borders.

Differential diagnosis between epileptic seizures and psychogenic nonepileptic seizures based on semiology

Psychogenic nonepileptic seizures present as paroxysmal symptoms and signs mimicking epileptic seizures. The gold standard test is the synchronous recording by video, electrocardiogram and electroencephalogram. However, video electroencephalogram is not available at many centers and not entirely independent of semiology. Recent studies have focused on semiological characteristics distinguishing these two circumstances. Clinical signs and symptoms provide important clues when making differential diagnosis. The purpose of this review is to help physicians differentiating psychogenic nonepileptic seizures better from epileptic seizures based on semiology, and improve care for those patients.

Current Concepts in Diagnosis and Treatment of Functional Neurological Disorders

Importance

Functional neurological disorders (FND) are common sources of disability in medicine. Patients have often been misdiagnosed, correctly diagnosed after lengthy delays, and/or subjected to poorly delivered diagnoses that prevent diagnostic understanding and lead to inappropriate treatments, iatrogenic harm, unnecessary and costly evaluations, and poor outcomes.

Observations

Functional Neurological Symptom Disorder/Conversion Disorder was adopted by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, replacing the term psychogenic with functional and removing the criterion of psychological stress as a prerequisite for FND. A diagnosis can now be made in an inclusionary manner by identifying neurological signs that are specific to FNDs without reliance on presence or absence of psychological stressors or suggestive historical clues. The new model highlights a wider range of past sensitizing events, such as physical trauma, medical illness, or physiological/psychophysiological events. In this model, strong ideas and expectations about these events correlate with abnormal predictions of sensory data and body-focused attention. Neurobiological abnormalities include hypoactivation of the supplementary motor area and relative disconnection with areas that select or inhibit movements and are associated with a sense of agency. Promising evidence has accumulated for the benefit of specific physical rehabilitation and psychological interventions alone or in combination, but clinical trial evidence remains limited.

Conclusions and Relevance

Functional neurological disorders are a neglected but potentially reversible source of disability. Further research is needed to determine the dose and duration of various interventions, the value of combination treatments and multidisciplinary therapy, and the therapeutic modality best suited for each patient.

Morbidity and mortality of nonepileptic seizures (NES): A controlled national study

Nonepileptic seizures (NES, psychogenic NES-PNES) are associated with significant morbidities. We evaluated the morbidities and mortality in a national group of children, adolescent, and adult patients before and after a first diagnosis of PNES.

METHODS

From the Danish National Patient Registry (1998-2013), we identified 1057 people of all ages with a diagnosis of NES and matched them with 2113 control individuals by age, gender, and geography. Comorbidities were calculated three years before and after diagnoses.

RESULTS

Patients with PNES showed increased comorbidities 3 years before and after diagnosis in almost all the diagnostic domains. The strongest associations were identified with other neurological diseases (after diagnosis, Hazard Ratio (HR): 38.63; 95% Confidence Interval (CI): 21.58-69.13; P < 0.001), abnormal clinical and laboratory findings (HR: 46.59; 95 CI: 27.30-79.52; P < 0.001), other health-related factors (HR: 12.83; 95%CI: 8.45-19.46; P < 0.001), and psychiatric comorbidities (HR: 15.45; 95% CI: 9.81-24.33). Epilepsy was identified in 8% of the patients with PNES. We found especially frequent comorbidity involving overweight, depression, anxiety, dissociative somatoform condition, other convulsions, lipothymias, reports of pain and other symptoms in several organ systems, and several reports of minimal traumas to the head, trunk, and extremities. Mortality was higher in patients with NES than in controls (HR: 3.21; 95% CI: 1.92-5.34; P < 0.001).

CONCLUSION

Morbidity is more frequent in several domains, including neurological, psychiatric, and other diseases, before and after a diagnosis of NES. Mortality is significantly higher in patients with PNES as compared to controls.

Dual diagnosis of epilepsy and psychogenic nonepileptic seizures: Systematic review and meta-analysis of frequency, correlates, and outcomes

Comorbid epilepsy and psychogenic nonepileptic seizures (PNES) represent a serious challenge for the clinicians. However, the frequency, associations, and outcomes of dual diagnosis of epilepsy and PNES are unclear. The aim of the review was to determine the frequency, correlates, and outcomes of a dual diagnosis. A systematic review of all published observational studies (from inception to Dec. 2016) was conducted to determine the frequency, correlates, and outcomes of dual diagnosis. We included studies of individuals of any age reporting a dual diagnosis of epilepsy and PNES. All observational study designs were included with the exception of case reports and case series with fewer than 10 participants. The mean frequency of epilepsy in patients with PNES across all studies was 22% (95% confidence intervals [CI] 20 to 25%, range: 0% to 90%) while the mean frequency of PNES in patients with epilepsy was 12% (95% CI 10 to 14%, range: 1% to 62%). High heterogeneity means that these pooled estimates should be viewed with caution. A number of correlates of dual diagnosis were reported. Some studies delineated differences in semiology of seizures in patients with dual diagnosis vs. PNES or epilepsy only. However, most of the correlates were inconclusive. Only a few studies examined outcome in patients with dual diagnosis. Dual diagnosis is common in clinical practice, especially among patients referred to specialized services, and requires careful diagnosis and management.

Neuropsychiatric features of the coexistence of epilepsy and psychogenic nonepileptic seizures

OBJECTIVE

To investigate demographic, epidemiologic and psychiatric features suggestive of the coexistence epilepsy (ES) and psychogenic nonepileptic seizures (PNES) that may contribute to precocious suspicion of the association.

METHODS

In this exploratory study, all patients older than 16 years admitted to prolonged video-electroencephalogram monitoring were evaluated about demographic, epileptological and psychiatric features. Detailed psychiatric assessment using M.I.N.I.-plus 5.0, Beck Anxiety Inventory, Beck Depression Inventory and the Childhood Trauma Questionnaire (CTQ) was performed. Data were collected previous to the final diagnosis and patients with ES-only, PNES-only or coexistence of ES/PNES were compared.

RESULTS

Of 122 patients admitted to epilepsy monitoring unit, 86 patients were included and 25 (29%) had PNES. Twelve (14%) had PNES-only, 13 (15%) had ES/PNES and the remaining 61 (71%) had only ES. A coexistence of ES and PNES was associated with clinical report of more than one seizure type (p˂0.001), nonspecific white matter hyperintensities on MRI (p < .001) and a past of psychotic disorder (p = .005). In addition, these patients had significantly more emotional abuse and neglect (p < .002 and 0.001, respectively). Somatization (including conversion disorder) was the most common diagnosis in patients with PNES- only (83%) and co-existing of PNES and ES (69.2%), differentiating both from ES-only patients (p < .001).

CONCLUSION

The high prevalence of this coexistence ES/PNES in this study reinforces a need to properly investigate PNES, especially in patients with confirmed ES who become refractory to medical treatment with antiepileptic drugs. The neuropsychiatric assessment may help to diagnostic suspicion and in the planning of therapeutic interventions.

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.

Functional neurological disorders in Parkinson disease

OBJECTIVE

To ascertain demographic and clinical features of Parkinson disease (PD) associated with functional neurological features.

METHODS

A standardised form was used to extract data from electronic records of 53 PD patients with associated functional neurological disorders (PD-FND) across eight movement disorders centres in the USA, Canada and Europe. These subjects were matched for age, gender and disease duration to PD patients without functional features (PD-only). Logistic regression analysis was used to compare both groups after adjusting for clustering effect.

RESULTS

Functional symptoms preceded or co-occurred with PD onset in 34% of cases, nearly always in the most affected body side. Compared with PD-only subjects, PD-FND were predominantly female (68%), had longer delay to PD diagnosis, greater prevalence of dyskinesia (42% vs 18%; P=0.023), worse depression and anxiety (P=0.033 and 0.025, respectively), higher levodopa-equivalent daily dose (972±701 vs 741±559 mg; P=0.029) and lower motor severity (P=0.019). These patients also exhibited greater healthcare resource utilisation, higher use of [(123)I]FP-CIT SPECT and were more likely to have had a pre-existing psychiatric disorder (P=0.008) and family history of PD (P=0.036).

CONCLUSIONS

A subtype of PD with functional neurological features is familial in one-fourth of cases and associated with more psychiatric than motor disability and greater use of diagnostic and healthcare resources than those without functional features. Functional manifestations may be prodromal to PD in one-third of patients.

Facial emotion processing in patients with seizure disorders

Studies of emotion processing are needed to better understand the pathophysiology of psychogenic nonepileptic seizures (PNES). We examined the differences in facial emotion processing between 12 patients with PNES, 12 patients with temporal lobe epilepsy (TLE), and 24 matched healthy controls (HCs) using fMRI with emotional faces task (EFT) (happy/sad/fearful/neutral) and resting state connectivity. Compared with TLE, patients with PNES exhibited increased fMRI response to happy, neutral, and fearful faces in visual, temporal, and/or parietal regions and decreased fMRI response to sad faces in the putamen bilaterally. Regions showing significant differences between PNES and TLE were used as functional seed regions of interest (ROIs), in addition to amygdala structural seed ROIs for resting state functional connectivity analyses. Whole brain analyses showed that compared with TLE and HCs, patients with PNES exhibited increased functional connectivity of the functional seed ROIs to several brain regions, particularly to cerebellar, visual, motor, and frontotemporal regions. Connectograms showed increased functional connections between left parahippocampal gyrus/uncus ROIs and right temporal ROIs in PNES compared with both the TLE and HC groups. Resting state functional connectivity of the left and right amygdala to various brain regions including emotion regulation and motor control circuits was increased in PNES when compared with those with TLE. This study provides preliminary evidence that patients with PNES exhibit altered facial emotion processing compared with patients with TLE and HCs and increased amygdala functional connectivity compared with TLE. These findings identify potential key differences in facial emotion processing reflective of neurophysiologic markers of neural circuitry alterations that can be used to generate further hypotheses for developing studies that examine the contributions of emotion processing to the development and maintenance of PNES.

Low-to-High Cross-Frequency Coupling in the Electrical Rhythms as Biomarker for Hyperexcitable Neuroglial Networks of the Brain

OBJECTIVE

One of the features used in the study of hyperexcitablility is high-frequency oscillations (HFOs, >80 Hz). HFOs have been reported in the electrical rhythms of the brain's neuroglial networks under physiological and pathological conditions. Cross-frequency coupling (CFC) of HFOs with low-frequency rhythms was used to identify pathologic HFOs in the epileptogenic zones of epileptic patients and as a biomarker for the severity of seizure-like events in genetically modified rodent models. We describe a model to replicate reported CFC features extracted from recorded local field potentials (LFPs) representing network properties.

METHODS

This study deals with a four-unit neuroglial cellular network model where each unit incorporates pyramidal cells, interneurons, and astrocytes. Three different pathways of hyperexcitability generation-Na - ATPase pump, glial potassium clearance, and potassium afterhyperpolarization channel-were used to generate LFPs. Changes in excitability, average spontaneous electrical discharge (SED) duration, and CFC were then measured and analyzed.

RESULTS

Each parameter caused an increase in network excitability and the consequent lengthening of the SED duration. Short SEDs showed CFC between HFOs and theta oscillations (4-8 Hz), but in longer SEDs the low frequency changed to the delta range (1-4 Hz).

CONCLUSION

Longer duration SEDs exhibit CFC features similar to those reported by our team.

SIGNIFICANCE

First, Identifying the exponential relationship between network excitability and SED durations; second, highlighting the importance of glia in hyperexcitability (as they relate to extracellular potassium); and third, elucidation of the biophysical basis for CFC coupling features.

Psychiatric and behavioral comorbidities in epilepsy: A critical reappraisal

Psychiatric and behavioral disorders are important aspects of epilepsy and have received increasing attention in the last several years. The literature upon which most of the field relies contains some biases that must be carefully examined and resolved in future studies. First, in the pediatric epilepsy literature, many reports find that children with epilepsy have high levels of behavioral and psychiatric disorders when compared to appropriate controls. Most of these studies rely on parent-proxy completed instruments to assess these behavioral endpoints. Parents' reports are not objective but reflect parents' reactions and emotions. Increasing evidence suggests inherent biases in proxy reports and highlights the need to assess children directly. Second, periictal phenomena may be mischaracterized as underlying mood disorders. Third, many studies report elevated levels of psychiatric morbidity before and after the diagnosis of epilepsy, suggesting an inherent relation between the two types of disorders. Psychogenic nonepileptic seizures, while widely recognized as posing a diagnostic dilemma in the clinic, may account for some of these research findings. Diagnostic errors between epilepsy and psychogenic nonepileptic seizures need careful consideration when evaluating studies demonstrating associations between psychiatric disorders and epilepsy or poorer seizure control in association with psychiatric disorders in people who have epilepsy. Mental health concerns are important for everyone. An accurate, undistorted understanding of the relation between mental health disorders and epilepsy is essential to ensure appropriate therapy and to avoid unnecessary and potentially harmful treatments and common misconceptions.

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.