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.

Breathing control training for functional seizures: A multi-site, open-label pilot study

There are no well-validated treatments for functional seizures. While specialist psychotherapy is usually recommended, the evidence for its benefit is qualified, and it can be difficult to obtain. Given the association between hyperventilation and functional seizures we explored an alternative modality, breathing control training, in a multi-site open label pilot trial. Participants with functional seizures over the age of 16 received an hour of breathing training from a respiratory physiotherapist, with a half-hour booster session a month later. Seizure frequency and Nijmegen scores (a measure of hyperventilation) were reported at baseline and follow-up, 3-4 months later. Eighteen subjects were recruited, and 10 completed follow-up. Seven of these 10 had improved seizure frequency, and 3 did not (Wilcoxon signed rank test, p = 0.09), with seizure frequency correlating with Nijmegen score (Spearman's rank correlation = 0.75, p = 0.034). The intervention was well tolerated, with no adverse events reported. These preliminary results support a potentially new approach to treating functional seizures that should prove cost-effective and acceptable, though require confirmation by a randomised controlled trial.

Experimental assessment of seizure-like behaviors in a girl with Rett syndrome

Contextual events are recognized to affect seizure-like behaviors, yet there is limited research on procedures assessing contextual control. This study aimed to examine the utilization of a brief experimental precursor functional analysis within a clinical team assessment. Furthermore, the study explored if telehealth supervision could guide a parent administered replication of the functional analysis. The participants were a young female with Rett syndrome and a history of epilepsy as well as non-epileptic seizures and her mother. The functional analysis procedures consisted of the systematic alternations of contextual conditions that were hypothesized to either prevent or evoke seizure-like behaviors. The primary outcome measure was the occurrence of behavioral precursors that were identified to consequently signal subsequent seizure-like behaviors. In addition, procedure fidelity and interobserver agreement data were obtained alongside parent rating of the procedure's social validity. The clinical functional analysis clearly suggested that the seizure-like behaviors served the function of access to attention and preferred activities. A parent administered functional analysis replicated clinical functional analysis findings. The parent's fidelity to procedures was high and scores in social validity were excellent. The results show that functional analysis procedures could provide essential information in assessment of non-epileptic seizures. Strengths and limitations are discussed.

Testing the diagnostic accuracy of common questions for seizure diagnosis: Challenges and future directions

OBJECTIVE

The aim of this study was to evaluate the diagnostic accuracy of common interview questions used to distinguish a diagnosis of epilepsy from seizure mimics including non-epileptic seizures (NES), migraine, and syncope.

METHODS

200 outpatients were recruited with an established diagnosis of focal epilepsy (n = 50), NES (n = 50), migraine (n = 50), and syncope (n = 50). Patients completed an eight-item, yes-or-no online questionnaire about symptoms related to their events. Sensitivity and specificity were calculated. Using a weighted scoring for the questions alone with baseline characteristics, the overall questionnaire was tested for diagnostic accuracy.

RESULTS

Of individual questions, the most sensitive one asked if events are sudden in onset (98 % sensitive for epilepsy (95 % CI: 89 %, 100 %)). The least sensitive question asked if events are stereotyped (46 % sensitive for epilepsy (95 % CI: 32 %, 60 %)). Overall, three of the eight questions showed an association with epilepsy as opposed to mimics. These included questions about "sudden onset" (OR 10.76, 95 % CI: (1.66, 449.21) p = 0.0047), "duration < 5 min" (OR 3.34, 95 % CI: (1.62, 6.89), p = 0.0008), and "duration not > 30 min" (OR 4.44, 95 % CI: (1.94, 11.05), p = <0.0001). When individual seizure mimics were compared to epilepsy, differences in responses were most notable between the epilepsy and migraine patients. Syncope and NES were most similar in responses to epilepsy. The overall weighted questionnaire incorporating patient age and sex produced an area under the ROC curve of 0.80 (95 % CI: 0.74, 0.87)).

CONCLUSION

In this study, we examined the ability of common interview questions used by physicians to distinguish between epilepsy and prevalent epilepsy mimics, specifically NES, migraines, and syncope. Using a weighted scoring system for questions, and including age and sex, produced a sensitive and specific predictive model for the diagnosis of epilepsy. In contrast to many prior studies which evaluated either a large number of questions or used methods with difficult practical application, our study is unique in that we tested a small number of easy-to-understand "yes" or "no" questions that can be implemented in most clinical settings by non-specialists.

Routine outcomes and evaluation of an 8-week outpatient multidisciplinary rehabilitative therapy program for functional neurological disorder

OBJECTIVES

We report routinely collected outcome data from an 8-week outpatient rehabilitative therapy program. The aims of the intervention were to (1) reduce symptom severity and (2) improve functional mobility in adults with functional neurological disorder (FND).

METHODS

The program delivered individual physiotherapy, cognitive behavioral therapy (CBT) and self-management sessions, group physiotherapy, and psychoeducation. Outcome measures included the Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI-II), Work and Social Adjustment Scale (WSAS), 10-Meter Walk Test (10MWT), Timed Up and Go (TUG), and Berg Balance Scale (BBS). Data were analyzed retrospectively in accordance with routine service evaluation. Wilcoxon signed-rank tests assessed changes in outcomes between weeks 1 and 8 for all patients completing treatment (n = 45). For patients who attended the 3-month follow-up (n = 31), Friedman's ANOVA assessed overall change in outcomes over time. Post hoc Wilcoxon signed-rank tests compared pairs of time-points (Weeks 1, 8, and 3-month follow-up).

RESULTS

Analyses of patients completing the program revealed significant improvements in scores between week 1 and week 8. Excluding the BBS, there were statistically significant improvements in all outcomes between weeks 1 and 8 and between weeks 1 and 3-month follow-up.

DISCUSSION

This outpatient therapy program provided effective treatment for FND. Patients reported reduced anxiety, depression, and functional impairment, as well as improved performance on most physiotherapy measures.

Nocebo Hypothesis Cognitive Behavioural Therapy (NH-CBT) for non-epileptic seizures: a consecutive case series

BACKGROUND

Research has demonstrated that implementation of Nocebo Hypothesis Cognitive Behavioural Therapy (NH-CBT) achieved full symptom remission in 93% of people with Functional Neurological Symptoms Disorder (FNSD), most of them exhibiting motor symptoms. The basis for NH-CBT is consistent with a predictive coding aetiological model of FNSD. This idea is transparently shared with people with FNSD in the form of telling them that their symptoms are caused by a nocebo effect, usually followed by some physical activity that aims to change the person's belief about their body.

AIMS

To demonstrate that a version of NH-CBT can also be effective in eliminating or reducing non-epileptic seizures (assumed to be a sub-type of FNSD).

METHOD

A consecutive case series design was employed. Participants were treated with NH-CBT over a 12-week period. The primary outcome measure was seizure frequency. Numerous secondary measures were employed, as well as a brief qualitative interview to explore participants' subjective experience of treatment.

RESULTS

Seven out of the 10 participants became seizure free at least 2 weeks before their post-treatment assessment, and all stayed seizure-free for at least 5 months. Six of those seven remained seizure free at 6-month follow-up. There were large positive effect sizes for the majority of secondary measures assessed.

CONCLUSIONS

This case series provides evidence of feasibility and likely utility of NH-CBT in reducing the frequency of non-epileptic seizures.

Setting up Functional Neurological Disorder Treatment Services: Questions and Answers

Functional neurologic disorder (FND) is commonly encountered across outpatient and inpatient medical settings. Given the potential for a high burden of disability in some patients and mounting evidence for the efficacy of FND-specific multidisciplinary treatment services, expanding clinical services for this population is a necessity. In this perspective article, we discuss considerations for creating FND services, including the types of services that exist, how to start, how to identify appropriate referrals, and how to develop and monitor individualized treatment plans. In addition, we discuss how this effort can be done sustainably - balancing patient needs with limited healthcare resources.

Interoception in functional motor symptoms and functional seizures: Preliminary evidence of intact accuracy alongside reduced insight and altered sensibility

Altered interoception may be a pathophysiological mechanism in functional neurological disorder (FND). However, findings have been inconsistent across interoceptive dimensions in FND including functional motor symptoms (FMS) and seizures (FS). Here, individuals with FMS/FS (n = 17) and healthy controls (HC, n = 17) completed measures of interoceptive accuracy and insight (adapted heartbeat tracking task [HTT] with confidence ratings), a time estimation control task (TET) and the Multidimensional Assessment of Interoceptive Awareness-2 (MAIA-2) to assess interoceptive sensibility. The groups did not differ in interoceptive accuracy (p = 1.00, g = 0.00) or confidence (p = .99, g = 0.004), although the FMS/FS group displayed lower scores on the "Not-Distracting" (p < .001, g = 1.42) and "Trusting" (p = .005, g = 1.17) MAIA-2 subscales, relative to HCs. The groups did not differ in TET performance (p = .82, g = 0.08). There was a positive relationship between HTT accuracy and confidence (insight) in HCs (r = .61, p = .016) but not in FMS/FS (r = 0.11, p = .69). HTT confidence was positively correlated with MAIA-2 "Self-Regulation" (r = 0.77, p = .002) and negatively correlated with FND symptom severity (r = -0.84, p < .001) and impact (r = -0.86, p < .001) in FMS/FS. Impaired interoceptive accuracy may not be a core feature in FMS/FS, but reduced insight and altered sensibility may be relevant. Reduced certainty in self-evaluations of bodily experiences may contribute to the pathogenesis of FND symptoms.

Rates of event capture of home video EEG

OBJECTIVE

Recording electrographic and behavioral information during epileptic and other paroxysmal events is important during video electroencephalography (EEG) monitoring. This study was undertaken to measure the event capture rate of an home service operating across Australia using a shoulder-worn EEG device and telescopic pole-mounted camera.

METHODS

Neurologist reports were accessed retrospectively. Studies with confirmed events were identified and assessed for event capture by recording modality, whether events were reported or discovered, and physiological state.

RESULTS

6,265 studies were identified, of which 2,788 (44.50%) had events. A total of 15,691 events were captured, of which 77.89% were reported. The EEG amplifier was active for 99.83% of events. The patient was in view of the camera for 94.90% of events. 84.89% of studies had all events on camera, and 2.65% had zero events on camera (mean = 93.66%, median = 100.00%). 84.42% of events from wakefulness were reported, compared to 54.27% from sleep.

CONCLUSIONS

Event capture was similar to previously reported rates from home studies, with higher capture rates on video. Most patients have all events captured on camera.

SIGNIFICANCE

Home monitoring is capable of high rates of event capture, and the use of wide-angle cameras allows for all events to be captured in the majority of studies.

Improved understanding of non-epileptic seizures and reduced emergency health care usage following a single psychoeducational group for children and their parents

RATIONALE

The aim of this study was to evaluate the effectiveness of a three-hour psychoeducation group in improving understanding of non-epileptic seizures (NES), health outcomes and quality of life in young people with NES.

BACKGROUND

Multi-session psychoeducational groups for adults with NES have reported improved psychosocial functioning and reduced NES compared to those who do not receive psychoeducational interventions. To date there have been no studies in young people examining the effects of a single session of psychoeducation.

METHOD

15 young people with NES and their families attended a psychoeducation group within a specialist hospital following a multidisciplinary assessment. The group's effectiveness was evaluated in terms of perceptions of seizure controllability, seizure severity, the management of the condition and health-related quality of life measures.

RESULTS

A significant decrease in accident and emergency (A&E) visits and ambulance call outs was observed following the psychoeducation group. Young people additionally reported increased knowledge of NES and ability to cope with the condition which was maintained at 6-week follow-up. Significant reduction in NES occurrence or quality of life was not observed.

CONCLUSION

Significant reduction in A&E attendance and ambulance use was found following group psychoeducation and improvements in psychosocial functioning and knowledge about NES. Group psychoeducation has the potential to increase child and parental understanding of NES and reduce inappropriate healthcare usage.

A clinician's perspective in the management of functional seizures

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Treatment of Functional seizures begins with therapeutic interventions guided by CBT.

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Treatment begins with change through behavioral interventions, as well as cognitive talk therapy.

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Systemic issues and co occurring mental health concerns are also addressed.

Patients struggling with functional seizures represent a significant issue for institutions across the country. Fortunately, they often respond to regular Cognitive Behavioral oriented psychotherapy. This patient population tends to be underserved, and it is the hope that my experience in their treatment will alleviate this problem. My approach to therapy is largely self taught, and based on observation, trial and error, and over ten years of experience. My approach begins with the introduction of behavioural interventions, and as treatment progresses, I begin to rely on talk therapy aimed at the introduction of cognitive interventions. Treatment begins with an analysis of their episodes followed by interventions aimed at symptom reduction. Longer term goals include the management of co occurring mental health concerns and systemic issues.

How to do things with words Two seminars on the naming of functional (psychogenic, non-epileptic, dissociative, conversion, …) seizures

Amongst the most important conditions in the differential diagnosis of epilepsy is the one that manifests as paroxysms of altered behaviour, awareness, sensation or sense of bodily control in ways that often resemble epileptic seizures, but without the abnormal excessive or synchronous electrical activity in the brain that defines these. Despite this importance, there remains little agreement - and frequent debate - on what to call this condition, known inter alia as psychogenic non-epileptic seizures (PNES), dissociative seizures (DS), functional seizures (FS), non-epileptic attack disorder (NEAD), pseudoseizures, conversion disorder with seizures, and by many other labels besides. This choice of terminology is not merely academic - it affects patients' response to and understanding of their diagnosis, and their ability to navigate health care systems.This paper summarises two recent discussions hosted by the American Epilepsy Society and Functional Neurological Disorders Society on the naming of this condition. These discussions are conceptualised as the initial step of an exploration of whether it might be possible to build consensus for a new diagnostic label.

[Young patient with recurrent unexplained syncope]

A young woman with recurrent syncope, which remained unexplained despite multiple cardiologic and neurologic investigations, presented for invasive cardiologic work-up including the implantation of a loop recorder. The diagnosis could be established merely by taking the patient's medical history; further investigations were limited to tilt table testing just to confirm the diagnosis.

Demographic and clinical phenotypic differences between people with dissociative seizures and those with other psychiatric disorders

BACKGROUND

A large amount of literature surrounds the differences between dissociative neurological symptom disorder with non-epileptic seizures (DNSD-S) and epilepsy.

AIMS

To explore the research gap on phenotypic differences between DNSD-S and other psychiatric disorders.

METHOD

We conducted a case-control study of 1860 patients (620 patients with DNSD-S and 1240 controls with other psychiatric disorders) seen at the South London and Maudsley Hospital NHS Trust between 2007 and 2019.

RESULTS

Compared with the controls, the patients with DNSD-S were more likely to be female (76 v. 47%, P < 0.001), of White ethnicity (77 v. 60%, P < 0.001), married (34 v. 14%, P < 0.001) and living in areas of lower socioeconomic status (-3.79, 95% CI -2.62 to -4.96, P < 0.001). Two peaks for age at diagnosis were observed for DNSD-S: the early 20s and late 40s. After 31 years of age, men's chance of being diagnosed with DNSD-S increased from 19 to 28% (P = 0.009). People with DNSD-S presented more commonly with a history of a neurological episodic or paroxysmal disorder (OR = 12, 95% CI 7.82-20.26), another dissociative disorder (OR = 10, 95% CI 1.64- 65.95) or unclassified signs or symptoms (OR = 4, 95% CI 2.61-6.43). Neither anxiety, depression nor other somatoform disorders predicted subsequent diagnosis of DNSD-S, and controls had a larger proportion of preceding psychiatric diagnoses than patients with DNSD-S (65 v. 49%, P < 0.001).

CONCLUSIONS

This is the first study comparing demographic and phenotypic correlates of patients with DNSD-S against a large cohort of psychiatric patients. These data will inform development and drive service needs in psychiatry for people with DNSD-S.

Sex Effects on Coping, Dissociation, and PTSD in Patients With Non-epileptic Seizures

PURPOSE OF REVIEW

Sex differences in non-epileptic seizures (NES) are of interest, as the diagnosis is more frequent in women than men (3:1 ratio). This paper reviews clinical findings regarding sex differences in NES through selective literature review and compares coping measures between women and men in our NES clinic.

RECENT FINDINGS

Some distinguishing clinical features of NES in women and men are reported in the literature. However, we found few sex differences in demographics and coping. In our population, avoidance and dissociation were strongly related to one another and significantly related to co-occurring PTSD diagnosis, which was seen in over 50% in both sexes. Our findings confirm a high prevalence of PTSD in patients with NES, suggesting that comorbid PTSD may override sex differences in accounting for use of avoidant and dissociative coping. These findings raise the possibility that NES may, at times, represent an extreme variant in dysfunctional coping in patients with PTSD.

Blood CRP levels are elevated in children and adolescents with functional neurological symptom disorder

There is accumulating evidence that patients with functional neurological symptom disorder (FND) show activation of multiple components of the stress system-the hypothalamic-pituitary-adrenal axis, autonomic nervous system, and brain regions involved in arousal- and emotion-processing. This study aims to examine whether the immune-inflammatory component of the stress system is also activated. C-reactive protein (CRP) blood titre levels were measured in 79 children and adolescents with FND. CRP values ≥ 2 mg/L suggest low-grade inflammation. CRP values > 10 mg/L suggest a disease process. Sixty-six percent of subjects (n = 52) had CRP titres ≥ 2 mg/L. The upward shift in the distribution of CRP levels suggested low-grade inflammation (median CRP concentration was 4.60 mg/L, with 75th and 90th percentiles of 6.1 and 10.3 mg/L, respectively). Elevated CRP titres were not explained by sex, pubertal status, BMI, or medical factors. Confounder analyses suggested that history of maltreatment (χ² = 2.802, df = 1, p = 0.094, φ = 0.190; β = 2.823, p = 0.04) and a diagnosis of anxiety (χ² = 2.731, df = 1, p = 0.098, φ = 0.187; β = 4.520, p = 0.061) contributed to elevated CRP levels. Future research will need to identify the origins and locations of immune cell activation and the pathways and systems contributing to their activation and modulation. Because functional activity in neurons and glial cells-the brain's innate effector immune cells-is tightly coupled, our finding of elevated CRP titres suggests activation of the immune-inflammatory component of the brain's stress system. A more direct examination of inflammation-related molecules in the brain will help clarify the role of immune-inflammatory processes in FND.

Cerebellar fits in the 2000s

Acute compression on the brainstem or acute increase in intracranial pressure may induce non-epileptic events varying from tonic seizures to axial rigidity with motor automatism, sometimes clearly characterized by decerebrate or decorticate paroxysmal posturing. The EEG correlate is characterized by diffuse asynchronous slow waves of variable amplitude. The mechanism behind such events, known as "cerebellar seizures or fits", is linked to cerebellar herniation and brainstem compression and is not of cortical origin. Misrecognition of such entity may entail an incongruous therapeutic intervention in a life-threatening situation. We describe two emblematic paediatric cases of cerebellar fits caused by diffuse oedema and brainstem compression: a 10-year-old girl with acute disseminated encephalomyelitis (ADEM) and a 2-year-old girl with severe respiratory distress symptomatic of Fallot tetralogy. We also describe the EEG correlate recorded during the events.

COgnitive behavioural therapy versus standardised medical care for adults with Dissociative non-Epileptic Seizures (CODES): statistical and economic analysis plan for a randomised controlled trial

Background

Dissociative seizures (DSs), also called psychogenic non-epileptic seizures, are a distressing and disabling problem for many patients in neurological settings with high and often unnecessary economic costs. The COgnitive behavioural therapy versus standardised medical care for adults with Dissociative non-Epileptic Seizures (CODES) trial is an evaluation of a specifically tailored psychological intervention with the aims of reducing seizure frequency and severity and improving psychological well-being in adults with DS. The aim of this paper is to report in detail the quantitative and economic analysis plan for the CODES trial, as agreed by the trial steering committee.

Methods

The CODES trial is a multicentre, pragmatic, parallel group, randomised controlled trial performed to evaluate the clinical effectiveness and cost-effectiveness of 13 sessions of cognitive behavioural therapy (CBT) plus standardised medical care (SMC) compared with SMC alone for adult outpatients with DS.

Discussion

The objectives and design of the trial are summarised, and the aims and procedures of the planned analyses are illustrated. The proposed analysis plan addresses statistical considerations such as maintaining blinding, monitoring adherence with the protocol, describing aspects of treatment and dealing with missing data. The formal analysis approach for the primary and secondary outcomes is described, as are the descriptive statistics that will be reported. This paper provides transparency to the planned inferential analyses for the CODES trial prior to the extraction of outcome data. It also provides an update to the previously published trial protocol and guidance to those conducting similar trials.

Trial registration

ISRCTN registry ISRCTN05681227 (registered on 5 March 2014); ClinicalTrials.gov NCT02325544 (registered on 15 December 2014).

The respiratory control of carbon dioxide in children and adolescents referred for treatment of psychogenic non-epileptic seizures

Psychogenic non-epileptic seizures (PNES) are a common problem in paediatric neurology and psychiatry that can best be understood as atypical responses to threat. Threats activate the body for action by mediating increases in arousal, respiration, and motor readiness. In previous studies, a range of cardiac, endocrine, brain-based, attention-bias, and behavioral measures have been used to demonstrate increases in arousal, vigilance, and motor readiness in patients with PNES. The current study uses respiratory measures to assess both the motor readiness of the respiratory system and the respiratory regulation of CO₂. Baseline respiratory rates during clinical assessment and arterial CO₂ levels during the hyperventilation component of routine video electroencephalogram were documented in 60 children and adolescents referred for treatment of PNES and in 50 controls. Patients showed elevated baseline respiratory rates [t(78) = 3.34, p = .001], with 36/52 (69%) of patients [vs. 11/28 (39%) controls] falling above the 75th percentile (χ² = 6.7343; df = 1; p = .009). Twenty-eight (47%) of patients [vs. 4/50 (8%) controls] showed a skewed hyperventilation-challenge profile—baseline PCO₂ <36 mmHg, a trough PCO₂ ≤ 20 mmHg, or a final PCO₂ <36 mmHg after 15 min of recovery—signaling difficulties with CO₂ regulation (χ² = 19.77; df = 1; p < .001). Children and adolescents with PNES present in a state of readiness-for-action characterized by high arousal coupled with activation of the respiratory motor system, increases in ventilation, and a hyperventilation-challenge profile shifted downward from homeostatic range. Breathing interventions that target arousal, decrease respiratory rate, and normalize ventilation and arterial CO₂ may help patients shift brain–body state and avert PNES episodes.

A prospective observational longitudinal study of new-onset seizures and newly diagnosed epilepsy in dogs

Background

Seizures are common in dogs and can be caused by non-epileptic conditions or epilepsy. The clinical course of newly diagnosed epilepsy is sparsely documented.

The objective of this study was to prospectively investigate causes for seizures (epileptic and non-epileptic) in a cohort of dogs with new-onset untreated seizures, and for those dogs with newly diagnosed epilepsy to investigate epilepsy type, seizure type and the course of disease over time, including the risk of seizure recurrence. Untreated client-owned dogs experiencing new-onset seizures were prospectively enrolled in a longitudinal observational study including clinical investigations and long-term monitoring at the Copenhagen University Hospital for Companion Animals. A baseline clinical assessment was followed by investigator/owner contact every eight weeks from inclusion to death or end of study. Inclusion of dogs was conducted from November 2010 to September 2012, and the study terminated in June 2014.

Results

One hundred and six dogs were included in the study. Seventy-nine dogs (74.5%) were diagnosed with epilepsy: 61 dogs (77.2%) with idiopathic epilepsy, 13 dogs (16.5%) with structural epilepsy and five dogs (6.3%) with suspected structural epilepsy. A non-epileptic cause for seizures was identified in 13 dogs and suspected in 10 dogs. Four dogs in which no cause for seizures was identified experienced only one seizure during the study. In dogs with idiopathic epilepsy 60% had their second epileptic seizure within three months of seizure onset. Twenty-six dogs with idiopathic epilepsy (43%) completed the study without receiving antiepileptic treatment. The natural course of idiopathic epilepsy (uninfluenced by drugs) was illustrated by highly individual and fluctuating seizure patterns, including long periods of remission. Cluster seizures motivated early treatment. In a few dogs with a high seizure frequency owners declined treatment against the investigators advice.

Conclusions

Epilepsy is the most likely diagnosis in dogs presenting with new-onset seizures. The course of idiopathic epilepsy is highly individual and might not necessarily require long-term treatment. This must be considered when advising owners about what to expect with regard to treatment and prognosis.

Diagnostic delay in psychogenic seizures and the association with anti-seizure medication trials

PURPOSE

The average delay from first seizure to diagnosis of psychogenic non-epileptic seizures (PNES) is over 7 years. The reason for this delay is not well understood. We hypothesized that a perceived decrease in seizure frequency after starting an anti-seizure medication (ASM) may contribute to longer delays, but the frequency of such a response has not been well established.

METHODS

Time from onset to diagnosis, medication history and associated seizure frequency was acquired from the medical records of 297 consecutive patients with PNES diagnosed using video-electroencephalographic monitoring. Exponential regression was used to model the effect of medication trials and response on diagnostic delay.

RESULTS

Mean diagnostic delay was 8.4 years (min 1 day, max 52 years). The robust average diagnostic delay was 2.8 years (95% CI: 2.2-3.5 years) based on an exponential model as 10 to the mean of log10 delay. Each ASM trial increased the robust average delay exponentially by at least one third of a year (Wald t=3.6, p=0.004). Response to ASM trials did not significantly change diagnostic delay (Wald t=-0.9, p=0.38).

CONCLUSION

Although a response to ASMs was observed commonly in these patients with PNES, the presence of a response was not associated with longer time until definitive diagnosis. Instead, the number of ASMs tried was associated with a longer delay until diagnosis, suggesting that ASM trials were continued despite lack of response. These data support the guideline that patients with seizures should be referred to epilepsy care centers after failure of two medication trials.

Biopsychosocial predictors of psychogenic non-epileptic seizures

BACKGROUND

Previous studies have identified numerous biological, psychological and social characteristics of persons with psychogenic non-epileptic seizures (PNES) however the strength of many of these factors have not been evaluated to determine which are predictive of the diagnosis compared to those that may only be stereotypes with limited clinical utility.

METHOD

A retrospective chart review of persons admitted to our epilepsy monitoring unit over a 6-year period was conducted to examine predictors of a video-EEG confirmed PNES diagnosis.

RESULTS

A total of 689 patients had events leading to a diagnosis, 47% (n=324) with PNES only, 12% (n=84) with PNES & Epilepsy and 41% (n=281) with Epilepsy only. Five biological predictors of a PNES only diagnosis were found; number of years with events (OR=1.10), history of head injury (OR=1.91), asthma (OR=2.94), gastro-esophageal reflux disease (OR=1.72) and pain (OR=2.25). One psychological predictor; anxiety (OR=1.72) and two social predictors; being married (OR=1.81) and history of physical/sexual abuse (OR=3.35). Two significant biological predictors of a PNES & Epilepsy diagnosis were found; migraine (OR=1.83) and gastro-esophageal reflux disease (OR=2.17).

CONCLUSIONS

Our findings support the importance of considering the biopsychosocial model for the diagnosis and treatment of PNES or PNES with concomitant epilepsy.

Large-field repetitive transcranial magnetic stimulation with circular coil in the treatment of functional neurological symptoms

OBJECTIVE

Patients with functional neurological symptoms (FNS) are frequently encountered by neurologists and are difficult to treat. Symptoms are multiple and may appear concurrently or successively in the same patient. To date, few studies have been published on focal repetitive transcranial magnetic stimulation (rTMS) in FNS. This type of stimulation induces a focal current, vertically in the cortex. Results are contradictory, probably because it is difficult to identify a limited cortical area that triggers these symptoms. We assessed the efficacy of another type of rTMS: large-field stimulation by means of a circular coil covering a surface area approximately 20 times greater and inducing a circular current tangentially to the cortex.

PUBLISHED STUDIES

We analysed two studies on the efficacy of large-field rTMS in functional paralysis and in functional movement disorders. The efficacy of large-field rTMS was very marked in these two studies.

PERSONAL NON-PUBLISHED STUDIES

We reported several open series, including patients with functional sensory loss, functional visual loss, and non-epileptic seizures.

METHOD

For all patients, one or several sessions of 60 stimuli with circular coil were carried out with a protocol depending on the symptoms.

RESULTS

The efficacy of large-field rTMS was dramatic in all patient series. Additionally, we discuss the possible involved mechanism: placebo effect, cognitive behavioural effect or neuromodulatory effect.

CONCLUSION

According to the data from these different studies, large-field rTMS could be a new therapy for patients with FNS. However, controlled studies are mandatory.