Outcome Measures for Functional Neurological Disorder: A Review of the Theoretical Complexities

Agreement and disagreement in pediatric functional neurological symptom disorders: Comparing patient reported outcome measures (PROMs) and clinician assessments

Youth with functional neurological symptom disorder (FNSD) often perceive themselves as having limited capabilities, which may not align with clinical evaluations. This study assessed the disparities between clinician evaluations and patient-reported outcome measures (PROMs) regarding pain, motor function, and learning difficulties in youth with FNSD. Sixty-two youths with FNSD participated in this study, all of whom reported experiencing pain, motor problems, and/or learning difficulties. Clinicians also assessed these domains, resulting in a two-by-two categorization matrix: (1) agreement: child and clinician report "problems"; (2) agreement: child and clinician report "no problems"; (3) disagreement: child reports "problems" while the clinician does not; and (4) disagreement: clinician reports "problems" while the child does not. Agreement/disagreement differences were analyzed. No significant differences in prevalence were observed between the evaluators regarding pain (clinician-85%, child-88%), motor (clinician-98%, child-95%), or learning problems (clinician-69%, child-61%). More than 80% of the children and clinicians report pain and motor disorders. Instances in which children and clinicians reported learning problems (40.3%) exceeded cases in which both reported no problems (9.6%) or only the child reported problems (20.9%). Overall, the agreement between pain and motor function assessments was high (>90%), whereas that concerning learning difficulties was moderate (49.9%). Disagreement in pain/motor assessments was minimal (<5%), whereas for learning difficulties, disagreement rates were high (>20%). In conclusion, a significant concordance exists between PROMs and clinician assessments of pain and motor problems. However, the higher frequency of disagreements regarding learning difficulties emphasizes the importance of incorporating patient and clinician evaluations in pediatric FNSD treatment.

Specialist physiotherapy for functional motor disorder in England and Scotland (Physio4FMD): a pragmatic, multicentre, phase 3 randomised controlled trial

BACKGROUND

Functional motor disorder-the motor variant of functional neurological disorder-is a disabling condition that is commonly associated with poor health outcomes. Pathophysiological models have inspired new treatment approaches such as specialist physiotherapy, although evidence from large randomised controlled trials is absent. We aimed to assess the clinical effectiveness of a specialist physiotherapy intervention for functional motor disorder compared with treatment as usual.

METHODS

In this pragmatic, multicentre, phase 3 randomised controlled trial at 11 hospitals in England and Scotland, adults with a clinically definite diagnosis of functional motor disorder, diagnosed by a neurologist, were included. Participants were randomly assigned (1:1, stratified by site) using a remote web-based application to either specialist physiotherapy (a protocolised intervention of nine sessions plus follow-up) or treatment as usual (referral to local community neurological physiotherapy). Individuals working on data collection and analysis were masked to treatment allocation. The primary outcome was the physical functioning domain of the 36-item short form health questionnaire (SF36) at 12 months after randomisation. The primary analysis followed a modified intention-to-treat principle, using a complete case approach; participants who were unable to receive their randomised treatment due to the suspension of health-care services during the COVID-19 pandemic were excluded from the primary analysis. This trial is registered with the International Standard Randomised Controlled Trial registry, ISRCTN56136713, and is completed.

FINDINGS

Recruitment occurred between Oct 19, 2018, and March 11, 2020, pausing during the COVID-19 lockdown, and resuming from Aug 3, 2021, to Jan 31, 2022. Of 355 participants who were enrolled, 179 were randomly assigned to specialist physiotherapy and 176 to treatment as usual. 89 participants were excluded from the primary analysis due to COVID-19 interruption to treatment (27 were assigned to specialist physiotherapy and 62 to treatment as usual). After accounting for withdrawals (n=11) and loss to follow-up (n=14), the primary analysis included data from 241 participants (138 [91%] assigned specialist physiotherapy and 103 [90%] assigned treatment as usual). Physical functioning, as assessed by SF36, did not differ significantly between groups (adjusted mean difference 3·5, 95% CI -2·3 to 9·3; p=0·23). There were no serious adverse events related to the trial interventions. 35 serious adverse events were recorded in the specialist physiotherapy group by 24 participants (17·0%), and 24 serious adverse events were recorded in the treatment as usual group by 18 participants (17·0%); one death occurred in the specialist physiotherapy group (cause of death was recorded as suicide). All were considered unrelated to specialist physiotherapy.

INTERPRETATION

Although more participants who were assigned specialist physiotherapy self-rated their motor symptoms as improved and had better scores on subjective measures of mental health, the intervention did not result in better self-reported physical functioning at 12 months. Both the specialist and community neurological physiotherapy appeared to be a safe and a valued treatment for selected patients with functional motor disorder. Future research should continue to refine interventions for people with functional motor disorder and develop evidence-based methods to guide treatment triage decisions.

FUNDING

National Institute for Health and Care Research and Health Technology Assessment Programme.

Sleepiness and comorbid sleep disorders in functional motor disorders: a comparative study with central hypersomnia

Sleep symptoms, including excessive sleepiness, are frequently reported by patients with functional motor disorders (FMD). We aimed to classify the comorbid sleep disorders in FMD, and to investigate the relationship between subjective sleepiness and objective measures of hypersomnia, comparing them with data from people with central hypersomnia. A total of 37 patients (mean [SD] age 46.4 [11.2] years) with clinically definite FMD, and 17 patients (mean [SD] age 41.1 [11.6] years) with central hypersomnia underwent structured medical and sleep history, neurological examination, polysomnography, multiple sleep latency test (MSLT), and questionnaires assessing sleepiness, fatigue, and depression. In all, 23 patients with FMD (62%) reported excessive daytime sleepiness. Evidence of specific sleep disorders was identified in our cohort, with 35% having restless legs syndrome; 49% obstructive sleep apnea; and 8% periodic limb movements in sleep; however, the presence of these disorders was not correlated with subjective sleepiness. Patients with FMD with self-reported sleepiness reported higher fatigue (p = 0.002), depression (p = 0.002), and had longer sleep latencies in the MSLT (p < 0.001) compared to the patients with central hypersomnia. No correlation was found between subjective and objective sleepiness in either group. Fatigue positively correlated with self-reported sleepiness in patients with FMD (p < 0.001). This study did not find objective correlates of increased sleepiness in patients with FMD. While sleep abnormalities were found to be common in FMD, they were not correlated with self-reports of excessive sleepiness. Positive correlations between self-reported sleepiness and fatigue support the current unified model of non-motor symptoms in FMD.

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.

Methods for Neuroscience Drug Development: Guidance on Standardization of the Process for Defining Clinical Outcome Strategies in Clinical Trials

Neurosciences clinical trials continue to have notoriously high failure rates. Appropriate outcomes selection in early clinical trials is key to maximizing the likelihood of identifying new treatments in psychiatry and neurology. The field lacks good standards for designing outcome strategies, therefore The Outcomes Research Group was formed to develop and promote good practices in outcome selection. This article describes the first published guidance on the standardization of the process for clinical outcomes in neuroscience. A minimal step process is defined starting as early as possible, covering key activities for evidence generation in support of content validity, patient-centricity, validity requirements and considerations for regulatory acceptance. Feedback from expert members is provided, regarding the risks of shortening the process and examples supporting the recommended process are summarized. This methodology is now available to researchers in industry, academia or clinics aiming to implement consensus-based standard practices for clinical outcome selection, contributing to maximizing the efficiency of clinical research.

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.

Cortisol in functional neurological disorders: State, trait and prognostic biomarkers

OBJECTIVE

Biological stress dysregulation, such as a flattened cortisol awakening response (CAR), has been identified in functional neurological disorder (FND). This longitudinal study aimed to explore whether CAR alterations in FND serve as state or trait biomarkers, assessing temporal changes in cortisol and clinical outcomes to test its prognostic value.

METHODS

Salivary cortisol was measured in 53 patients with mixed FND at two visits separated by eight months (M0 and M8). CAR was calculated based on five consecutive samples, each taken with 15-min time intervals, collected upon awakening, whereas cortisol amplitude (CAmp) was calculated as the difference between the morning peak and the afternoon trough. Clinical outcome was assessed with the Functional Movement Disorder Rating Scale (S-FMDRS), Clinical global impression (CGI) scores for severity (CGI-S) and improvement (CGI-I) and the short-form health survey (SF-36).

RESULTS

No differences in CAR levels were found between M0 and M8 regardless of clinical outcome (remained flattened). However, a good clinical outcome was associated with an earlier peak in the CAR (p = .013, odds ratio: 1.78; 95%-confidence interval: 0.095-1.13). A higher CAmp at M0 predicted a better outcome at M8 (β = 1.14, 95%-confidence interval:0.15-2.13, p = .03).

CONCLUSION

A flattened CAR might represent a trait marker for FND, when an earlier peak in the CAR may serve as a state biomarker. The CAmp demonstrates predictive power for clinical outcome, potentially representing a prognostic biomarker for FND. Further replication and follow-up studies are essential to confirm this suggested role of cortisol as a multifaceted biomarker of FND.

Outcome of psychogenic non-epileptic seizures following diagnosis in the epilepsy monitoring unit

Objective

To study the outcome of patients with psychogenic non-epileptic seizures (PNES) after their diagnosis in the epilepsy monitoring unit (EMU).

Methods

Patients diagnosed in our EMU with definite PNES between January 2009 and May 2023 were contacted by phone, and those who agreed to participate were asked a set of predetermined questions. Comparative analyses were carried out on several variables before and after diagnosis: number of participants with daily PNES, number of visits to the emergency department, number of participants who consulted their general practitioner or a neurologist outside of a scheduled follow-up, number of participants who took antiseizure medications (ASMs) or psychotropic drugs, and employment status.

Results

Out of the 103 patients with a definite diagnosis of PNES, 61 patients (79% female) accepted to participate in our study. The median age at PNES onset was 35 years, and the median delay to diagnosis was 3 years. Almost two-thirds (62%) were receiving ASMs and 40% psychotropic drugs. The mean stay at the EMU was 5 days. PNES diagnosis was explained to almost all patients (97%) by the end of their EMU stay and was well-accepted by most (89%). When contacted, 46% of participants no longer had PNES; 32% mentioned that their PNES had ceased immediately upon communication of the diagnosis. The median follow-up duration was 51 months. Fewer patients had daily seizures after the diagnosis (18 vs. 38%; p < 0.0455). Similarly, the median number of emergency department visits was significantly lower (0 vs. 2; p < 0.001). Only 17 patients consulted their general practitioner (vs. 40, p < 0.001) and 20 a neurologist (vs. 55, p < 0.001) after a PNES attack outside of a scheduled follow-up. The use of ASMs was also significantly reduced from 70 to 33% (p < 0.01), with only one still taking an ASM for its antiseizure properties. Significantly more participants were working at last follow-up than at PNES diagnosis (49 vs. 25%; p < 0.001).

Conclusion

Our study revealed a relatively favorable long-term outcome of definite PNES diagnosed in the EMU that translated in significant reductions in PNES frequency, health care utilization and ASM use, as well as a significant increase in employment rate.

Efficacy of Hypnosis and Catalepsy Induction in Functional Neurological Disorders

BACKGROUND

Patients with Functional Neurological Disorder (FND) experience complex patterns of motor and/or sensory symptoms. Treatment studies of psychological interventions are promising but limited.

OBJECTIVES

The aim of the current pilot study is to investigate the effect of treatment consisting of a combination of hypnosis and catalepsy induction on FND symptom severity.

METHODS

A within-subject waiting list-control design was used with 46 patients diagnosed with FND. The treatment consisted of 10 sessions. The primary outcome measure was FND symptom severity (The Psychogenic Movement Disorder Rating Scale; PMDRS). The secondary outcome measures were psychological distress and quality of life.

RESULTS

The repeated measures (RM) ANOVA for the PMDRS as outcome measure revealed a significant effect for time with a large effect size (η2  = 0.679). Pairwise comparisons indicated that the effect of time in the treatment period was significant for the measure of FND symptom severity, whereas the waiting list period was not. The effect remained stable even at 8 weeks post treatment. As for the additional measurement, general psychological distress and quality of life, no statistically significant differences between individual time points were found.

CONCLUSIONS

This pilot study showed that eight sessions of treatment consisting of a combination of hypnosis and catalepsy induction was effective in reducing FND symptom severity. Some explanations and limitations are provided in the paper as well as several avenues of future research.

The central role of the Thalamus in psychosis, lessons from neurodegenerative diseases and psychedelics

The PD-DLB psychosis complex found in Parkinson's disease (PD) and Dementia with Lewy Bodies (DLB) includes hallucinations, Somatic Symptom/Functional Disorders, and delusions. These disorders exhibit similar presentation patterns and progression. Mechanisms at the root of these symptoms also share similarities with processes promoting altered states of consciousness found in Rapid Eye Movement sleep, psychiatric disorders, or the intake of psychedelic compounds. We propose that these mechanisms find a crucial driver and trigger in the dysregulated activity of high-order thalamic nuclei set in motion by ThalamoCortical Dysrhythmia (TCD). TCD generates the loss of finely tuned cortico-cortical modulations promoted by the thalamus and unleashes the aberrant activity of the Default Mode Network (DMN). TCD moves in parallel with altered thalamic filtering of external and internal information. The process produces an input overload to the cortex, thereby exacerbating DMN decoupling from task-positive networks. These phenomena alter the brain metastability, creating dreamlike, dissociative, or altered states of consciousness. In support of this hypothesis, mind-altering psychedelic drugs also modulate thalamic-cortical pathways. Understanding the pathophysiological background of these conditions provides a conceptual bridge between neurology and psychiatry, thereby helping to generate a promising and converging area of investigation and therapeutic efforts.

The Financial Burden of Functional Neurological Disorders

PURPOSE OF REVIEW

Functional neurological disorder (FND) is a common and severely debilitating condition lacking clinical ownership, existing between neurology and psychiatry. This article reports the findings of recent research investigating the economic costs of FND diagnosis and management. We define what the costs are, why they exist, and suggest actionable steps to reduce them.

RECENT FINDINGS

The financial burden of FND exists across the globe characterized by high healthcare utilization resulting in exorbitant direct and indirect costs for the patient, healthcare system, and society. Inadequate medical education and stigmatization of the disorder prolong the time to diagnosis, during which cyclical utilization of inpatient and emergency department services drive up costs. Despite being cost-effective, lack of accessible treatment compounds the issue, leaving patients without a reliable exit. Recent findings support an increased awareness and the need for a cultural shift to overcome the financial burden associated with this underserved population.

Outpatient Motor Retraining for Functional Movement Disorder: Predictors of a Favorable Short-Term Response

Background

Treating functional movement disorder (FMD) with motor retraining is effective but resource intensive.

Objectives

Identify patient, disease, and program variables associated with favorable treatment outcomes.

Methods

Retrospective review of the 1 week intensive outpatient FMD program at Mayo Clinic in Minnesota from February 2019 to August 2021. Outcomes included patient-reported measures (Canadian Occupational Performance Measure-Performance and Satisfaction subscales [COPM-P and COPM-S, range 0-10] and Global Rating of Change [GROC, -7 to +7]) and a retrospective investigator-rated scale (0-3, worse/not improved to significantly improved/resolved). Linear regression models identified variables predicting favorable outcomes.

Results

Participants (n = 201, 74% female, mean age = 46) had median FMD duration of 24 months. The commonest FMD subtypes were gait disorder (65%), tremor (41%) and weakness (17%); 53% had ≥2 subtypes. Most patients (88%) completed a therapeutic screening process before program entry. Patient-reported outcomes at the end of the week improved substantially (COPM-P average change 3.8 ± 1.9; GROC post-program average 5.5 ± 1.7). Available investigator-rated outcomes from short-term follow-up were also positive (102/122 [84%] moderately to significantly improved/resolved). Factors predicting greater improvement in COPM-P were completing therapeutic screening, higher number of non-motor symptoms, shorter FMD duration, earlier program entry, lower baseline COPM scores, and (among screened patients) higher GROC between therapeutic screening and program start.

Conclusion

Patients with diverse FMD subtypes improved substantially over a 1 week period. Utilization of therapeutic screening and greater improvement between therapeutic screening and program start were novel predictors of favorable outcomes. Non-motor symptoms did not preclude positive responses, although patients with predominant non-motor burden were excluded.

Physical Rehabilitation of Motor Functional Neurological Disorders: A Narrative Review

Functional Neurological Disorders (FNDs) are one of the most common and disabling neurological disorders, affecting approximately 10-30% of patients in neurology clinics. FNDs manifest as a range of motor, sensory, and cognitive symptoms that are not explained by organic disease. This narrative review aims to assess the current state of knowledge in physical-based rehabilitation for motor/movement FNDs in the adult population, with the goal of improving research and medical care for this patient population. To ensure optimal outcomes for patients, it is critical to consider several domains pertaining to FNDs, including which field of discipline they should belong to, how to investigate and test, methods for rating outcome measures, and optimal courses of treatment. In the past, FNDs were primarily treated with psychiatric and psychological interventions. However, recent literature supports the inclusion of physical rehabilitation in the treatment of FNDs. Specifically, physical-based approaches tailored to FNDs have shown promising results. This review utilized a comprehensive search of multiple databases and inclusion criteria to identify relevant studies.

Speech and language therapy: A treatment case series of 20 patients with functional speech disorder

BACKGROUND

While expert consensus recommendations support the use of speech and language therapy (SLT) for patients with functional speech disorder (FND-speech), there are limited published data on clinical outcomes.

OBJECTIVE

To retrospectively report the treatment outcomes and clinical characteristics of patients with FND-speech that attended outpatient SLT as part of a multidisciplinary program for functional neurological disorder (FND).

METHODS

In this case series, we included adult patients with FND-speech that consecutively participated in outpatient SLT at our institution between October 2014 and September 2021. Baseline demographic and neuropsychiatric characteristics were extracted from the medical records, along with data on FND-speech phenotypes, number of treatment sessions received, and clinician-determined outcomes. Only descriptive statistics were used to report findings.

RESULTS

Twenty patients met inclusion criteria; ages ranged from 21-77, with a mean of 51.6±16.2 years. 85% of the cohort presented with mixed FND-speech symptoms. Patients attended a range of 2-37 visits, with an average of 9.2±8.0 visits over 4.4±3.5 months. At the last treatment session, 3 patients were asymptomatic, 15 had improved, and 2 had not improved; 8 individuals that improved received video telehealth interventions.

CONCLUSION

This case series lends additional support for outpatient SLT in the assessment and management of individuals with FND-speech, and may help clarify patient and provider treatment expectations. Additional prospective research is needed to investigate baseline predictors of treatment response and further define the optimal frequency, intensity, duration, and clinical setting for SLT delivery in this population.

Diagnosis and Management of Functional Tic-Like Phenomena

Over the past 3 years, a global phenomenon has emerged characterized by the sudden onset and frequently rapid escalation of tics and tic-like movements and phonations. These symptoms have occurred not only in youth known to have tics or Tourette syndrome (TS), but also, and more notably, in youth with no prior history of tics. The Tourette Association of America (TAA) convened an international, multidisciplinary working group to better understand this apparent presentation of functional neurological disorder (FND) and its relationship to TS. Here, we review and summarize the literature relevant to distinguish the two, with recommendations to clinicians for diagnosis and management. Finally, we highlight areas for future emphasis and research.

Compassion-Focused Therapy for an Older Adult with Motor Functional Neurological Disorder: A Case Study

OBJECTIVES

Motor functional neurological disorder (mFND) is a condition where individuals may experience difficulties such as tremors, gait impairments, and paralysis which are not explained by identified structural damage to the brain. Studies on chronic conditions have suggested that psychological interventions such as compassion-focused therapy (CFT) may be effective in improving well-being in people with mFND. However, no evidence is currently available on psychotherapy for older people with mFND.

METHODS

A 12-session CFT intervention was delivered to an 81-year-old British male with mFND. Standardized measures were administered at baseline and post-intervention.

RESULTS

At post-intervention, a 30% decrease in perceived psychological impact of mFND was found, along with clinically significant changes in anxiety and depression. Good levels of feasibility and acceptability were also observed.

CONCLUSIONS

To our knowledge, this is the first evidence of the feasibility, acceptability, and potential effectiveness of CFT for psychological difficulties linked with mFND, as well as the first evidence for any psychotherapy with an older adult with mFND.

CLINICAL IMPLICATIONS

CFT shows the potential to be effective, feasible, and acceptable for treating difficulties linked with mFND in older people. However, further high-quality investigations based on experimental designs are needed to build on the present preliminary findings.

Do demographic and clinical features and comorbidities affect the risk of spread to an additional body site in functional motor disorders?

The aim of this study is to assess changes in the body distribution and the semeiology of functional motor disorder (FMD) in patients who reported only one or more than one body site affected at FMD onset. Data were obtained from the Italian Registry of Functional Motor Disorders, which included patients with a diagnosis of clinically definite FMDs. The relationship between FMD features and spread to other body sites was estimated by multivariate Cox regression analysis. We identified 201 (49%) patients who reported only one body site affected at FMD onset and 209 (51%) who reported multiple body sites affected at onset. FMD spread from the initial site to another site in 43/201 (21.4%) patients over 5.7 ± 7.1 years in those with only one site affected at FMD onset; FMD spread to an another body site in 29/209 (13.8%) over 5.5 ± 6.5 years. The spread of FMD was associated with non-motor functional symptoms and psychiatric comorbidities only in the patients with one body site affected at FMD onset. Our findings provide novel insight into the natural history of FMD. The number of body sites affected at onset does not seem to have a consistent influence on the risk of spread. Furthermore, our findings suggest that psychiatric comorbidities and non-motor functional symptoms may predict the spread of FMD symptoms, at least in patients with one body site affected at onset.

Updates in Functional Movement Disorders: from Pathophysiology to Treatment Advances

Purpose of Review

This review discusses advances in functional movement disorders (FMD) over the past 3 years, with a focus on risk factors, diagnosis, pathophysiology, neuroimaging studies, and treatment.

Recent Findings

The past decade has brought a revived interest in functional movement disorders, with a growing number of studies exploring pathophysiological mechanisms. Here, we review recent studies demonstrating changes in attention, emotional and sensorimotor function in FMD. Through international collaborative efforts, progress has been made in defining biomarkers and outcome measures, an important prerequisite towards standardization of diagnosis and reporting of outcomes in clinical trials. Of particular interest are neuroimaging studies demonstrating functional and structural changes in motor and emotional brain circuits, deepening our understanding of FMD as a neurocircuit disorder and potentially paving the way towards new treatments. Currently available treatment modalities have shown successful outcomes via outpatient, inpatient, and virtual delivery.

Summary

The last 3 years have seen tremendous efforts to better understand, diagnose, and treat FMD. The disease model has been broadened to include a biopsychosocial formulation, and insights on the pathophysiology on FMD are informing treatment efforts. Several international multidisciplinary research collaborations are underway to define biomarkers and best outcome measures, highlighting the path towards improved standardization of future treatment trials. Additionally, the rise of telemedicine during the COVID-19 pandemic has reduced geographic barriers and paved the way for virtual therapy sessions and self-guided programs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11910-022-01192-9.

The INVEST trial: a randomised feasibility trial of psychologically informed vestibular rehabilitation versus current gold standard physiotherapy for people with Persistent Postural Perceptual Dizziness

Background

Persistent postural perceptual dizziness (PPPD) is a common and disabling functional neuro-vestibular disorder. We aimed to determine the feasibility and acceptability of conducting a randomised controlled trial of cognitive-behavioural therapy informed vestibular rehabilitation (INVEST intervention) designed for persistent dizziness.

Methods

A two-armed parallel groups randomised feasibility study of INVEST vs. a time-matched gold standard vestibular rehabilitation (VRT) control. Participants with PPPD were recruited from a specialist vestibular clinic in London, UK. Participants were individually randomised using a minimisation procedure with allocation concealment. Measures of feasibility and clinical outcome were collected and assessed at 4 months.

Results

Forty adults with PPPD were randomised to six sessions of INVEST (n = 20) or gold standard VRT (n = 20). Overall, 59% of patients screened met the inclusion criteria, of which 80% enrolled. Acceptability of INVEST, as assessed against the theoretical framework of acceptability (TFA), was excellent and 80% adhered to all 6 sessions. There were small to moderate treatment effects in favour of INVEST across all measures, including dizziness handicap, negative illness perceptions, symptom focussing, fear avoidance, and distress (standardised mean difference [SMD]_g = 0.45; SMD_g = 0.77; SMD_g = 0.56; SMD_g = 0.50, respectively). No intervention-related serious adverse events were reported.

Conclusions

The study results give strong support for the feasibility of a full-scale trial. Both arms had high rates of recruitment, retention, and acceptability. There was promising support of the benefits of integrated cognitive-behavioural therapy-based vestibular rehabilitation compared to gold standard vestibular rehabilitation. The study fulfilled all the a-priori criteria to advance to a full-scale efficacy trial.

Trial registration number

ISRCTN10420559.

Development of an inpatient rehabilitation pathway for motor functional neurological disorders: Initial reflections

BACKGROUND: Emerging research supports a primary role for rehabilitation therapy alongside psychoeducation and psychotherapy in the treatment of functional neurological disorder (FND). OBJECTIVE: While consensus recommendations for physical therapists, occupational therapists, and speech and language pathologists treating FND have been published, specific recommendations for multidisciplinary FND care delivered on an inpatient rehabilitation unit are yet to be established. METHODS: This report describes one inpatient rehabilitation facility’s efforts to design and implement a clinical pathway for patients with acute-onset motor FND—patients recently hospitalized for work-up of new neurological symptoms subsequently deemed functional. RESULTS: Detailed descriptions on defining admission criteria and delivering consensus- and evidence-based multidisciplinary inpatient rehabilitation are provided. CONCLUSIONS: In the context of prospective research studies, considerably more work is needed to delineate the optimal duration and intensity of inpatient rehabilitation treatment for the management of patients with motor FND.

The use of rhythmic auditory stimulation for functional gait disorder: A case report

BACKGROUND: Functional gait disorders (FGD) are a common and disabling condition. Consensus-based rehabilitation techniques for treating FGD and other functional neurological disorder presentations at large utilize a variety of therapeutic strategies, including distraction, novel approaches to movement, entrainment, stress/hypervigilance modulation, and psychotherapy. CASE REPORT: Here we present a case of a 24-year-old woman with a complex history of anxiety, depression, left frontal astrocytoma, postural orthostatic tachycardia syndrome (POTS) and FGD. During a multidisciplinary inpatient rehabilitation stay for FGD, the patient underwent rhythmic auditory stimulation (RAS) delivered by a neurologic music therapist in conjunction with physical therapy, occupational therapy, and psychotherapy. RESULTS: The RAS intervention appeared to play a significant role in symptom resolution for this patient. Improvement in the patient’s truncal displacement, foot dragging, and well as overall gait speed occurred following serial RAS trials performed over a single treatment session. Benefits persisted immediately following the intervention and upon subsequent reassessment. Although at four-year follow-up the patient’s FGD symptoms remained resolved, fatigue continued to limit her ambulatory capacity and overall endurance. CONCLUSION: RAS represents a unique therapeutic approach for treating FGD, complementary to existing consensus-based rehabilitation recommendations, and may warrant further consideration by the field.

Repetitive transcranial magnetic stimulation for patients with functional paralysis: a randomized controlled study

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has been proposed to treat functional neurological disorders. Here, we aim to assess the efficacy of rTMS to treat functional paralysis in a controlled randomized trial.

METHODS

Patients received 2 sessions of active or sham 0.25 Hz rTMS (60 stimuli each), with a one-day interval, applied over the motor cortex contralateral to the paralysis. The primary outcome was the number of patients with an increase in motor score between baseline and after the second rTMS session, rated by two investigators blinded to the treatment allocation. Secondary outcomes were changes in global and fine motor scores between groups after rTMS, and occurrence of adverse events.

RESULTS

Sixty-two patients (46 female; mean [SD] age, 35.2 [13.9] years) were enrolled and randomized. Thirteen out of 32 (41%) and 11/30 (37%) patients had increased motor strength after active or sham rTMS, respectively (p=0.80). Changes in both global and fine motor scores after rTMS relative to baseline were also not significantly different between treatment groups (median difference in the global motor score 0.62 [0.83] and 0.37 [0.61], and fine motor scores 0.12 [0.18] and 0.08 [0.11], in active and sham rTMS groups, respectively, p=0.14). We observed six serious adverse events, consisting of 3 cephalalgia in the active group and 2 cephalalgia and 1 asthenia in the sham group.

CONCLUSIONS

Two sessions of sham or active low frequency rTMS were effective to improve functional paralysis, suggesting a placebo effect of this non-invasive brain stimulation technique.

Diagnosis and management of functional neurological disorder

Functional neurological disorder (FND), previously regarded as a diagnosis of exclusion, is now a rule-in diagnosis with available treatments. This represents a major step toward destigmatizing the disorder, which was often doubted and deemed untreatable. FND is prevalent, generally affecting young and middle aged adults, and can cause severe disability in some individuals. An early diagnosis, with subsequent access to evidence based rehabilitative and/or psychological treatments, can promote recovery-albeit not all patients respond to currently available treatments. This review presents the latest advances in the use of validated rule-in examination signs to guide diagnosis, and the range of therapeutic approaches available to care for patients with FND. The article focuses on the two most frequently identified subtypes of FND: motor (weakness and/or movement disorders) and seizure type symptoms. Twenty two studies on motor and 27 studies on seizure type symptoms report high specificities of clinical signs (64-100%), and individual signs are reviewed. Rehabilitative interventions (physical and occupational therapy) are treatments of choice for functional motor symptoms, while psychotherapy is an emerging evidence based treatment across FND subtypes. The literature to date highlights heterogeneity in responses to treatment, underscoring that more research is needed to individualize treatments and develop novel interventions.

In Patients With Functional Movement Disorders, Is Specialized Physical Therapy Effective in Improving Motor Symptoms?: A Critically Appraised Topic

BACKGROUND

Functional movement disorders (FMD, aka psychogenic movement disorders) are very common and frequently chronic and disabling. Despite this, there is a paucity of evidence-based treatment to manage and alleviate these conditions. Specialized physical therapy (PT), involving sequential motor relearning and redirecting attention, has shown promise as a therapeutic intervention for motor symptoms.

METHODS

The objective of this study was to critically assess current evidence regarding specialized PT compared with usual care in improving motor symptoms among patients with FMD. This was addressed through the development of a structured critically appraised topic. This included a clinical scenario with a clinical question, literature search strategy, critical appraisal, results, evidence summary, commentary, and bottom-line conclusions. Participants included consultant and resident neurologists, a medical librarian, and content experts in the fields of physical medicine and rehabilitation, physical and occupational therapy, psychiatry, and psychology.

RESULTS

A randomized controlled feasibility trial was identified and selected for critical appraisal. This study randomized 60 patients with FMD to a 5-day specialized outpatient PT program or to general outpatient PT referral, and measured patient-reported and clinician-measured outcomes. At 6 months, 72% of patients in the intervention group had a good outcome compared with 18% of control group patients. Patients in the specialized outpatient PT program had significantly better outcomes in 3 Short-Form 36 (SF36) domains (d=0.46 to 0.79) and multiple other scales of physical and social function as well as clinician-measured outcomes. The intervention resulted in 0.08 additional quality-adjusted life years in a cost-effective manner.

CONCLUSIONS

Current evidence suggests that in patients with FMD, specialized PT improves motor symptoms in a clinically significant, sustained, and cost-effective manner. This promising intervention warrants further investigation and replication.

Management of Functional Neurological Disorders (FND): Experience from a Swiss FND Clinic

Functional neurological disorder (FND) represent a common disorder with significant socio-economic impact. In this context and alongside recent new neuroscientific insights, FND attracts a growing interest both in clinical practice and academic activities. New international recommendation and expert opinions suggest that therapy of FND should be a tailored multidisciplinary management involving the neurologist, the physiotherapist, and in most cases the psychotherapist/psychiatrist. A first decisive step is the establishment of a definitive diagnosis, based on the presence of clinical positive signs during neurological assessment together with a clear communication and explanation of the diagnosis by the neurologist. A second important step is based on individual therapeutic sessions, involving different disciplines (neurology and psychotherapy or neurology and physiotherapy). Comorbidities, such as pain or fatigue and psychiatric comorbidities (anxiety, depression, dissociation etc.) should be carefully evaluated, as they need an individualized treatment path. New FND clinics have been created worldwide over the last decades to offer such multidisciplinary settings and this article will present the experience of a first Swiss FND clinic created in 2016. The aim is to highlight in the form of a narrative review the current literature supporting the usefulness and importance of FND clinics, by reviewing the latest evidence on multidisciplinary interventions in FND.

Functional neurological symptom disorder: Preliminary findings of factors associated with walking ability post integrative pediatric rehabilitation

PURPOSE

The current study's aims were to (1) examine long-distance walking ability (6-minute walking test [6MWT]) and walking hemodynamic responses (i.e., heart rate) among youth with functional neurological symptom disorder (FNSD) before and after an integrative pediatric rehabilitation (IPR) program; and (2) explore factors predicting improvement in walking ability.

METHODS

Thirty-one youth with FNSD participating in an IPR program were recruited. The IPR program was activated biweekly in an ambulatory format. Study measures included the 6MWT, hemodynamic characteristics, rate of perceived exertion (RPE), pain-intensity perception, and Child's Somatization Inventory-24 (CSI-24). All measures were conducted upon admission to the IPR and discharge.

RESULTS

Findings indicated a significant increase in 6MWT distance, as well as decreases in heart rate, RPE, and pain-intensity perception from admission to discharge. At admission, CSI-24 and pain intensity predicted 6MWT distance (adjusted R2 = 0.68). Pain intensity predicted discharge 6MWT distance (adjusted R2 = 0.18). Initial 6MWT predicted changes in 6MWT distance from admission to discharge (adjusted R2 = 0.33).

CONCLUSION

Using an integrative rehabilitation approach increases walking distance and decreases pain-related symptoms in youth with FNSD, emphasizing the need for collaboration between physical therapists and pediatric psychologists. Moreover, changes in walking ability may increase participation and thus should be the focus of IPR.

Toward a possible trauma subtype of functional neurological disorder: Impact on symptom severity and physical health

BACKGROUND

As a group, individuals with functional neurological disorder (FND) report an approximately 3-fold increase in adverse life experiences (ALEs) compared to healthy controls. In patients with FND, studies have identified a positive correlation between symptom severity and the magnitude of ALEs. While not all individuals with FND report ALEs, such findings raise the possibility of a trauma-subtype of FND.

OBJECTIVE

This study investigated if patients with FND, with or without probable post-traumatic stress disorder (PTSD) and/or significant childhood maltreatment, differed in their symptom severity and physical health.

MATERIALS AND METHODS

Seventy-eight patients with FND were recruited (functional seizures, n = 34; functional movement disorder, n = 56). Participants completed self-report measures of symptom severity [Somatoform Dissociation Questionniare-20 (SDQ-20), Screening for Somatoform Disorders: Conversion Disorder subscale (SOMS:CD), Patient Health Questionniare-15 (PHQ-15)], physical health [Short Form Health Survey-36 (SF36-physical health)], childhood maltreatment [Childhood Trauma Questionnaire (CTQ)], and PTSD [PTSD Checklist-5 (PCL-5)]; a psychometric battery of other common predisposing vulnerabilities was also completed. To adjust for multiple comparisons, a Bonferroni correction was applied to all univariate analyses.

RESULTS

Patients with FND and probable PTSD (n = 33) vs. those without probable PTSD (n = 43) had statistically significant increased scores on all symptom severity measures - as well as decreased physical health scores. In secondary post-hoc regression analyses, these findings remained significant adjusting for age, sex, race, college education, and: pathological dissociation; alexithymia; attachment styles; personality characteristics; resilience scores; functional seizures subtype; or moderate-to-severe childhood abuse and neglect scores; SOMS:CD and SDQ-20 findings also held adjusting for depression and anxiety scores. In a separate set of analyses, patients with FND and moderate-to-severe childhood abuse (n = 46) vs. those without moderate-to-severe childhood abuse (n = 32) showed statistically significant increased SDQ-20 and PHQ-15 scores; in post-hoc regressions, these findings held adjusting for demographic and other variables. Stratification by childhood neglect did not relate to symptom severity or physical health scores.

CONCLUSION

This study provides support for a possible trauma-subtype of FND. Future research should investigate the neurobiological and treatment relevance of a FND trauma-subtype, as well as continuing to delineate clinical characteristics and mechanisms in individuals with FND that lack a history of ALEs.

[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.

Neurostimulation for the treatment of functional neurological disorder: A systematic review

Functional Neurological Disorder (FND), also known as conversion disorder, is characterized by neurological symptoms that are incompatible with any known structural disorder and best explained by a biopsychosocial model. Evidence-based treatments for FND are limited, with cognitive behavioral therapy (CBT) and physiotherapy being the most effective interventions [1]. In recent years, functional neuroimaging studies have provided robust evidence of alterations in activity and connectivity in multiple brain networks in FND. This body of evidence suggests that neurocircuitry-based interventions, such as non-invasive brain stimulation techniques (NIBS), may also represent an effective therapeutic option for patients with FND. In this systematic review, we outline the current state of knowledge of NIBS in FND, and discuss limitations and future directions that may help establish the efficacy of NIBS as a therapeutic option for FND.

Subjective versus objective measures of distress, arousal and symptom burden in patients with functional seizures and other functional neurological symptom disorder presentations: A systematic review

Symptoms and functioning can be measured subjectively using self-report measures or objectively, based on physiological changes. This raises the question whether subjective and objective measures are closely correlated and - if not - whether one is more accurate or meaningful than the other, especially in patients with Functional Seizures (FS) or other Functional Neurological Symptom Disorders (FND), where subjective and objective observations may be thought particularly likely to deviate. This systematic review explores these questions focussing on measures of distress, arousal and symptom burden. Eighteen studies (12 FS, 6 other FND) capturing 396 FND patients were included. Eleven reported no correlation between subjective and objective measures. Only four studies reported significant correlations (r's = -0.74-0.59, p's < 0.05). The small number of studies and diverse methodologies do not provide conclusive answers to the questions posed. Given that subjective and objective measures capture different aspects of current state or function, a combination of measurement approaches is likely to provide optimal information about patients' health state. In view of the attentional and perceptual alterations implicated in FND, the difference between objective and subjective measures may represent an interesting observation in its own right.

A Review and Expert Opinion on the Neuropsychiatric Assessment of Motor Functional Neurological Disorders

Functional neurological (conversion) disorder (FND) is a prevalent and disabling condition at the intersection of neurology and psychiatry. Advances have been made in elucidating an emerging pathophysiology for motor FND, as well as in identifying evidenced-based physiotherapy and psychotherapy treatments. Despite these gains, important elements of the initial neuropsychiatric assessment of functional movement disorders (FND-movt) and functional limb weakness/paresis (FND-par) have yet to be established. This is an important gap from both diagnostic and treatment planning perspectives. In this article, the authors performed a narrative review to characterize clinically relevant variables across FND-movt and FND-par cohorts, including time course and symptom evolution, precipitating factors, medical and family histories, psychiatric comorbidities, psychosocial factors, physical examination signs, and adjunctive diagnostic tests. Thereafter, the authors propose a preliminary set of clinical content that should be assessed during early-phase patient encounters, in addition to identifying physical signs informing diagnosis and potential use of adjunctive tests for challenging cases. Although clinical history should not be used to make a FND diagnosis, characteristics such as acute onset, precipitating events (e.g., injury and surgery), and a waxing and waning course (including spontaneous remissions) are commonly reported. Active psychiatric symptoms (e.g., depression and anxiety) and ongoing psychosocial stressors also warrant evaluation. Positive physical examination signs (e.g., Hoover's sign and tremor entrainment) are key findings, as one of the DSM-5 diagnostic criteria. The neuropsychiatric assessment proposed emphasizes diagnosing FND by using "rule-in" physical signs while also considering psychiatric and psychosocial factors to aid in the development of a patient-centered treatment plan.

Shared Individual Formulation Therapy (SIFT): an open-label trial of a new therapy accommodating patient heterogeneity in functional neurological disorder

BACKGROUND

Functional Neurological Disorder (FND) is a complex neuropsychiatric condition with a multifactorial aetiology. The heterogeneity of patients with FND is rarely considered in psychotherapy trials, which may contribute to variable outcomes. Shared Individual Formulation Therapy (SIFT) is a new, brief (four session) psychotherapy that aims to accommodate heterogeneity by providing a personalised, trans-theoretical formulation of the person's difficulties and accompanying management plan.

METHODS

An open-label, prospective trial of outpatient SIFT for adults with FND was conducted, using health-related quality of life (SF-12) as the principal outcome measure, with secondary measures of mental health, dissociation, health care use and attitude to the FND diagnosis. Measures were collected at baseline, end of treatment and 6- and 12-month follow-ups.

RESULTS

Twenty-nine participants with various FND symptoms enrolled. Twenty-four completed all four sessions and 25 completed follow-up measures at 12 months. SF-12 scores improved significantly at end of treatment and were sustained throughout follow-up with moderate effect sizes (0.39-0.47; all p < 0.001). Most secondary outcomes also improved significantly at all time points. The intervention was highly acceptable and tolerable to patients and perceived as beneficial.

CONCLUSION

This trial provides preliminary evidence for initial and sustained benefit from SIFT for adults with FND. Further study is needed to validate these findings.

International online survey of 1048 individuals with functional neurological disorder

BACKGROUND AND PURPOSE

Functional neurological disorder (FND) is common, and symptoms can be severe. There have been no international large-scale studies of patient experiences of FND.

METHODS

A patient questionnaire was created to assess FND patient characteristics, symptom comorbidities and illness perceptions. Respondents were recruited internationally through an open access questionnaire via social media and patient groups over a month-long period.

RESULTS

In total, 1048 respondents from 16 countries participated. Mean age was 42 years (86% female). Median FND symptom duration was 5 years, and median time from first symptom to diagnosis was 2 years. Mean number of current symptoms (core FND and associated) was 9.9. Many respondents had associated symptoms, for example fatigue (93%), memory difficulties (80%) and headache (70%). Self-reported psychiatric comorbidities were relatively common (depression, 43%; anxiety, 51%; panic, 20%; and post-traumatic stress disorder, 22%). Most respondents reported that FND had multiple causes, including physical and psychological.

CONCLUSIONS

This large survey adds further evidence that people with FND typically have high levels of multiple symptom comorbidity with resultant distress. It also supports the notion that associated physical symptoms are of particular clinical significance in FND patients. Dualistic ideas of FND were not supported by respondents, who generally preferred to conceptualize the disorder as one at the interface of mind and brain. The need for a broad approach to this poorly served patient group is highlighted. Potential selection and response biases due to distribution of the survey online, mostly via FND patient groups, are a key limitation.

A Service Evaluation of the Experiences of Patients With Functional Neurological Disorders Within the NHS

Previous research into Functional Neurological Disorder (FND) has shown that there are significant barriers in providing patient-centred care. However, there has been no specific research into whether patient experiences of care for FND meet the current standards of care. This study aimed to investigate the types of problems experienced by FND patients, and whether these differed to patients with multiple sclerosis (MS). FND (n = 40) and MS patients (n = 37) were recruited from NHS tertiary neurology clinics and completed questionnaires on their experiences of health care services. Significant differences in experiences of care between the two patient groups were found, with FND patients reporting significantly more problems in their diagnosis and treatment (p = 0.003), patient-centred care (p < 0.001), relationships with healthcare professionals (p < 0.001), and in accessing community care (p = 0.001). Limitations include a small sample size, specificity to a single centre, and cross-sectional design. The results suggest that current care for FND patients is not meeting expected standards for long-term neurological conditions, highlighting the need for structured care pathways and patient-centred care.

Functional Neurologic Disorders: The Need for a Model of Care

Neurologists are commonly consulted for patients with a functional neurologic disorder. Best practices as to their diagnosis and treatment have been established, and multiple academic centers have programs in place for their treatment. However, given the number of patients suffering from this condition, a comprehensive model of care that can be broadly implemented needs to be developed and applied beyond specialized academic programs.

Neuroimaging in Functional Neurological Disorder: State of the Field and Research Agenda

Functional neurological disorder (FND) was of great interest to early clinical neuroscience leaders. During the 20th century, neurology and psychiatry grew apart - leaving FND a borderland condition. Fortunately, a renaissance has occurred in the last two decades, fostered by increased recognition that FND is prevalent and diagnosed using "rule-in" examination signs. The parallel use of scientific tools to bridge brain structure - function relationships has helped refine an integrated biopsychosocial framework through which to conceptualize FND. In particular, a growing number of quality neuroimaging studies using a variety of methodologies have shed light on the emerging pathophysiology of FND. This renewed scientific interest has occurred in parallel with enhanced interdisciplinary collaborations, as illustrated by new care models combining psychological and physical therapies and the creation of a new multidisciplinary FND society supporting knowledge dissemination in the field. Within this context, this article summarizes the output of the first International FND Neuroimaging Workgroup meeting, held virtually, on June 17th, 2020 to appraise the state of neuroimaging research in the field and to catalyze large-scale collaborations. We first briefly summarize neural circuit models of FND, and then detail the research approaches used to date in FND within core content areas: cohort characterization; control group considerations; task-based functional neuroimaging; resting-state networks; structural neuroimaging; biomarkers of symptom severity and risk of illness; and predictors of treatment response and prognosis. Lastly, we outline a neuroimaging-focused research agenda to elucidate the pathophysiology of FND and aid the development of novel biologically and psychologically-informed treatments.

Emotion Induced Monoamine Neuromodulator Release Affects Functional Neurological Disorders

Functional neurologic disorders (FNDs), also called conversion disorder (previously called hysteria), can show almost all the symptoms of other neurological diseases, including both physical (for example, seizure, weakness, fatigue) and psychological (for instance, depression, anxiety) symptoms. In spite of our general knowledge about emotional processes and developmental defects in the formation of these somatic symptoms, there is still no systemic and comprehensive research on the effects of emotional developmental variables in FND. Recently, both experimental and theoretical emotion studies have been greatly increased, such as prediction error, conceptual act model, basic emotional theory, and monoamine neuromodulator based three primary emotions. In addition, a large amount of evidence has confirmed the role of psychosocial adversity (such as stressful life events, interpersonal difficulties) as an important risk factor for FND. Here, we review recent advances about emotional stress on FND, and pay special attention to the effects of monoamine neuromodulators, such as how norepinephrine and serotonin affect behaviors. Then, we discuss the significance of these changes for FND, which may contribute to clarifying the pathogenesis of FND, and thus provide potential therapeutic drug targets or psychological intervention methods in the future.

Changes of Phenotypic Pattern in Functional Movement Disorders: A Prospective Cohort Study

Introduction: Functional movement disorders (FMD) refer to a group of movement disorders that present with clinical characteristics incongruent to those due to established pathophysiologic processes, as for example in the case of neurodegeneration or lesions. The aim of this study was to assess clinical features that contribute to the specific phenotypic presentations and disease course of FMD. Methods: The study consisted of 100 patients with FMD treated at Clinic for Neurology, Clinical Center of Serbia, who were longitudinally observed. Comprehensive clinical and psychiatric assessment was performed at the baseline, when initial FMD phenotype was defined. Follow-up assessment of phenotypic pattern over the time and clinical course was done after 3.2 ± 2.5 years at average. Results: We showed that 48% of FMD patients were prone to changes of phenotypic pattern during the disease course. Dystonia had tendency to remains as single and unchanged phenotype over the time (68.2%), while patients initially presented with Tremor, Gait disorder, Parkinsonism and Mixed phenotype were more susceptible to developing additional symptoms (62.5, 50, and 100%, respectively). Higher levels of somatoform experiences (p = 0.033, Exp(B) = 1.082) and higher motor severity (p = 0.040, Exp(B) = 1.082) at baseline assessment were associated with an increased likelihood of further enriching of FMD phenotype with additional functional symptoms. Also, these patients more frequently reported pain, and had higher scores on majority of applied psychiatric scales, together with more frequent presence of major depressive disorder. Conclusion: Results from this prospective study suggested tendency for progression and enrichment of functional symptoms in FMD patients over time. Besides functional core symptoms, other key psychological and physical features (like pain or multiple somatisations) were quite relevant for chronicity and significant dysability of FMD patients.

Trial Of Neurostimulation In Conversion Symptoms (TONICS): a feasibility randomised controlled trial of transcranial magnetic stimulation for functional limb weakness

OBJECTIVES

Transcranial magnetic stimulation (TMS) has been used therapeutically for functional (conversion) motor symptoms but there is limited evidence for its efficacy and the optimal protocol. We examined the feasibility of a novel randomised controlled trial (RCT) protocol of TMS to treat functional limb weakness.

DESIGN

A double-blind (patient, outcome assessor) two parallel-arm, controlled RCT.

SETTING

Specialist neurology and neuropsychiatry services at a large National Health Service Foundation Trust in London, UK.

PARTICIPANTS

Patients with a diagnosis of functional limb weakness (Diagnostic and Statistical Manual of Mental Disorders - Fifth Edition). Exclusion criteria included comorbid neurological or major psychiatric disorder, contraindications to TMS or previous TMS treatment.

INTERVENTIONS

Patients were randomised to receive either active (single-pulse TMS to primary motor cortex (M1) above resting motor threshold) or inactive treatment (single-pulse TMS to M1 below resting motor threshold). Both groups received two TMS sessions, 4 weeks apart.

OUTCOME MEASURES

We assessed recruitment, randomisation and retention rates. The primary outcome was patient-rated symptom change (Clinical Global Impression-Improvement scale, CGI-I). Secondary outcomes included clinician-rated symptom change, psychosocial functioning and disability. Outcomes were assessed at baseline, both TMS visits and at 3-month follow-up.

RESULTS

Twenty-two patients were recruited and 21 (96%) were successfully randomised (active=10; inactive=11). Nineteen (91%) patients were included at follow-up (active=9; inactive=10). Completion rates for most outcomes were good (80%-100%). Most patients were satisfied/very satisfied with the trial in both groups, although ratings were higher in the inactive arm (active=60%, inactive=92%). Adverse events were not more common for the active treatment. Treatment effect sizes for patient-rated CGI-I scores were small-moderate (Cliff's delta=-0.1-0.3, CIs-0.79 to 0.28), reflecting a more positive outcome for the active treatment (67% and 44% of active arm-rated symptoms as 'much improved' at session 2 and follow-up, respectively, vs 20% inactive group). Effect sizes for secondary outcomes were variable.

CONCLUSIONS

Our protocol is feasible. The findings suggest that supramotor threshold TMS of M1 is safe, acceptable and potentially beneficial as a treatment for functional limb weakness. A larger RCT is warranted.

TRIAL REGISTRATION NUMBER

ISRCTN51225587.

Occupational therapy consensus recommendations for functional neurological disorder

BACKGROUND

People with functional neurological disorder (FND) are commonly seen by occupational therapists; however, there are limited descriptions in the literature about the type of interventions that are likely to be helpful. This document aims to address this issue by providing consensus recommendations for occupational therapy assessment and intervention.

METHODS

The recommendations were developed in four stages. Stage 1: an invitation was sent to occupational therapists with expertise in FND in different countries to complete two surveys exploring their opinions regarding best practice for assessment and interventions for FND. Stage 2: a face-to-face meeting of multidisciplinary clinical experts in FND discussed and debated the data from stage 1, aiming to achieve consensus on each issue. Stage 3: recommendations based on the meeting were drafted. Stage 4: successive drafts of recommendations were circulated among the multidisciplinary group until consensus was achieved.

RESULTS

We recommend that occupational therapy treatment for FND is based on a biopsychosocial aetiological framework. Education, rehabilitation within functional activity and the use of taught self-management strategies are central to occupational therapy intervention for FND. Several aspects of occupational therapy for FND are distinct from therapy for other neurological conditions. Examples to illustrate the recommendations are included within this document.

CONCLUSIONS

Occupational therapists have an integral role in the multidisciplinary management of people with FND. This document forms a starting point for research aiming to develop evidence-based occupational therapy interventions for people with FND.

Towards an Outpatient Model of Care for Motor Functional Neurological Disorders: A Neuropsychiatric Perspective

Functional neurological disorder (FND), a condition at the intersection of neurology and psychiatry, is a common and disabling outpatient referral to neurology and neuropsychiatry clinics. In this perspective article, we focus on the motor spectrum of FND (mFND), including individuals with functional movement disorders (FND-movt), functional limb weakness/paresis (FND-par) and functional [psychogenic non-epileptic/dissociative] seizures (FND-seiz). Over the past several decades, there have been dedicated efforts within the neurologic and psychiatric communities to create "rule-in" diagnostic criteria, as well as thoughtful approaches to the clinical interview, delivery of the diagnosis and the development of a patient-centered treatment plan. These advances allow the promotion of good clinical practices in the outpatient assessment and management of mFND. Informed by the literature and our prior clinical experiences, we provide suggestions on how to evaluate individuals with suspected functional motor symptoms - including conducting sensitive psychiatric and psychosocial screenings. Additional sections discuss common "rule-in" neurological examination and semiologic signs of motor FND, as well as approaches to deliver the diagnosis and formulate a treatment plan based on individual patient needs. To aid the development of shared (partially overlapping) expertise that catalyzes an interdisciplinary approach to mFND, the use of physiotherapy for therapeutic motor retraining and cognitive behavioral therapy to examine relationships between symptoms, thoughts, behaviors and emotions are also discussed. Additional clinical research is needed to further refine and operationalize the assessment and management of mFND, across clinics, healthcare settings and countries.

The chronnectome as a model for Charcot's 'dynamic lesion' in functional movement disorders

This exploratory study set out to investigate dynamic functional connectivity (dFC) in patients with jerky and tremulous functional movement disorders (JT-FMD). The focus in this work is on dynamic brain states, which represent distinct dFC patterns that reoccur in time and across subjects. Resting-state fMRI data were collected from 17 patients with JT-FMD and 17 healthy controls (HC). Symptom severity was measured using the Clinical Global Impression-Severity scale. Depression and anxiety were measured using the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI), respectively. Independent component analysis was used to extract functional brain components. After computing dFC, dynamic brain states were determined for every subject using k-means clustering. Compared to HC, patients with JT-FMD spent more time in a state that was characterized predominantly by increasing medial prefrontal, and decreasing posterior midline connectivity over time. They also tended to visit this state more frequently. In addition, patients with JT-FMD transitioned significantly more often between different states compared to HC, and incorporated a state with decreasing medial prefrontal, and increasing posterior midline connectivity in their attractor, i.e., the cyclic patterns of state transitions. Altogether, this is the first study that demonstrates altered functional brain network dynamics in JT-FMD that may support concepts of increased self-reflective processes and impaired sense of agency as driving factors in FMD.