Impact of psychogenic movement disorders versus Parkinson's on disability, quality of life, and psychopathology

Experimental evidence for a robust, transdiagnostic marker in functional disorders: Erroneous sensorimotor processing in functional dizziness and functional movement disorder

OBJECTIVE

Recent neuroscientific models suggest that functional bodily symptoms can be attributed to perceptual dysregulation in the central nervous system. Evidence for this hypothesis comes from patients with functional dizziness, who exhibit marked sensorimotor processing deficits during eye-head movement planning and execution. Similar findings in eye-head movement planning in patients with irritable bowel syndrome confirmed that these sensorimotor processing deficits represent a shared, transdiagnostic mechanism. We now examine whether erroneous sensorimotor processing is also at play in functional movement disorder.

METHODS

We measured head movements of 10 patients with functional movement disorder (F44.4, ICD-10), 10 patients with functional dizziness (F45.8, ICD-10), and (respectively) 10 healthy controls during an eye-head experiment, where participants performed large gaze shifts under normal, increased, and again normal head moment of inertia. Head oscillations at the end of the gaze shift served as a well-established marker for sensorimotor processing problems. We calculated Bayesian statistics for comparison.

RESULTS

Patients with functional movement disorder (Bayes Factor (BF)10 = 5.36, BFincl = 11.16; substantial to strong evidence) as well as patients with functional dizziness (BF10 = 2.27, BFincl = 3.56; anecdotal to substantial evidence) showed increased head oscillations compared to healthy controls, indicating marked deficits in planning and executing movement.

CONCLUSION

We replicate earlier experimental findings on erroneous sensorimotor processing in patients with functional dizziness, and show that patients with functional movement disorder show a similar impairment of sensorimotor processing during large gaze shifts. This provides an objectively measurable, transdiagnostic marker for functional disorders, highlighting important implications for diagnosis, treatment, and de-stigmatization.

Predictive Processing and the Pathophysiology of Functional Neurological Disorder

The contemporary neuroscience understanding of the brain as an active inference organ supports that our conscious experiences, including sensorimotor perceptions, depend on the integration of probabilistic predictions with incoming sensory input across hierarchically organized levels. As in other systems, these complex processes are prone to error under certain circumstances, which may lead to alterations in their outcomes (i.e., variations in sensations and movements). Such variations are an important aspect of functional neurological disorder, a complex disorder at the interface of brain-mind-body interactions. Thus, predictive processing frameworks offer fundamental mechanistic insights into the pathophysiology of functional neurological disorder. In recent years, many of the aspects relevant to the neurobiology of functional neurological disorder - e.g., aberrant motor and sensory processes, symptom expectation, self-agency, and illness beliefs, as well as interoception, allostasis, and emotion - have been investigated through the lens of predictive processing frameworks. Here, we provide an overview of the current state of research on predictive processing and the pathophysiology of functional neurological disorder.

Functional Neurological Disorder Among Sexual and Gender Minority People

Sexual and gender minority (SGM) people can face unique stressors and structural discrimination that result in higher rates of neuropsychiatric symptoms, such as depression, anxiety, and suicidality. Although more rigorous studies are needed, emerging data suggest a possible higher prevalence of functional neurological disorder and other brain-mind-body conditions in SGM people. Representation and iterative feedback from affected community members is critical to the process of developing affirming environments. More research is needed to explore the relevance of functional neurologic disorder in SGM people within a biopsychosocial framework.

The complex syndrome of functional neurological disorder

BACKGROUND

Patients with functional neurological disorders (FND) often present with multiple motor, sensory, psychological and cognitive symptoms. In order to explore the relationship between these common symptoms, we performed a detailed clinical assessment of motor, non-motor symptoms, health-related quality of life (HRQoL) and disability in a large cohort of patients with motor FND. To understand the clinical heterogeneity, cluster analysis was used to search for subgroups within the cohort.

METHODS

One hundred fifty-two patients with a clinically established diagnosis of motor FND were assessed for motor symptom severity using the Simplified Functional Movement Disorder Rating Scale (S-FMDRS), the number of different motor phenotypes (i.e. tremor, dystonia, gait disorder, myoclonus, and weakness), gait severity and postural instability. All patients then evaluated each motor symptom type severity on a Likert scale and completed questionnaires for depression, anxiety, pain, fatigue, cognitive complaints and HRQoL.

RESULTS

Significant correlations were found among the self-reported and all objective motor symptoms severity measures. All self-reported measures including HRQoL correlated strongly with each other. S-FMDRS weakly correlated with HRQoL. Hierarchical cluster analysis supplemented with gap statistics revealed a homogenous patient sample which could not be separated into subgroups.

CONCLUSIONS

We interpret the lack of evidence of clusters along with a high degree of correlation between all self-reported and objective measures of motor or non-motor symptoms and HRQoL within current neurobiological models as evidence to support a unified pathophysiology of 'functional' symptoms. Our results support the unification of functional and somatic syndromes in classification schemes and for future mechanistic and therapeutic research.

Functional Movement Disorders during COVID-19: Psychological Distress, Affective Temperament and Emotional Dysregulation

Background and objective: Functional movement disorders (FMD) represent a spectrum of psychosomatic symptoms particularly sensitive to stress. The COVID-19 pandemic has increased psychological distress worldwide and may have worsened FMD. The study aimed to confirm this hypothesis and to test whether in FMD there is a relationship between affective temperament, emotional dysregulation and psychological distress due to the pandemic. Methods: We recruited individuals with FMD, diagnosed them according to validated criteria and matched them with healthy controls (HC). Psychological distress and temperament were obtained using the Kessler-10 and the Temperament Evaluation of Memphis, Pisa and San Diego Autoquestionnaire, respectively. We used bootstrapped mediation analysis to test the mediator role of emotional dysregulation on the effect of temperament on psychological distress. Results: The sample consisted of 96 individuals. During the pandemic, 31.3% of the patients reported the need for urgent neurological care, and 40.6% reported a subjective worsening neurological condition. Patients with FMD presented with more psychological distress during the COVID-19 pandemic (F = 30.15, df = 1, p ≤ 0.001) than HC. They also reported more emotional dysregulation (F = 15.80, df = 1, p ≤ 0.001) and more cyclothymic traits (F = 14.84, df = 1, p ≤ 0.001). Cyclothymic temperament showed an indirect effect on COVID-19-related psychological distress, mediated by deficits in emotion regulation mechanisms (Bootstrapped LLCI = 0.41, ULCI = 2.41). Conclusion: Our results suggest that emotional dysregulation may represent a dimension mediating cyclotimic temperament response to the stressful effect of the pandemic and provide insight for developing intervention policies.

Approach and Clinical Practice of Functional Movement Disorders Among Neurologists in Saudi Arabia

Background Functional movement disorders (FMDs) are neurological disorders that consist of abnormal and involuntary movements that have no specific organic cause. Given the prevalence of FMDs and the scarcity of information on neurologists' approaches to FMDs, we aimed to assess the neurologists' approaches and clinical practice in managing FMDs in Saudi Arabia. Methods A validated online questionnaire in English was used. The data were collected through a self-reported questionnaire. The data were analyzed using the statistical software IBM SPSS version 22 (SPSS, Inc., Armonk, NY). Results A total of 231 neurologists completed the study survey. A total of 129 (55.8%) were males. Regarding the predictors for a diagnosis other than FMD, the highest rating predictor was for evidence of physical injury and lack of psychiatric history of psychological stressors, while the lowest rating was for the male gender. Regarding the effective treatment strategies of FMD, the most effective treatment strategy reported by the clinicians was patient education, while the least was alternative or complementary medicine. The management ability of clinicians was generally restricted by cultural beliefs about psychological illnesses and the availability of referral services. The reported predictors by clinicians for a better prognosis of FMD include acceptance of the diagnosis by the patient followed by identification and management of psychological stressors and concurrent psychiatric disorder and a supportive social network. Generally, the most used terminology in this study was "functional movement disorder". Conclusions There is a variation in the approach and clinical practice of FMD among neurologists in Saudi Arabia. Shared knowledge regarding diagnosis and effective management is crucial. Collaborative efforts are required to establish practice guidelines in the future.

Functional neurological disorder and placebo and nocebo effects: shared mechanisms

Functional neurological disorder (FND) is characterized by neurological symptoms that cannot be explained by a structural neurological cause. Among the different aetiological models that have been proposed for FND, of note is the Bayesian predictive coding model, which posits that perception relies on top-down cortical predictions (priors) to infer the source of incoming sensory information. This model can also apply to non-pathological experiences, such as placebo and nocebo effects, wherein sensory information is shaped by prior expectations and learning. To date, most studies of the relationship between placebo and nocebo effects and FND have focused on the use of placebos for diagnosis and treatment of FND. Here, we propose that this relationship might go beyond diagnosis and therapy. We develop a framework in which shared cognitive, personality and neuroanatomical factors justify the consideration of a deeper link between FND and placebo and nocebo effects. This new perspective might offer guidance for clarification of the pathogenesis of FND and for the identification of potential biomarkers and therapeutic targets.

Functional Neurological Disorders: Clinical Spectrum, Diagnosis, and Treatment

BACKGROUND

Functional neurological disorders (FNDs) are common but often misdiagnosed.

REVIEW SUMMARY

The incidence of FNDs is between 4 and 12 per 100,000, comparable to multiple sclerosis and amyotrophic lateral sclerosis, and it is the second most common diagnosis in neurology clinics. Some clues in the history are sudden onset, intermittent time course, variability of manifestation over time, childhood trauma, and history of other somatic symptoms. Anxiety and depression are common, but not necessarily more than in the general population. Although there are no tests currently capable of demonstrating whether symptoms are willfully produced, there may not be a clear categorical difference between voluntary and involuntary symptoms. The prognosis of an FND is linked to early diagnosis and symptom duration, but unfortunately, the majority of the patients are diagnosed after considerable delays.

CONCLUSIONS

A positive diagnosis of FNDs can be made on the basis of history and neurological signs without reliance on psychological stressors. Past sensitizing events and neurobiological abnormalities contribute to the pathogenesis of FNDs. Physical rehabilitation and psychological interventions alone or in combination are helpful in the treatment.

Functional Neurological Disorders in the medical education: An urgent need to fill the gaps

BACKGROUND

FND is a disabling disease that accounts for 5 to 10% of the reason for consultation in neurology. However, young physicians often say they have little or no training in their management.

AIM

The aim of the present study was to assess whether French junior neurologists, psychiatrists and physical and rehabilitation medicine (PRM) specialists received teaching on FND during their medical studies, including the residency, and to evaluate their knowledge and perception of the disorder.

METHODS

The survey was distributed by the means of a Google form questionnaire to specialist registrars and young specialists with the help of resident's organizations.

RESULTS

568 respondents from the 3 specialties were included in the study. Most respondents (72.4%) were specialists registrars. Almost half of the respondents (45.5%) answered they never received any teaching on FND, and only 20.5% of them knew the Hoover's sign, a positive sign specific of functional weakness. A large majority of respondents felt they were not sufficiently trained in FND (87.9%), and they did not have sufficient knowledge of these disorders (85.3%).

DISCUSSION

Better training would allow clinicians to make a diagnosis earlier, to better explain it to patients, and to limit the costs associated with diagnosis delays. A better training of clinicians about FND would also improve the prognosis of patients, as early diagnosis and good explanation is associated with a better prognosis.

CONCLUSION

This survey shows that there is a gap about FND in the training programs in the medical studies and during the specialization training of young doctors in France.

Stigma perceived by patients with functional somatic syndromes and its effect on health outcomes - A systematic review

BACKGROUND

Patients with functional somatic syndromes (FSS) experience stigma which arguably affects their health.

AIM

To determine the presence of perceived stigma and its effects on physical and mental health in patients with FSS compared to patients with comparable explained conditions.

METHODS

A comprehensive search of PubMed, Embase, PsycINFO, CINAHL and Cochrane Library was performed to select studies focusing on stigma perceived by patients with irritable bowel syndrome (IBS), fibromyalgia (FM) or chronic fatigue syndrome (CFS), comparing these patients to patients with comparable but explained conditions.

RESULTS

We identified 1931 studies after duplicate removal. After screening we included eight studies: one study about all three FSS, one about IBS, five about FM and one about CFS. We found that patients with IBS did not consistently experience higher levels of stigma than those with a comparable explained condition. Patients with CFS and FM experienced higher levels of stigma compared to patients with comparable explained conditions. All studies showed a correlation between stigma and negative health outcomes.

DISCUSSION

Patients with FSS experience stigma and negative health outcomes. However, experiencing stigma is not restricted to patients with FSS, as many patients with explained health conditions also experience stigma. Whether stigma has more negative health consequences in patients with FSS compared to patients with explained health conditions remains unclear and should be assessed in future research.

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.

Functional neurological disorder: lighting the way to a new paradigm for medicine

In this Essay, Mark Edwards argues that the plight of people with functional neurological disorder within healthcare highlights a general problem with a broken paradigm of modern medicine. He argues that the passivity of the traditional sick role needs replacing with a participatory, rehabilitative medical practice.

Psychedelic-assisted therapy for functional neurological disorders: A theoretical framework and review of prior reports

Functional neurological disorders (FNDs), which are sometimes also referred to as psychogenic neurological disorders or conversion disorder, are common disabling neuropsychiatric disorders with limited treatment options. FNDs can present with sensory and/or motor symptoms, and, though they may mimic other neurological conditions, they are thought to occur via mechanisms other than those related to identifiable structural neuropathology and, in many cases, appear to be triggered and sustained by recognizable psychological factors. There is intriguing preliminary evidence to support the use of psychedelic‐assisted therapy in a growing number of psychiatric illnesses, including FNDs. We review the theoretical arguments for and against exploring psychedelic‐assisted therapy as a treatment for FNDs. We also provide an in‐depth discussion of prior published cases detailing the use of psychedelics for psychosomatic conditions, analyzing therapeutic outcomes from a contemporary neuroscientific vantage as informed by several recent neuroimaging studies on psychedelics and FNDs.

A single-center series of 482 patients with functional motor disorders

Functional motor disorders (FMD) are common and disabling. They are known to predominantly affect women and young to middle-aged patients, although they also occur during childhood or in the elderly. Demographic and clinical characteristics of patients with FMD are poorly known, since large series of consecutive patients are scarce.

METHODS

In a chart review study, we retrospectively abstracted data from consecutive FMD patients who were referred to the Neurophysiology Department of the Salpêtrière University Hospital between 2008 and 2016 for treatment with repeated transcranial magnetic stimulation.

RESULTS

482 patients were included. Most patients were women (73.7%). Median age at symptoms onset was 35.5 years and symptoms were mostly characterized by acute (47.3%) or subacute (46%) onset. Only 23% of patients were active workers, while 58.3% were unemployed because of FMD. Half of the patients had functional motor weakness (n = 241) whereas the other half had movement disorders (n = 241), mainly with tremor (21.1%) or dystonia (20.5%). Among all patients, 66.4% had psychiatric comorbidity and 82.6% reported a history of trauma in the 6 months before symptoms onset. No difference was found in age or gender according to clinical phenotypes.

CONCLUSION

This large series will contribute to better characterize FMDs.

Remote delivery of cognitive behavioral therapy to patients with functional neurological disorders: Promise and challenges

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CBT is a promising treatment for patients with FND.

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Remote delivery of CBT can potentially increase access to care for patients with FND.

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Remote CBT can be integrated into clinical practice using a stepwise approach.

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Remote CBT can be integrated into practice using patient predictive factors.

Functional neurological disorders (FND) are an important source of healthcare utilization and morbidity. While there are no formal guidelines for treating these disorders, cognitive behavioral therapy (CBT) is emerging as a safe and effective treatment. Currently, there is a global shortage of CBT providers, with only a small subset trained in and comfortable with treating patients with FND. We highlight four types of remote CBT delivery to patients with FND to alleviate the access obstacle: workbooks, internet-guided CBT, app-based CBT, and teletherapy. CBT workbooks and teletherapy have been studied in FND, with preliminary studies suggesting efficacy; internet-guided CBT and app-based CBT have not but have been effectively used in patients with psychiatric disorders, particularly depression, anxiety, and post-traumatic disorders. As these disorders are often comorbid and share overlapping neurobiology with FND, internet-guided CBT and app-based CBT represent promising delivery options of CBT for FND. Although remotely-delivered CBT is unlikely to replace in-person CBT and there are technical and logistical challenges to overcome prior to widespread deployment, it holds promise as an adjunct treatment when in-person CBT is inaccessible. We propose a rational approach to future allocation of remote CBT treatment options and highlight important research gaps to bridge beforehand.

Attentional Processing and Interpretative Bias in Functional Neurological Disorder

OBJECTIVE

Altered attentional processing (automatically attending to negative or illness-relevant information) and interpretative biases (interpreting ambiguous information as negative or illness relevant) may be mechanistically involved in functional neurological disorder (FND). Common mechanisms between FND and chronic fatigue syndrome (CFS) have been proposed but not compared experimentally.

METHODS

We compared the cognitive task performance of FND, CFS, and healthy control (HC) groups. The tasks assessed attentional bias toward illness-relevant stimuli (visual probe task), attentional control (attention network task), and somatic interpretations (interpretative bias task), alongside self-reported depression, anxiety, fatigue, and general health.

RESULTS

Thirty-seven participants diagnosed with FND, 52 participants diagnosed with CFS, and 51 HC participants were included. Although participants with CFS showed attentional bias for illness-relevant stimuli relative to HC (t = -3.13, p = .002, d = 0.624), individuals with FND did not (t = -1.59, p = .118, d = 0.379). Both the FND (t = 3.08, p = .003, d = 0.759) and CFS (t = 2.74, p = .007, d = 0.548) groups displayed worse attentional control than did the HC group. Similarly, the FND (t = 3.63, p < .001, d = 0.801) and CFS groups (t = 4.58, p < .001, d = 0.909) showed more somatic interpretative bias than did the HC group.

CONCLUSIONS

Similar attentional control deficits and somatic interpretative bias in individuals with FND and CFS support potential shared mechanisms underlying symptoms. Interpretative bias toward somatic and illness-relevant stimuli in functional disorders may prove a therapeutic target.

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.

Psychiatric Comorbidities in Functional Movement Disorders: A Retrospective Cohort Study

Background

Functional movement disorders (FMD) are characterized by abnormal movements and motor symptoms incongruent with a known structural neurologic cause. While psychological stressors have long been considered an important risk factor for developing FMD, little is known about the impact of psychiatric comorbidities on disease manifestations or complexity.

Objectives

To compare characteristics of FMD patients with co-occurring mood and trauma-related psychiatric conditions to FMD patients without psychiatric conditions.

Methods

We performed a retrospective cohort study of patients seen in the University of Colorado Health system between January 1, 2015 and December 31, 2019. Patients were included if they had a diagnosis of FMD, determined by ICD-10 coding and ≥1 phenomenology-related diagnostic code (tremor, gait disturbances, ataxia, spasms, and weakness), and at least one encounter with a neurology specialist. Fisher's exact and unpaired t-tests were used to compare demographics, healthcare utilization, and phenomenologies of patients with psychiatric conditions to those with none.

Results

Our review identified 551 patients with a diagnosis of FMD who met inclusion criteria. Patients with psychiatric conditions (N = 417, 75.7%) had increased five-year healthcare utilization (mean emergency room encounters 9.9 vs. 3.5, P = 0.0001) and more prevalent non-epileptic seizures (18.2% vs. 7.5%, P = 0.001). Suicidal ideation (8.4%) and self-harm (4.1%) were only observed amongst patients with comorbid psychiatric conditions.

Conclusions

Patients with FMD and comorbid psychiatric conditions require more healthcare resources and have greater disease complexity than patients without psychiatric illness. This may have implications for treatment of patients without comorbid psychiatric conditions who may benefit from targeted physiotherapy alone.

Reliability of additional reported seizure manifestations to identify dissociative seizures

PURPOSE

Descriptions of seizure manifestations (SM), or semiology, can help localize the symptomatogenic zone and subsequently included brain regions involved in epileptic seizures, as well as identify patients with dissociative seizures (DS). Patients and witnesses are not trained observers, so these descriptions may vary from expert review of seizure video recordings of seizures. To better understand how reported factors can help identify patients with DS or epileptic seizures (ES), we evaluated the associations between more than 30 SMs and diagnosis using standardized interviews.

METHODS

Based on patient- and observer-reported data from 490 patients with diagnoses documented by video-electoencephalography, we compared the rate of each SM in five mutually exclusive groups: epileptic seizures (ES), DS, physiologic seizure-like events (PSLE), mixed DS and ES, and inconclusive testing.

RESULTS

In addition to SMs that we described in a prior manuscript, the following were associated with DS: light triggers, emotional stress trigger, pre-ictal and post-ictal headache, post-ictal muscle soreness, and ictal sensory symptoms. The following were associated with ES: triggered by missing medication, aura of déjà vu, and leftward eye deviation. There were numerous manifestations separately associated with mixed ES and DS.

CONCLUSIONS

Reported SM can help identify patients with DS, but no manifestation is pathognomonic for either ES or DS. Patients with mixed ES and DS reported factors divergent from both ES-alone and DS-alone.

Nocebo-Hypothesis Cognitive Behavioral Therapy (NH-CBT) for Persons With Functional Neurological Symptoms (Motor Type): Design and Implementation of a Randomized Active-Controlled Trial

Introduction: Functional Neurological Symptom Disorders (FNSD) are associated with high levels of disability and immense direct and indirect health costs. An innovative interdisciplinary rehabilitation approach for individuals with functional neurological symptoms of motor type–Nocebo-Hypothesis Cognitive Behavioral Therapy (NH-CBT)—combines CBT and movement retraining with video feedback embedded in a comprehensive explanatory model of the etiology of FNSD.

Methods: This protocol describes the development and implementation of a phase II, parallel group, randomized controlled trial with blinded outcome assessors to compare the efficacy of NH-CBT with an active control condition (supportive counseling and movement retraining). Individuals meeting diagnostic criteria of an FNSD or psychogenic movement disorder will be randomly assigned to one of the 8-week interventions. Self-report scales of motor and other physical symptoms, symptom-related psychological variables, and assessor ratings of participants' mobility will be administered at baseline, and at 8- and 16-week follow-up. Adverse events will be monitored across all sessions and therapeutic alliance will be measured at the end of therapy. The primary statistical analysis will test the hypothesis that NH-CBT is more effective than the control intervention at the 8-week follow-up.

Discussion: The therapeutic strategies of NH-CBT are theory-driven by assumptions of the predictive coding model of the etiology of FNSD. Strengths and limitations of this trial will be discussed.

Trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR; identifier: ACTRN12620000550909).

Association Between Somatization and Nonmotor Symptoms Severity in People With Parkinson Disease

OBJECTIVE

To assess the frequency of somatization and its association with motor, nonmotor symptoms, and quality of life in persons with Parkinson disease (PD).

METHODS

A cross-sectional case-control study was carried out. Assessments included the List of 90 Symptoms somatic factor (SCL-90-R SOM), Movement Disorder Society Unified Parkinson's Ratings Scale (MDS-UPDRS), Non-Motor Symptom Scale (NMSS), Montreal Cognitive Assessment (MoCA), and Parkinson Questionnaire-8 (PDQ-8).

RESULTS

A total 93 persons with PD and 93 controls were included. Somatization within the PD group was 2 times more frequent compared to the control group (43% vs 21.5%, P = .003). Persons with PD had higher NMSS total scores (48.6 ± 42.6 vs 28.3 ± 30.4, P = .001). Patients with PD with somatization had worst MDS-UPDRS, NMSS, MoCA, and PDQ-8 (all P < .05).

CONCLUSION

Somatization is more frequent in persons with PD compared to healthy controls. Somatization in PD is associated with nonmotor symptoms and worst quality of life.

Stigma and functional neurological disorder: a research agenda targeting the clinical encounter

Stigma against patients with functional neurological disorder (FND) presents obstacles to diagnosis, treatment, and research. The lack of biomarkers and the potential for symptoms to be misunderstood, invalidated, or dismissed can leave patients, families, and healthcare professionals at a loss. Stigma exacerbates suffering and unmet needs of patients and families, and can result in poor clinical management and prolonged, repetitive use of healthcare resources. Our current understanding of stigma in FND comes from surveys documenting frustration experienced by providers and distressing healthcare interactions experienced by patients. However, little is known about the origins of FND stigma, its prevalence across different healthcare contexts, its impact on patient health outcomes, and optimal methods for reduction. In this paper, we set forth a research agenda directed at better understanding the prevalence and context of stigma, clarifying its impact on patients and providers, and promoting best practices for stigma reduction.

Functional Motor Symptoms in Parkinson's Disease and Functional Parkinsonism: A Systematic Review

OBJECTIVE

Whereas functional symptoms are common in Parkinson's disease (PD), a parkinsonian syndrome may occasionally reflect a pure functional disorder (also named functional parkinsonism [FP]). This review aimed to decipher these entities to clarify the link between functional manifestations and PD.

METHODS

Following the PRISMA guidelines, the authors performed a systematic literature search of the PubMed and Science Direct databases for the period 1988 to December 2018 to identify studies of patients with either FP or PD associated with functional neurological symptoms.

RESULTS

From the 844 articles screened, 22 were retained, including 12 studies of functional neurological symptoms in PD and 16 studies of FP. The studies of functional symptoms in PD included 121 patients-57% were women, and the mean age was 61.3 years. Psychiatric history (mostly depression) and exposure to triggering stressors were frequent: 60% and 82.5%, respectively. The most common symptom was tremor (33.8%), most often located on the side most affected by PD (50%). Studies of FP included a total of 120 patients-62% were women, and the mean age was 50.7 years. The first FP symptoms appeared on average 5 years before diagnosis, with an abrupt onset in half the cases; 67.6% had a psychiatric history, and 46.8% were exposed to triggering stressors, such as physical injury, stress at work, or loss of family or friends.

CONCLUSIONS

Findings suggest a possible relationship between PD and FP. Clinicians should keep in mind the possibility of functional symptoms in PD patients.

Outpatient Physical Therapy for Functional Neurological Disorder: A Preliminary Feasibility and Naturalistic Outcome Study in a U.S. Cohort

OBJECTIVE

Despite promising research and consensus recommendations on the important therapeutic role of physical therapy for motor functional neurological disorder (FND), little is known about the feasibility and potential efficacy of implementing physical therapy for this population in a U.S.-based outpatient program. Given health care system differences internationally, this is an important gap in the literature.

METHODS

In this retrospective cohort study, the authors investigated the relationship between treatment adherence and clinical outcome in a hospital-based outpatient physical therapy clinical program. Medical records of 50 consecutive patients with motor FND referred from an FND clinical program were reviewed. The physical therapy intervention included a 1-hour initial assessment and the development of individualized treatment plans guided by published consensus recommendations. Statistical analyses included nonparametric, univariate screening tests followed by multivariate regression analyses.

RESULTS

In univariate analyses, there was a statistically significant positive correlation between the number of sessions attended and clinical improvement. This relationship held when adjusting for demographic variables, concurrent psychogenic nonepileptic seizures, and other major neurological comorbidities. In a post hoc analysis of the subset of individuals with available gait speed data, posttreatment 10-meter gait speed times improved compared with baseline measurements. Baseline neuropsychiatric factors did not correlate with clinical improvement.

CONCLUSIONS

This preliminary, retrospective cohort study demonstrated that treatment adherence to a U.S.-based outpatient physical therapy program was associated with clinical improvement. Prospective observational and randomized controlled trials are needed to further optimize physical therapy for patients with functional motor symptoms in the outpatient setting.

Internal Versus External Frame of Reference in Functional Movement Disorders

OBJECTIVE

The purpose of this study was to determine whether patients with functional movement disorders (FMDs) differ in their internal versus external locus of control (LOC) and whether LOC in these patients affected disease severity, quality of life, and functional impairment compared with control subjects with degenerative (Parkinson's disease) and nondegenerative (focal dystonia) neurological conditions.

METHODS

A total of 156 patients with FMD (N=45), Parkinson's disease (N=64), and focal dystonia (N=47) were recruited between June 2015 and August 2017. The authors administered the general Levenson Multidimensional LOC (LOC-G) and health-specific Multidimensional Health LOC (LOC-H) scales. An internal LOC was represented similarly in both scales: the external LOC included "chance" and "powerful others" in the LOC-G measure and chance, "other people," and "doctors" in the LOC-H measure. Quality of life, functional impairment, and FMD severity were assessed. One-way analysis of variance and adjusted logistic regressions were used, as well as ordinary least-squares between and within groups, respectively.

RESULTS

Patients with FMD had lower external chance LOC-G scores compared with patients in the Parkinson's disease group (odds ratio=0.90, p=0.03) and higher internal (odds ratio=1.22, p=0.01) and lower external (odds ratio=0.77, p=0.02) doctors LOC-H scores compared with patients in the focal dystonia group. External powerful others LOC-G score was associated with functional impairment (regression coefficient=-0.04, p=0.02). There were no effects of LOC on quality of life or disease severity.

CONCLUSIONS

Patients with FMD exhibited high "within our control" internal general and health-specific frame of reference. LOC had no influence on quality of life or disease severity in this patient population.

What is it like to live with a functional movement disorder? An interpretative phenomenological analysis of illness experiences from symptom onset to post-diagnosis

OBJECTIVES

With few empirically supported treatments, functional movement disorders (FMD) can be challenging to manage. To enable service providers to better support people with FMD, this study sought to understand the lived experience of FMD: to gain insight into how individuals make sense of their experience from symptom onset through medical evaluation and diagnosis to post-diagnostic adaptation.

DESIGN

An interpretative phenomenological analysis (IPA) of patient accounts of living with FMD.

METHODS

Eight participants were recruited from a UK teaching hospital adult neurology service: seven females, varying in age (20s-70s), FMD symptom type (tremor, dystonia, and tics), and time to diagnosis (10 - 192 months). Semi-structured interviews facilitated participant accounts of key events. Interviews lasted 75-125 minutes and were transcribed verbatim.

RESULTS

Three super-ordinate themes were apparent. The first covered the experiences of onset ('Something is wrong with me'), including loss of control - with the affected body part often described as a separate entity - threats to identity and disturbance in relationships. 'At last! What now?' outlined the bittersweet experience of diagnosis and of treatments. Third, 'Living my life with it' incorporated ongoing experiences of coping with symptoms. While some continued to struggle with the emotional impact of symptoms, others developed a compassionate relationship with their self and maintained satisfying activities.

CONCLUSIONS

FMD has a significant impact on patients' relationships with themselves and others, which in turn affects well-being. These findings suggest some nuanced additions to interventions (diagnosis, psychotherapy, physiotherapy, public education.).

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.

Clinical Correlates of Functional Motor Disorders: An Italian Multicenter Study

Background

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

Objective

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

Methods

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

Results

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

Conclusions

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

Can Pallidal Deep Brain Stimulation Rescue Borderline Dystonia? Possible Coexistence of Functional (Psychogenic) and Organic Components

The diagnosis and treatment of functional movement disorders are challenging for clinicians who manage patients with movement disorders. The borderline between functional and organic dystonia is often ambiguous. Patients with functional dystonia are poor responders to pallidal deep brain stimulation (DBS) and are not good candidates for DBS surgery. Thus, if patients with medically refractory dystonia have functional features, they are usually left untreated with DBS surgery. In order to investigate the outcome of functional dystonia in response to pallidal DBS surgery, we retrospectively included five patients with this condition. Their dystonia was diagnosed as organic by dystonia specialists and also as functional according to the Fahn and Williams criteria or the Gupta and Lang Proposed Revisions. Microelectrode recordings in the globus pallidus internus of all patients showed a cell-firing pattern of bursting with interburst intervals, which is considered typical of organic dystonia. Although their clinical course after DBS surgery was incongruent to organic dystonia, the outcome was good. Our results question the possibility to clearly differentiate functional dystonia from organic dystonia. We hypothesized that functional dystonia can coexist with organic dystonia, and that medically intractable dystonia with combined functional and organic features can be successfully treated by DBS surgery.

Dissociated motor learning and de-adaptation in patients with functional gait disorders

Walking onto a stationary platform that had been previously experienced as moving generates a locomotor after-effect—the so-called ‘broken escalator’ phenomenon. The motor responses that occur during locomotor after-effects have been mapped theoretically using a hierarchal Bayesian model of brain function that takes into account current sensory information that is weighted according to prior contextually-relevant experiences; these in turn inform automatic motor responses. Here, we use the broken escalator phenomenon to explore motor learning in patients with functional gait disorders and probe whether abnormal postural mechanisms override ascending sensory information and conscious intention, leading to maladaptive and disabling gait abnormalities. Fourteen patients with functional gait disorders and 17 healthy control subjects walked onto a stationary sled (‘Before’ condition, five trials), then onto a moving sled (‘Moving’ condition, 10 trials) and then again onto the stationary sled (‘After’ condition, five trials). Subjects were warned of the change in conditions. Kinematic gait measures (trunk displacement, step timing, gait velocity), EMG responses, and subjective measures of state anxiety/instability were recorded per trial. Patients had slower gait velocities in the Before trials (P &lt; 0.05) but were able to increase this to accommodate the moving sled, with similar learning curves to control subjects (P = 0.87). Although trunk and gait velocity locomotor after-effects were present in both groups, there was a persistence of the locomotor after-effect only in patients (P &lt; 0.05). We observed an increase in gait velocity during After trials towards normal values in the patient group. Instability and state anxiety were greater in patients than controls (P &lt; 0.05) only during explicit phases (Before/After) of the task. Mean ‘final’ gait termination EMG activity (right gastrocnemius) was greater in the patient group than controls. Despite a dysfunctional locomotor system, patients show normal adaptive learning. The process of de-adaptation, however, is prolonged in patients indicating a tendency to perpetuate learned motor programmes. The trend to normalization of gait velocity following a period of implicit motor learning has implications for gait rehabilitation potential in patients with functional gait disorders and related disorders (e.g. fear of falling).

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

Nonepileptic attack disorder (NEAD) and functional movement disorder (FMD) are functional neurological disorders commonly seen in neuropsychiatry services. Although their initial referral pathways involve epileptologists (NEAD) and specialists in movement disorders (FMD), these conditions are currently classified as two possible manifestations of a single underlying conversion disorder. We set out to compare the characteristics of patients with NEAD and patients with FMD in order to quantify the degree of overlap between these patient groups. We retrospectively reviewed comprehensive clinical data from 146 consecutive patients with functional neurological disorders (NEAD: n = 117; FMD: n = 29) attending a specialist Neuropsychiatry Clinic run by a single Consultant in Behavioral Neurology. The two clinical groups were directly compared with regard to demographic and clinical characteristics, as well as somatic and psychiatric presentations. The results showed that in most features, there were no significant differences between patients with NEAD and patients with FMD. However, patients with NEAD reported an earlier age at onset (p = 0.033) and a higher proportion of acute onset (p = 0.037), alterations of consciousness (p = 0.001), and headache (p = 0.042), whereas patients with FMD reported a higher prevalence of childhood abuse (p = 0.008), as well as mobility problems (p = 0.007) and comorbid functional symptoms (dysarthria, p = 0.004; dizziness, p = 0.035; weakness, p = 0.049). Despite different phenotypic presentations, NEAD and FMD might represent a clinical continuum, with relevant implications in terms of both diagnostic strategies and treatment approaches.

Raised visual contrast thresholds with intact attention and metacognition in functional motor disorder

Functional motor disorders (FMDs) are distinguished by signs that lack congruence with recognised patterns of organic disease and show inconsistency over time. Their pathophysiology is poorly understood, but there is evidence that irregularities in perceptual and cognitive processing lie at the heart of these conditions. Here, we draw on a predictive coding account of functional neurological disorders to study perceptual decision-making in three groups: 20 patients with FMDs (14 with functional movements and 6 with functional weakness), 20 with phenotypically-matched organic motor disorders, and 20 age-matched healthy controls. We examine four cognitive domains with putative roles in FMD pathogenesis: attention, expectations, sensory processing (perceptual sensitivity), and metacognition (introspective evaluation of performance). We augmented a dual-task paradigm, manipulating the visual contrast required for target detection to examine these domains in one design. With sensory input (stimulus contrast) psychometrically adjusted to staircase target detection at a fixed level for all groups, the FMD group exhibited statistically equivalent attentional, expectational and metacognitive processing to healthy controls. However, we demonstrate Bayesian evidence and a frequentist trend that FMD patients require higher visual contrast than controls to maintain the same detection sensitivity (BF₁₀ = 8.1, p_holm = .066). This was statistically equivalent to the visual contrast required by the organic group, and unlikely to be accounted for by medication use or comorbid psychopathology. The organic group showed differences in processing of attention and expectations for target detection that were not observed in either healthy controls or the functional group. The distinctive behavioural profile of FMDs may arise from abnormalities in basic sensory processing, while higher attentional, expectational and metacognitive mechanisms remain intact. Conceptualising functional neurological disorders under a predictive coding account may consolidate and refine existing pathophysiological theories about them.

Similar association between objective and subjective symptoms in functional and organic tremor

BACKGROUND

A previous study reported a dramatic mismatch in objectively detected and self-reported tremor duration in patients with functional tremor. As these findings have an important and widespread impact in both clinical care and research, we conducted a validation study with a longer study duration and a larger sample of patients.

METHODS

Fourteen patients with functional tremor and 19 with organic tremor completed a 30 day study period. Objective tremor duration was recorded using a wrist-worn accelerometer. Simultaneously, participants completed a web-based diary five times a day, each time rating their symptom burden since the previous diary entry.

RESULTS

Patients with functional tremor had shorter objective tremor duration compared to patients with organic tremor (21.6% vs 30.7%, P = 0.034). A post-hoc analysis revealed the difference in objective duration was mainly due to patients with essential tremor (37.2%). Subjective symptom burden was not significantly different between functional and organic tremors (38.7 vs 28.7 on a 0-100 VAS scale, P = 0.138). Finally, a mixed model analysis did not reveal significant differences in the association between subjective and objective tremor symptoms (P = 0.168).

CONCLUSIONS

patients with functional tremor do have an objectively detectable, persistent tremor during daily life activities. Furthermore, they have a similar symptom burden and a similar association between subjective and objective tremor symptoms as patients with organic tremor.

Medication prescriptions in 322 motor functional neurological disorder patients in a large UK mental health service: A case control study

OBJECTIVE

This study describes medication prescribing patterns in patients with motor functional neurological disorder (mFND) treated in South London and Maudsley NHS Foundation Trust (SLaM), comparing outcomes to a control group of psychiatric patients from the same hospital trust.

METHOD

This is a retrospective case-control study using a psychiatric case register. Cross-sectional data were obtained from 322 mFND patients and 644 psychiatry controls who had had contact with SLaM between 1st January 2006 and 31st December 2016.

RESULTS

A slightly lower proportion of mFND patients received medication compared to controls (76.6% v. 83.4%, OR: 0.59, CI: 0.39-0.89, p < 0.05). Of medication recipients, mFND patients were prescribed a higher number of agents (mean: 4.7 v 2.9, p = 0.001) and had higher prescription rates of antidepressants, anti-epileptics, analgesics, and certain non-psychotropic medications. Higher numbers of prescriptions were associated with co-morbid physical conditions, and previous psychiatric admissions.

CONCLUSIONS

This is the first study to describe medication prescriptions in a large cohort of mFND patients. Patients were prescribed a wide range of psychiatric and physical health medications, with higher rates of polypharmacy than controls. Psychotropic medication prescription is not necessarily the first line treatment for mFND, where physiotherapy and psychotherapy may be offered initially. There is limited, early-phase evidence for pharmacological therapies for mFND, and as such, the benefit-to-risk ratio of prescribing in this complex and poorly understood disorder should be carefully assessed.

Quality of life in functional movement disorders is as altered as in organic movement disorders

OBJECTIVE

Patients with functional movement disorders (FMD) often report a disability and psychiatric comorbidities. However, few studies have compared these aspects in FMD and in organic movement disorders (OMD). The objectives were to compare QoL and psychiatric comorbidities of FMD and OMD patients.

METHODS

Twenty-one and 30 FMD patients were compared to 21 and 30 sex- and age-matched dystonia and Parkinson patients respectively. QoL was assessed using the Parkinson's Disease Summary Index (PDSI). Psychiatric comorbidities were screened with the Mini International Neuropsychiatric Interview, the Hospital Anxiety and Depression Scale and the Composite International Diagnostic Interview questionnaire.

RESULTS

QoL was more altered in FMD than in dystonia on PDSI (42.1 vs 25.1; p = .003). No significant difference was observed in QoL in FMD and Parkinson's disease on PDSI (38.3 vs 32.2; p = .61). Moreover, FMD patients were more often unemployed because of their condition than dystonia (61.9% vs 14.3%; p = .01) and Parkinson patients (53.3% vs 13.3%; p = .005). The occurrence of anxiety (p = .58 and > 0.99), depression (p = .77 and 0.77), and traumatic events (p = .58 and 0.75) was not different between groups. FMD patients reported more often sexual abuse than dystonia (28,6% vs 4.8%; p = .13) and Parkinson patients (23.3% vs 0.0%; p = .02).

CONCLUSION

FMD patients presented a significant alteration of QoL and no increased psychiatric comorbidities compared to OMD patients. These results highlight the impact of FMD and suggest that neurologists should be as involved in the management of FMD as they are in OMD.

Functional Movement Disorders and Placebo: A Brief Review of the Placebo Effect in Movement Disorders and Ethical Considerations for Placebo Therapy

Background

Functional movement disorders are common and disabling neurologic conditions. Patients with functional neurologic disorders represent a large proportion of neurology clinic referrals, and limited availability of subspecialty care creates a considerable burden for the healthcare system. These conditions are currently treated with a combination of physical therapy and cognitive behavioral therapy, with variable success.

Methods

We searched the Medline database for studies on the epidemiology and physiology of functional movement disorders, as well as those on the placebo effect in movement disorders. We reviewed and summarized the literature on these topics and explored ethical issues concerning the administration of placebos to patients with functional movement disorders.

Results

Studies of placebos, particularly in patients with movement disorders, have shown that these "inert" agents can provide demonstrable neurophysiologic benefits, even in open-label studies. Physician surveys have shown that many administer placebos for diagnostic and therapeutic purposes, although there are ethical concerns about this practice. We used a principle-based approach and reviewed ethical arguments for (justice and beneficence) and against (non-maleficence and autonomy) the use of placebos in functional movement disorders. In this context, we argue for the importance of the therapeutic alliance in preserving patient autonomy while exploring the potential benefits of placebo therapy.

Conclusions

An ethical argument is presented in support of nondeceptive clinical placebo use for the treatment of functional movement disorders. Patient and clinician attitudes regarding the use of placebos should be investigated before placebo-therapy trials are conducted.

The impact of non-motor symptoms on the health-related quality of life in patients with functional movement disorders

OBJECTIVE

Pain, fatigue, cognitive complaints and psychiatric comorbidities are common in patients with functional movement disorder and may significantly affect their quality of life. The aim of the study was to assess the impact of motor and non-motor symptoms on health-related quality of life in patients with functional movement disorder.

METHODS

Sixty-one patients with clinically established functional movement disorder and 61 matched healthy controls completed standardized questionnaires for depression, anxiety, cognitive complaints, fatigue, pain, sleepiness, apathy and health-related quality of life. Motor disorder severity was assessed using The Simplified Functional Movement Disorders Rating Scale. Personality traits were assessed using the 44-Item Big Five Inventory.

RESULTS

Compared to controls, patients reported significantly lower health-related quality of life and higher levels of all assessed non-motor symptoms except for apathy. No difference was found in personality traits. In both groups, health-related quality of life scores negatively correlated with depression, anxiety, pain, cognitive complaints, apathy, and neuroticism. No correlation was found between health-related quality of life and motor symptom severity in patients with functional movement disorder. Multiple regression analysis of the predictors of health-related quality of life showed significant impact of trait anxiety and cognitive complaints scores.

CONCLUSIONS

Multiple non-motor symptoms but not motor symptom severity correlated with impaired health-related quality of life in patients with functional movement disorder. Impaired health-related quality of life was predicted by anxiety and cognitive complaints. Our results highlight the importance of assessing and treating both motor and non-motor symptoms in patients with functional movement disorder.

Functional neurological disorders: acute presentations and management

Functional neurological disorders (FND) are common and associated with significant morbidity and healthcare costs. Patients with FND often present acutely, particularly with dissociative seizures (resembling epilepsy) or persistent weakness resembling a stroke. History and careful observation and examination are critical to diagnosis, as investigations will often be normal or non-contributory. The nature of convulsive movements in dissociative seizures often differs from that in epilepsy, and long duration of individual events, waxing and waning, closed eyes and high reported frequency in an apparently well individual are all suggestive. In those with stroke-like episodes, demonstration of normal power even briefly (eg Hoover's sign, 'give way' weakness) together with distractability are positive physical features indicating a functional disorder. A positive diagnosis and clear non-judgemental explanation, backed up by reliable information sources associated with prompt onward referral to a neurologist can greatly reduce distress and ultimately improve outcomes.

Occupational therapy for functional neurological disorders: a scoping review and agenda for research

Functional neurological disorders (FND)-also called psychogenic, nonorganic, conversion, and dissociative disorders-constitute one of the commonest problems in neurological practice. An occupational therapist (OT) is commonly involved in management, but there is no specific literature or guidance for these professionals. Classification now emphasizes the importance of positive diagnosis of FND based on physical signs, more than psychological features. Studies of mechanism have produced new clinical and neurobiological ways of thinking about these disorders. Evidence has emerged to support the use of physiotherapy and occupational therapy as part of a multidisciplinary team for functional movement disorders (FMD) and psychotherapy for dissociative (nonepileptic) attacks. The diagnosis and management of FND has entered a new evidence-based era and deserves a standard place in the OT neurological curriculum. We discuss specific management areas relevant to occupational therapy and propose a research agenda.

Functional neurological disorders in Parkinson disease

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Motor Retraining (MoRe) for Functional Movement Disorders: Outcomes From a 1-Week Multidisciplinary Rehabilitation Program

BACKGROUND

Functional movement disorders (FMDs) are conditions of abnormal motor control thought to be caused by psychological factors. These disorders are commonly seen in neurologic practice, and prognosis is often poor. No consensus treatment guidelines have been established; however, the role of physical therapy in addition to psychotherapy has increasingly been recognized. This study reports patient outcomes from a multidisciplinary FMD treatment program using motor retraining (MoRe) strategies.

OBJECTIVE

To assess outcomes of FMD patients undergoing a multidisciplinary treatment program and determine factors predictive of treatment success.

DESIGN

Retrospective chart review.

SETTING

University-affiliated rehabilitation institute.

PATIENTS

Thirty-two consecutive FMD patients admitted to the MoRe program from July 2014-July 2016.

INTERVENTION

Patients participated in a 1-week, multidisciplinary inpatient treatment program with daily physical, occupational, speech therapy, and psychotherapy interventions.

MAIN OUTCOME MEASUREMENTS

Primary outcome measures were changes in the patient-rated Clinical Global Impression Scale (CGI) and the physician-rated Psychogenic Movement Disorder Rating Scale (PMDRS) based on review of standardized patient videos. Measurements were taken as part of the clinical evaluation of the program.

RESULTS

Twenty-four of the 32 patients were female with a mean age of 49.1 (±14.2) years and mean symptom duration of 7.4 (±10.8) years. Most common movement phenomenologies were abnormal gait (31.2%), hyperkinetic movements (31.2%), and dystonia (31.2%). At discharge, 86.7% of patients reported symptom improvement on the CGI, and self-reported improvement was maintained in 69.2% at the 6-month follow-up. PMDRS scores improved by 59.1% from baseline to discharge. Longer duration of symptoms, history of abuse, and comorbid psychiatric disorders were not significant predictors of treatment outcomes.

CONCLUSIONS

The majority of FMD patients experienced improvement from a 1-week multidisciplinary inpatient rehabilitation program. Treatment outcomes were not negatively correlated with longer disease duration or psychiatric comorbidities. The results from our study are encouraging, although further long-term prospective randomized studies are needed.

LEVEL OF EVIDENCE

III.

[Clinical and cognitive aspects of functional (psychogenic) tremor]

Functional (psychogenic) tremor is the most common functional movement disorder. Characteristic clinical features, so called red flags, can help to make the clinical distinction of this type from other tremor disorders. The most common features include the variability of frequency and amplitude. Clinical examination should include different types of distraction including motor or cognitive tasks or testing the influence of suggestibility on tremor amplitude, frequency or direction. Patients often report sudden onset and remissions that may last for months or even years. In some cases, the tremor is only present in highly specific situations. Although functional tremor shares characteristics with voluntary actions, patients experience their abnormal movements as involuntary. Recent experimental approaches have revealed an impairment in sense of agency. The diagnosis can be supported by neurophysiological measurements including accelerometry, which achieved a sensitivity of 89.5% and a specificity of 95.9% in a validated test battery, thus providing a useful additional diagnostic tool. Psychotherapeutic treatment is indicated in patients with and without evident psychological symptoms. A specific physiotherapeutic approach for functional tremor is re-trainment.

Functional (psychogenic) gait disorder: diagnosis and management

Functional (psychogenic) gait disorders are a common presentation of functional neurological disorder - one of the commonest diagnoses made in neurology practice. People with functional neurological disorder are as disabled and experience as poor a quality of life as patients with multiple sclerosis and Parkinson's disease. People with functional neurological disorder, including gait disorder, are often perceived as being challenging to diagnose and manage, and as a result attitudes of health professionals towards them are often negative. However, a rapid positive diagnosis of functional gait disorder can often be made, and with a specific approach to diagnostic explanation and treatment, many patients experience improvement in symptoms and disability, with such improvements sustained in the long term. Here I review current evidence regarding the diagnosis, pathophysiology and management of functional gait disturbance with an emphasis on how to make a positive diagnosis and how to select the most appropriate treatment approach. Rehabilitative treatments, with an emphasis on specific physiotherapy interventions, have increasing evidence for benefit, particularly if carried out following a comprehensive explanation of the diagnosis.