Nonepileptic attack disorder and functional movement disorder: A clinical continuum?

Diagnostic Value of Bereitschaftspotential in People With Functional Seizures

PURPOSE

Bereitschaftspotential (BP) or readiness potential in people with functional movement disorders can aid diagnostic workup. We evaluated the diagnostic value of BP as an interictal EEG marker in people with functional seizures (FS).

METHODS

We recorded and analyzed BP interictal before intended movements in 17 adults with FS and 17 controls with alternative diagnoses. We evaluated the signals for the presence of BP, latency, amplitude, and early versus late BP.

RESULTS

Bereitschaftspotential was present in all except one person with FS. We found no significant differences in the latency and amplitude of BP between participants with FS and controls. The early BP showed the most significant variance in amplitude, latency, and presence.

CONCLUSIONS

We found interictal typical BP values in participants with FS and variable semiology, while earlier research found interictal no BP in functional movement disorders. These findings do not support the use of BP as an interictal diagnostic tool for FS. Differences in early BP and focus on FS with pure motor semiology are starting points for further research evaluating potential interictal markers in people with FS.

Beyond movement: Headache in patients with functional movement disorders

OBJECTIVE

To evaluate headache comorbidity in a cohort of patients with functional movement disorders by assessing the prevalence, clinical characteristics, and temporal relationship of headache with the onset of functional symptoms.

BACKGROUND

Functional movement disorders are common and potentially treatable. Although headache is frequent in these patients, few studies have evaluated their headache features.

METHODS

This observational cohort study included consecutive patients with functional movement disorders evaluated in our Functional Movement Disorders Unit between October 2021 and November 2022. Clinical and demographic features from clinical charts were reviewed, and patients completed a self-administered questionnaire designed by the authors that included headache characteristics, disease duration, treatments received, and the Headache Impact Test-6. Headache type was classified as per the Classification of Headache Disorders, third edition (ICHD-3).

RESULTS

A total of 51 patients with functional movement disorders were included. Of those, 40 (78%) reported having recurrent headache. Headache intensity was moderate-severe in 33/40 (83%), and about two-thirds experienced headache >9 days/month. Disability secondary to headache was high (median [interquartile range] Headache Impact Test-6 score 62 [49-66]). Based on the ICHD-3, 23/40 (58%) of patients with headache met the criteria for migraine or probable migraine, 11/40 (27%) for tension-type headache, two of 40 (5%) for new daily persistent headache, and one of 40 (3%) for primary exercise headache, while three of 40 (7%) were unclassifiable. The onset of headache occurred before the functional movement disorder in 28/40 (70%), after the functional movement disorder in five of 40 (12%), and simultaneously in six of 40 (15%). In this last group, four of the six (67%) patients described a daily headache from the onset, and two met the criteria for new daily persistent headache.

CONCLUSIONS

Headache is a frequent condition in patients with functional movement disorders and an additional burden of disability beyond their motor symptoms. We found that, besides migraine and tension-type headache, new daily persistent headache may be a comorbid phenotype in patients with functional movement disorders and should be further studied in larger prospective studies.

Functional neurological disorder, physical activity and exercise: What we know and what we can learn from comorbid disorders

Functional neurological disorder (FND) is a common neurologic disorder associated with many comorbid symptoms including fatigue, pain, headache, and orthostasis. These concurrent symptoms lead patients to accumulate multiple diagnoses comorbid with FND, including fibromyalgia, chronic fatigue syndrome, postural orthostatic tachycardia syndrome, persistent post-concussive symptoms, and chronic pain. The role of physical activity and exercise has not been evaluated in FND populations, though has been studied in certain comorbid conditions. In this traditional narrative literature review, we highlight some existing literature on physical activity in FND, then look to comorbid disorders to highlight the therapeutic potential of physical activity. We then consider abnormalities in the autonomic nervous system (ANS) as a potential pathophysiological explanation for symptoms in FND and comorbid disorders and postulate how physical activity and exercise may provide benefit via autonomic regulation.

Functional Tic-like Behaviors: From the COVID-19 Pandemic to the Post-Pandemic Era

During the COVID-19 pandemic, there have been multiple reports about an unforeseen surge in adolescents and young adults exhibiting sudden onset functional tic-like behaviors. This phenomenon has been mainly associated with the female gender and occasionally after exposure to social media content featuring similar patterns of functional tic-like behaviors. A significant portion of these individuals have been directed to specialist clinics for movement disorders with initial misdiagnoses of late-onset refractory Tourette syndrome. Distinguishing between rapid onset functional tic-like behaviors and neurodevelopmental tics as part of Tourette syndrome can be challenging; however, the differential diagnosis is facilitated by focusing on specific clinical and demographic factors, which we have explored in a systematic literature review. Compared to neurodevelopmental tics, functional tic-like behaviors typically present with a more abrupt and intense manifestation of symptoms, onset at a later age, higher prevalence among females, inability to suppress tics, coexisting anxiety and depression, and sometimes a history of exposure to social media content portraying tic-like behaviors of a similar nature. This novel manifestation of a functional neurological disorder may thus be viewed as an emerging neuropsychiatric condition potentially triggered/exacerbated by the psychosocial repercussions of the COVID-19 crisis.

Functional tics: Expanding the phenotypes of functional movement disorders?

BACKGROUND AND PURPOSE

Until the outbreak reported during the COVID-19 pandemic, functional tics were considered to be a relatively rare clinical phenotype, as opposed to other functional movement disorders such as functional tremor and dystonia. To better characterize this phenotype, we compared the demographic and clinical characteristics of patients who developed functional tics during the pandemic and those of patients with other functional movement disorders.

METHODS

Data from 110 patients were collected at the same neuropsychiatry centre: 66 consecutive patients who developed functional tics without other functional motor symptoms or neurodevelopmental tics and 44 patients with a mix of functional dystonia, tremor, gait, and myoclonus.

RESULTS

Both groups were characterized by female sex preponderance (70%-80%) and (sub)acute onset of functional symptoms (~80%). However, patients with functional tics had a significantly earlier age at onset of functional symptoms (21 vs. 39 years). Exposure to relevant social media content was reported by almost half of the patients with functional tics, but by none of the patients with other functional movement disorders. Comorbidity profiles were similar, with relatively high rates of anxiety/affective symptoms and other functional neurological symptoms (nonepileptic attacks).

CONCLUSIONS

Patients who developed functional tics during the pandemic represent a phenotypic variant of the wider group of patients with functional movement disorders, associated with younger age at onset and influenced by pandemic-related factors, including increased exposure to specific social media content. Diagnostic protocols and treatment interventions should be tailored to address the specific features of this newly defined phenotype.

Neurodevelopmental versus functional tics: A controlled study

BACKGROUND

An unprecedented increase in newly developed functional tics, mainly in young females, has been reported during the COVID-19 pandemic. We set out to complement existing case series with the largest controlled study to date on the clinical phenomenology of functional tics versus neurodevelopmental tics.

METHODS

Data from 166 patients were collected at a specialist clinic for tic disorders during a three-year period overlapping with the COVID-19 pandemic (2020-2023). We compared the clinical features of patients who developed functional tics during the COVID-19 pandemic (N = 83) to patients with Tourette syndrome matched for age and gender (N = 83).

RESULTS

Female adolescents and young adults accounted for 86% of the clinical sample of patients with functional tics, who were less likely to report a family history of tic disorders than their matched controls with Tourette syndrome. Co-morbidity profiles were significantly different: anxiety and other functional neurological disorders were more strongly associated with functional tics, whereas attention-deficit and hyperactivity disorder and tic-related obsessive-compulsive behaviors co-occurred more frequently with neurodevelopmental tics. Overall, absence of tic-related obsessive-compulsive behaviors (t = 8.096; p < 0.001) and absence of a family history of tics (t = 5.111; p < 0.001) were the strongest predictors of the diagnosis of functional tics. Compared to neurodevelopmental tics, functional tics were more likely to present acutely/subacutely at a later age (21 versus 7 years), without a clear rostro-caudal progression. Coprophenomena, self-injurious behaviors, and complex clinical manifestations such as blocking tics, throwing tics, and tic attacks, were all over-represented in the functional group.

CONCLUSIONS

Our findings provide robust confirmation of both patient-related variables and tic characteristics contributing to the differential diagnosis between functional tics developed during the pandemic and neurodevelopmental tics reported by patients with Tourette syndrome.

Psychogenic non-epileptic seizures and functional motor disorders in developmental age: A comparison of clinical and psychopathological features

BACKGROUND

Psychogenic Non-Epileptic Seizures (PNES) and Functional Motor Disorders (FMDs) commonly represent the main clinical manifestations of Functional Neurological Disorders (FNDs). Despite their high prevalence in pediatric neurological services, literature on this topic is still spare for this population. The present study aimed to deepen the clinical knowledge of a pediatric FNDs sample through a demographic and clinical characterization of the most recurrent clinical patterns during the pediatric age. Moreover, a comparison of neuropsychological and psychopathological profiles of PNES and FMD patients was carried out to identify specific vulnerabilities and therapeutic targets linked with these different clinical manifestations.

MATERIALS AND METHODS

A total of 43 FNDs patients (age range 7-17 years old) were retrospectively included in our study, enrolled in two subgroups: 20 with FMDs and 23 with PNES diagnosis. They were inpatients and outpatients referred over a period of 5 years and a standardized neurological, neuropsychological (WISC-IV/WAIS-IV), and psychiatric (CDI-2, MASC-2, ADES, DIS-Q, PID-5) evaluation was assessed.

RESULTS

In PNES patients the most common clinical phenotypes were functional tonic-clonic (52%) and atonic (32%) manifestations while in the FMDs group were gait alterations (60%), functional myoclonus (35%), and tremor (35%). A higher frequency of cognitive impairment was reported in PNES patients with higher anxiety-depressive symptom rates than FMDs patients.

CONCLUSIONS

Notably, specific neurocognitive and psychopathological profiles were described in PNES and FMDs, highlighting higher cognitive and psychiatric vulnerabilities in PNES, suggesting as well different strategy for therapeutic approaches.

Diagnosis and Initial Treatment of Functional Movement Disorders in Children

Functional movement disorders (FMD) are complex neurobehavioral disorders that can be a significant source of disability for both children and their caregivers. While FMD in the adult population is better characterized, the aim of this paper is to review the pertinent clinical and historical features, diagnostic criteria, and multi-disciplinary management of FMD in the pediatric population. We highlight recent trends in pediatric FMD, including the increase in functional tic-like behaviors that has been observed during the COVID-19 pandemic.

[Development and content validation of a questionnaire for functional movement disorders]

Von Kriegszitterern zu Teenies mit TikTok-Tics – funktionelle Bewegungsstörungen galten lange als motorischer Ausdruck seelischer Turbulenzen. Tatsächlich werden psychodynamische Modelle jedoch zunehmend durch neurophysiologische Erkenntnisse ergänzt, sodass die Kombination von Psychotherapie mit spezialisierter Physiotherapie an Bedeutung gewinnt. Bislang existiert allerdings kein störungsspezifisches Ergebnismaß, welches patientenrelevante Aspekte dieser vielfältigen Störung adäquat abbildet. Ein erster derartiger Fragebogen wurde entwickelt und in einem mehrstufigen Entwicklungsprozess inhaltlich validiert. Relevanz und Verständlichkeit der Items wurden zuerst durch ein Expertengremium und anschließend durch betroffene Patienten evaluiert und entsprechend angepasst. Der so konstruierte Fragebogen erlaubt erstmals eine inhaltlich valide Quantifizierung der subjektiven Beschwerden und Auswirkungen funktioneller Bewegungsstörungen. Als Nächstes erfolgt eine multizentrische teststatistische Validierung.

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.