The association of panic and hyperventilation with psychogenic non-epileptic seizures: A systematic review and meta-analysis

Dissimilar Changes in Serum Cortisol after Epileptic and Psychogenic Non-Epileptic Seizures: A Promising Biomarker in the Differential Diagnosis of Paroxysmal Events?

The hypothalamic-pituitary-adrenal axis is known to be involved in the pathogenesis of epilepsy and psychiatric disorders. Epileptic seizures (ESs) and psychogenic non-epileptic seizures (PNESs) are frequently differentially misdiagnosed. This study aimed to evaluate changes in serum cortisol and prolactin levels after ESs and PNESs as possible differential diagnostic biomarkers. Patients over 18 years with ESs (n = 29) and PNESs with motor manifestations (n = 45), captured on video-EEG monitoring, were included. Serum cortisol and prolactin levels as well as hemograms were assessed in blood samples taken at admission, during the first hour after the seizure, and after 6, 12, and 24 h. Cortisol and prolactine response were evident in the ES group (but not the PNES group) as an acute significant increase within the first hour after seizure. The occurrence of seizures in patients with ESs and PNESs demonstrated different circadian patterns. ROC analysis confirmed the accuracy of discrimination between paroxysmal events based on cortisol response: the AUC equals 0.865, with a prediction accuracy at the cutoff point of 376.5 nmol/L 0.811 (sensitivity 86.7%, specificity 72.4%). Thus, assessments of acute serum cortisol response to a paroxysmal event may be regarded as a simple, fast, and minimally invasive laboratory test contributing to differential diagnosis of ESs and PNESs.

Does Hyperventilation Increase the Diagnostic Yield of the Routine Electroencephalogram: A Retrospective Analysis of Adult and Pediatric Cohorts

PURPOSE

While hyperventilation (HV) increases the diagnostic yield of EEG in children, there is conflicting evidence to support its application in adults. For the first time in history, a large cohort of patients has undergone EEGs without HV during the COVID-19 pandemic. Utilizing this opportunity, we sought to investigate whether HV increases the diagnostic yield of EEG in children compared with adults.

METHODS

Patients aged six years and above who had routine EEGs at Monash Health between January 2019 and December 2020 were studied. The cohort was divided into two, pediatric (younger than 18 years) and adult (18 years or older). Epileptiform abnormalities (ictal and interictal) were the outcomes investigated. The effect of HV was examined with logistic regression to determine odds ratios with 95% confidence intervals.

RESULTS

In total, we studied 3,273 patients (pediatric = 830, adult = 2,443). In the pediatric cohort, HV significantly increased the diagnostic yield of absence seizures (p = 0.01, odds ratios 2.44, 95% confidence intervals 1.21-4.93). In adults, HV did not increase the yield of absence seizures (p = 0.34, odds ratios 0.36, 95% confidence intervals 0.05-2.88). Interictal epileptiform discharges during HV were significantly more frequent in children compared with adults (p < 0.001, odds ratios 3.81, 95% confidence intervals 2.51-5.77).

CONCLUSIONS

Hyperventilation is useful to increase the yield of interictal epileptiform discharges and absence seizures in pediatric patients but not in adults. Hence, routine EEG may be recorded in adults without HV when it is unsafe to perform.

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.

Understanding Functional Neurological Disorder: Recent Insights and Diagnostic Challenges

Functional neurological disorder (FND), formerly called conversion disorder, is a condition characterized by neurological symptoms that lack an identifiable organic purpose. These signs, which can consist of motor, sensory, or cognitive disturbances, are not deliberately produced and often vary in severity. Its diagnosis is predicated on clinical evaluation and the exclusion of other medical or psychiatric situations. Its treatment typically involves a multidisciplinary technique addressing each of the neurological symptoms and underlying psychological factors via a mixture of medical management, psychotherapy, and supportive interventions. Recent advances in neuroimaging and a deeper exploration of its epidemiology, pathophysiology, and clinical presentation have shed new light on this disorder. This paper synthesizes the current knowledge on FND, focusing on its epidemiology and underlying mechanisms, neuroimaging insights, and the differentiation of FND from feigning or malingering. This review highlights the phenotypic heterogeneity of FND and the diagnostic challenges it presents. It also discusses the significant role of neuroimaging in unraveling the complex neural underpinnings of FND and its potential in predicting treatment response. This paper underscores the importance of a nuanced understanding of FND in informing clinical practice and guiding future research. With advancements in neuroimaging techniques and growing recognition of the disorder's multifaceted nature, the paper suggests a promising trajectory toward more effective, personalized treatment strategies and a better overall understanding of the disorder.

Dissociative seizures in the emergency room: room for improvement

BACKGROUND

Dissociative seizures, also known as functional or psychogenic non-epileptic seizures, account for 11%-27% of all emergency seizure presentations. Misdiagnosis as epileptic seizures is common and leads to ineffective and potentially harmful treatment escalations. We assess the potential for diagnostic improvement at different stages of emergency workup and estimate the utility of benzodiazepines.

METHODS

A retrospective study of all emergency presentations with a discharge diagnosis of acute dissociative seizures seen at a university hospital 2010-2022 was performed to assess clinical characteristics and emergency decision-making.

RESULTS

Among 156 patients (73% female, median 29 years), 15% presented more than once for a total of 203 presentations. Half of seizures were ongoing at first medical contact; prolonged seizures and clusters were common (23% and 24%). Diagnostic accuracy differed between on-site emergency physicians and emergency department neurologists (12% vs 52%). Typical features such as eye closure, discontinuous course and asynchronous movements were common. Benzodiazepines were given in two-thirds of ongoing seizures, often in high doses and preferentially for major hyperkinetic semiology. Clinical response to benzodiazepines was mixed, with a minority of patients remaining either unaffected (16%) or becoming critically sedated (13%). A quarter of patients given benzodiazepines by emergency medical services were admitted to a monitoring unit, 9% were intubated.

CONCLUSIONS

Improved semiological assessment could reduce early misdiagnosis of dissociative seizures. Although some seizures seem to respond to benzodiazepines, critical sedation is common, and further studies are needed to assess the therapeutic ratio.

An investigation into mothers' experiences of their children's functional tic-like behaviour and tic attacks

OBJECTIVE

This is the first study to systematically explore the lived experiences of sudden and new onset of severe functional tics from the perspective of the mother's experiences and describes their attempts to access support services in the United Kingdom.

METHOD

Twenty-One mothers of young people aged between 12 to 17 years with functional tic-like behaviour (FTLB) took part in semi-structured interviews. Thematic analysis of the transcribed interviews revealed gaps and inconsistencies within the process of gaining access to professional services and a lack of support for the management of tics and functional tic-like movements, in addition to highlighting the impact it had on daily family life.

RESULTS

The themes generated included the occurrence and development of tics, the severity and intensity of symptoms, the psychological impact on the family and the need to make recommendations for a clear care pathway. Managing the impact of the FTLB and co-occurring conditions such as suicidal ideation and self-harm, as well as the physical and emotional trauma, commonly contributed to feelings of isolation and helplessness, which impacted negatively on the family's ability to function and participate in society.

CONCLUSIONS

The findings emphasize the urgent need to create a clear management pathway for those experiencing FTLB, including the need for more professionals with relevant knowledge, to improve the dialogue with families during the referral process, whilst prioritising the treatment of anxiety and other identified mental health concerns.

Toward a Precision Medicine Approach to the Outpatient Assessment and Treatment of Functional Neurological Disorder

Functional neurological disorder (FND) is a neuropsychiatric condition. In this field, prospective psychotherapy trials and consensus recommendations for physiotherapy, occupational therapy, and speech language therapy have been published. However, significant clinical complexities remain. "Rule in" signs - while critical for making a positive diagnosis - do not equate to a personalized treatment plan in many instances. Here, we propose that the neuropsychiatric assessment and real-time development of a work-in-progress biopsychosocial clinical formulation aids the development of a patient-centered outpatient treatment plan. This precision medicine approach is based on the literature, expert opinions and our clinical experience working in an interdisciplinary FND service.

Prevalence of autistic traits in functional neurological disorder and relationship to alexithymia and psychiatric comorbidity

INTRODUCTION

In a cohort of adults with Functional Neurological Disorder (FND), we aim to: METHODS: 91 patients participating in a FND 5-week outpatient program completed baseline self-report questionnaires for total phobia, somatic symptom severity, attention deficit hyperactivity disorder (ADHD) and dyslexia. Patients were grouped by Autism Spectrum Quotient (AQ-10) score of <6 or ≥ 6 and compared for significant differences in tested variables. This analysis was repeated with patients grouped by alexithymia status. Simple effects were tested using pairwise comparisons. Multistep regression models tested direct relationships between autistic traits and psychiatric comorbidity scores, and mediation by alexithymia.

RESULTS

36 patients (40%) were AQ-10 positive (scoring ≥6 on AQ-10). A further 36 patients (across AQ-10 positive and AQ-10 negative groups) (40%) screened positive for alexithymia. AQ-10 positive patients scored significantly higher for alexithymia, depression, generalised anxiety, social phobia, ADHD, and dyslexia. Alexithymia positive patients scored significantly higher for generalised anxiety, depression, somatic symptoms severity, social phobia, and dyslexia. Alexithymia score was found to mediate the relationship between autistic trait and depression scores.

CONCLUSION

We demonstrate a high proportion of autistic and alexithymic traits, in adults with FND. A higher prevalence of autistic traits may highlight a need for specialised communication approaches in FND management. Mechanistic conclusions are limited. Future research could explore links with interoceptive data.

Linking gene expression patterns and brain morphometry to trauma and symptom severity in patients with functional seizures

Within stress-diathesis models, adverse life experiences (ALEs) increase the susceptibility to functional neurological symptoms through neuroplasticity effects. We aimed to characterize potential genetic influences on this relationship in 20 patients with functional seizures. Questionnaires, structural MRIs and Allen Human Brain Atlas gene expression information were used to probe the intersection of symptom severity (Somatoform Dissociation Questionnaire, SDQ-20), ALE burden, and gray matter volumes. SDQ-20 scores positively correlated with sexual trauma, emotional neglect, and threat to life experiences. Higher SDQ-20 scores related to lower bilateral insula, left orbitofrontal, right amygdala, and perigenual/posterior cingulate volumes. Higher sexual trauma burden correlated with lower right posterior insula and putamen volumes; higher emotional neglect related to lower bilateral insula/right amygdala volumes. Findings in left insula/ventral precentral gyrus (SDQ-20), right insula/putamen (sexual trauma), and right amygdala (emotional neglect) held when controlling for comorbid psychopathology. At the intersection of symptom severity and sexual trauma volumetric findings, genes overrepresented in adrenergic, serotonergic, and oxytocin receptor signaling as well as in cortical and amygdala development were spatially correlated. In conclusion, ALEs and symptom severity were associated with gray matter volumes in cingulo-insular and amygdala areas, spatially overlapping with expression patterns of genes involved in stress-related signaling and neurodevelopment.

Triggers in functional motor disorder: a clinical feature distinct from precipitating factors

Background and objective

People with functional motor disorder (FMD) report triggers—sensory or motor-induced stimuli that exacerbate or initiate paroxysmal occurrences of their movement disorder. These are a distinct phenomenon from precipitating factors occurring at the initial onset of the disorder. We aimed to assess triggers in FMD and understand their relevance to paroxysmal variability often seen in FMD.

Methods

We enrolled consecutive outpatients with a definite diagnosis of FMD. Each patient underwent a detailed clinical evaluation also including the presence of trigger factors and video-recordings both during neurological examination and physiotherapy treatment. Patients were classified as having “triggers” (T-FMD) or “not having triggers” (NoT-FMD) as well as “paroxysmal” compared to “persistent with paroxysmal variability”.

Results

The study sample was 100 patients (82% female) with FMD; the mean age at onset was 41 years. Triggers were observed in 88% of patients and in 65 of these the FMD was pure paroxysmal. The most common triggers were movement or physical exercise, followed by emotional, visual, touch, and auditory stimuli; 39 (44%) were isolated and 49 (56%) were combined triggers. Among the T-FMD patients, FMD were paroxysmal in 74% (n = 65) and persistent with paroxysmal variability in 26% (n = 23). The T-FMD patients were younger (p = 0.016) and had a gait disorder (p = 0.035) more frequently than the NoT-FMD patients.

Discussion

Triggers are frequent in FMD and may have diverse overlapping clinical presentations. In this sample, FMD was most often paroxysmal, suggesting the value of noting triggers as clinical clues in the diagnosis and rehabilitation of FMD.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11102-1.

Functional neurological disorder: new subtypes and shared mechanisms

Functional neurological disorder is common in neurological practice. A new approach to the positive diagnosis of this disorder focuses on recognisable patterns of genuinely experienced symptoms and signs that show variability within the same task and between different tasks over time. Psychological stressors are common risk factors for functional neurological disorder, but are often absent. Four entities-functional seizures, functional movement disorders, persistent perceptual postural dizziness, and functional cognitive disorder-show similarities in aetiology and pathophysiology and are variants of a disorder at the interface between neurology and psychiatry. All four entities have distinctive features and can be diagnosed with the support of clinical neurophysiological studies and other biomarkers. The pathophysiology of functional neurological disorder includes overactivity of the limbic system, the development of an internal symptom model as part of a predictive coding framework, and dysfunction of brain networks that gives movement the sense of voluntariness. Evidence supports tailored multidisciplinary treatment that can involve physical and psychological therapy approaches.

Seizure phobia: A distinct psychiatric disorder among people with epilepsy

OBJECTIVE

Epilepsy is characterized by unpredictable attacks. Hence, people with epilepsy (PWE) may develop anxious anticipation of upcoming seizures. Seizure phobia is an anxiety disorder wherein seizure anticipatory situations trigger fear, accompanied by avoidance behaviors. Research on seizure phobia among PWE is scarce. Therefore, we aimed to describe the diagnosis of seizure phobia and its association with demographic, psychiatric and neurological variables.

METHODS

This is a cross-sectional study of adult PWE in a tertiary epilepsy outpatient clinic. Data were collected from semi-structured interviews, demographic questionnaires and medical records. Patients with and without seizure phobia were compared in terms of sociodemographic, psychiatric, and neurological variables. A logistic regression analysis was performed to identify variables that predicted seizure phobia.

RESULTS

Among 69 PWE included in the study, 19 (27.5%) were diagnosed with seizure phobia. In comparison with PWE without seizure phobia, PWE with seizure phobia were predominantly female (84.2% vs 44.2%, p = 0.005), and had more comorbid anxiety disorders (84.2% vs 34.9%, p = 0.01), past major depressive episode (MDE) (63.2% vs 20.9%, p = 0.003), and post-traumatic stress disorder (26.3% vs 7%, p = 0.05). There was a significant association between seizure phobia and comorbid psychogenic non-epileptic seizures (36.8% vs 11.6%, p = 0.034). However, no significant association was found with epilepsy-related variables. A multivariate logistic regression model indicated anxiety and a past MDE as predictive factors for seizure phobia (R² = 0.43).

CONCLUSION

Seizure phobia is a distinct psychiatric entity among PWE. Further research is required to understand its etiology, risk factors, and potential interventions for these patients.

Epilepsy and other seizure disorders in acute psychiatric inpatients

BACKGROUND

It is well known that patients with epilepsy have a high rate of psychiatric comorbidity. However, studies exploring epilepsy in psychiatric cohorts are scarce. The aim of this study was to examine the prevalence of seizure disorders in acute psychiatric inpatients.

METHODS

This is a cross-sectional study performed in a catchment-area based acute psychiatric department. All patients (age > 18) admitted during September 2011 - March 2012 were eligible for inclusion. Consenting patients were screened for a life-time history of epilepsy or seizures using self-reported questionnaire data and diagnostic codes for epilepsy in hospital and National registries. Patients scoring positive to one or more of these screening criteria underwent a thorough diagnostic validation (chart review), and the seizure disorders were classified as epilepsy, acute symptomatic seizures and/or psychogenic non-epileptic seizures according to current definitions.

RESULTS

A total of 380 out of 591 (64.3%) consecutively admitted patients consented to participate in the study. Eighty-nine patients (23.4%) scored positive to one or more screening criteria. Fifteen (3.9%) were classified with epilepsy, 21 (5.5%) with acute symptomatic seizures and 9 (2.4%) with psychogenic non-epileptic seizures.

CONCLUSIONS

This is the first study to report on the prevalence of seizure disorders in acute psychiatric inpatients. The life-time prevalence of epilepsy in this cohort of patients is five - six times as high as reports in the general population. These findings underscore the need for the clinical psychiatrist to have comprehensive knowledge on the interface between epileptology and psychiatry.

TRIALS REGISTRATION

ClinicalTrials.gov identifier NCT01415323 .

Functional seizures are not less important than epilepsy

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People with functional seizures often suffer from psychiatric comorbidities.

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People with FS report detrimental effects on social aspects of their lives.

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FS are associated with a considerable direct and indirect economic burden.

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FS have increased rates of mortality compared to healthy controls.

Functional seizures (FS) are frequently encountered in neurology clinics, often affect young adults, and have significant negative impacts on many aspects of a person’s life. In the current narrative review, we searched the literature regarding some of the consequences of FS (i.e., psychiatric comorbidities, social consequences, costs that are associated with the condition, cognitive impairment in patients with FS, the quality of life of the people with FS, and the increased risk of mortality that is associated with FS). Evidence shows that FS have significant negative consequences, comparable in their magnitude to those affecting patients with epilepsy. The clinical and scientific communities should take steps to address these consequences through clinical care and research that prioritizes, facilitates, and expedites evidence-based diagnosis and treatment for FS.

A framework for understanding the pathophysiology of functional neurological disorder

The symptoms of functional neurological disorder (FND) are a product of its pathophysiology. The pathophysiology of FND is reflective of dysfunction within and across different brain circuits that, in turn, affects specific constructs. In this perspective article, we briefly review five constructs that are affected in FND: emotion processing (including salience), agency, attention, interoception, and predictive processing/inference. Examples of underlying neural circuits include salience, multimodal integration, and attention networks. The symptoms of each patient can be described as a combination of dysfunction in several of these networks and related processes. While we have gained a considerable understanding of FND, there is more work to be done, including determining how pathophysiological abnormalities arise as a consequence of etiologic biopsychosocial factors. To facilitate advances in this underserved and important area, we propose a pathophysiology-focused research agenda to engage government-sponsored funding agencies and foundations.

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.

Preictal autonomic dynamics in psychogenic nonepileptic seizures

OBJECTIVES

Psychogenic nonepileptic seizures (PNES) resemble seizures but are psychological in origin. The etiology of PNES remains poorly understood, yet several theories argue for the importance of autonomic dysregulation in its pathophysiology. We therefore conducted a retrospective study to investigate autonomic dynamics leading up to a seizure to inform their mechanistic relevance.

METHODS

One hundred one patients with PNES and 45 patients with epileptic seizure (ES) were analyzed for preictal heart rate (HR) and respiratory rate (RR) at baseline and at minute intervals from 5 min to onset.

RESULTS

Patients with PNES showed rising HR (p < 0.001, repeated-measures analysis of variance (ANOVA)) and rising RR (p = 0.012, repeated-measures ANOVA) from baseline to the onset of their seizures. Patients with ES did not exhibit significant preictal HR or RR increase. Patients with PNES had nonsignificantly higher preictal HR and RR than patients with ES.

SIGNIFICANCE

Patients with PNES exhibit increasing autonomic arousal prior to seizure events unlike patients with epilepsy. This may reflect increasing levels of preictal anxiety, and future studies could study patients' subjective experiences of the preictal period, and more definitive measures of ventilation to see if this supported a model of PNES as "panic without panic".