Is there a specific psychiatric background or personality profile in functional dystonia?

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.

Personality traits related to cognitive functioning in patients with functional neurological disorder

Cognitive symptoms are prevalent in patients with functional neurological disorder (FND). Several studies have suggested that personality traits such as neuroticism may play a pivotal role in the development of FND. FND has also been associated with alexithymia: patients with FND report difficulties in identifying, analyzing, and verbalizing emotions. Whether or not alexithymia and other personality traits are associated with cognitive symptomatology in patients with FND is unknown. In the current study, we explored whether the Big Five personality model factors (neuroticism, extraversion, openness, agreeableness, and conscientiousness) and alexithymia were associated with cognitive functioning in FND. Twenty-three patients with FND were assessed using a neuropsychological assessment and questionnaire assessment to explore personality traits (Neuroticism-Extraversion-Openness Five-Factor Inventory) and alexithymia (Bermond-Vorst Alexithymia Questionnaire). The results indicated that high conscientiousness was associated with lower planning scores (ρ = -0.52, p = .012) and high scores on alexithymia were associated with lower scores on verbal memory scores (ρ = -0.46, p = .032) and lower sustained attention scores (ρ = -0.45, p = .046). The results did not remain significant after controlling for multiple testing. The preliminary results of our study suggest that personality and cognitive symptomatology in patients with FND are topics that should be further explored in future studies, as cognitive symptomology can affect treatment results.

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.

Case Report: Guitarist's cramp as the initial manifestation of dopa-responsive dystonia with a novel heterozygous GCH1 mutation

Dopa-responsive dystonia (DRD), also known as Segawa syndrome, is a phenotypically and genetically heterogeneous group of neurological disorders that typically presents as early-onset lower limb dystonia with diurnal fluctuation, and exhibits a marked, persistent response to levodopa. Heterozygous loss-of-function mutations in the guanosine triphosphate cyclohydrolase 1 (GCH1) are the most common cause of DRD. In addition to the classic form of the disease, there have been a number of studies addressing atypical clinical features of GCH1 related DRD with variable age of onset. This report describes a 37-year-old Japanese male patient with a 10-year history of focal upper limb dystonia that initially emerged as task-specific, guitarist’s cramp. The dystonic symptoms responded very well to levodopa treatment, and genetic analysis identified a novel heterozygous mutation in the C-terminal catalytic domain of GCH1. Insufficient recognition of this treatable condition often leads to misdiagnosis, which causes delays in the patient receiving adequate dopamine replenishing therapy. A diagnostic trial with levodopa should be considered in all patients with relatively young-onset dystonia, whether they have classic features of DRD or not.

The prevalence of depression in adult onset idiopathic dystonia: Systematic review and metaanalysis

Adult onset idiopathic dystonia (AOID) is the third most common movement disorder in adults. Co-existing depressive symptoms and disorders represent major contributors of disability and quality of life in these patients, but their prevalence remains unclear. We investigated the point prevalence of supra-clinical threshold depressive symptoms/depressive disorders in AOID in a systematic review with qualitative synthesis and meta-analysis. Our search identified 60 articles suitable for qualitative synthesis and 54 for meta-analysis. The overall pooled prevalence of either supra-clinical threshold depressive symptoms or depressive disorders was 31.5 % for cervical dystonia, 29.2 % for cranial dystonia, and 33.6 % for clinical samples with mixed forms of AOID. Major depressive disorder was more prevalent than dysthymia in cervical dystonia, whereas dysthymia was more prevalent in cranial dystonia. In cervical dystonia, the prevalence of supra-clinical threshold depressive symptoms screened by rating scales was higher than that of depressive disorders diagnosed with structured interviews. Prevalence studies using rating scales yielded higher heterogeneity. More research is warranted to standardize screening methodology and characterization of mood disorders in AOID.

Functional Dystonia: Differentiation From Primary Dystonia and Multidisciplinary Treatments

Dystonia is a common movement disorder, involving sustained muscle contractions, often resulting in twisting and repetitive movements and abnormal postures. Dystonia may be primary, as the sole feature (isolated) or in combination with other movement disorders (combined dystonia), or as one feature of another neurological process (secondary dystonia). The current hypothesis is that dystonia is a disorder of distributed brain networks, including the basal ganglia, cerebellum, thalamus and the cortex resulting in abnormal neural motor programs. In comparison, functional dystonia (FD) may resemble other forms of dystonia (OD) but has a different pathophysiology, as a subtype of functional movement disorders (FMD). FD is the second most common FMD and amongst the most diagnostically challenging FMD subtypes. Therefore, distinguishing between FD and OD is important, as the management of these disorders is distinct. There are also different pathophysiological underpinnings in FD, with for example evidence of involvement of the right temporoparietal junction in functional movement disorders that is believed to serve as a general comparator of internal predictions/motor intentions with actual motor events resulting in disturbances in self-agency. In this article, we present a comprehensive review across the spectrum of FD, including oromandibular and vocal forms and discuss the history, clinical clues, evidence for adjunctive "laboratory-based" testing, pathophysiological research and prognosis data. We also provide the approach used at the Massachusetts General Hospital Dystonia Center toward the diagnosis, management and treatment of FD. A multidisciplinary approach, including neurology, psychiatry, physical, occupational therapy and speech therapy, and cognitive behavioral psychotherapy approaches are frequently required; pharmacological approaches, including possible targeted use of botulinum toxin injections and inpatient programs are considerations in some patients. Early diagnosis and treatment may help prevent unnecessary investigations and procedures, while facilitating the appropriate management of these highly complex patients, which may help to mitigate frequently poor clinical outcomes.

Are there two different forms of functional dystonia? A multimodal brain structural MRI study

This study assessed brain structural alterations in two diverse clinical forms of functional (psychogenic) dystonia (FD) - the typical fixed dystonia (FixFD) phenotype and the "mobile" dystonia (MobFD) phenotype, which has been recently described in one study. Forty-four FD patients (13 FixFD and 31 MobFD) and 43 healthy controls were recruited. All subjects underwent 3D T1-weighted and diffusion tensor (DT) magnetic resonance imaging (MRI). Cortical thickness, volumes of gray matter (GM) structures, and white matter (WM) tract integrity were assessed. Normal cortical thickness in both FD patient groups compared with age-matched healthy controls were found. When compared with FixFD, MobFD patients showed cortical thinning of the left orbitofrontal cortex, and medial and lateral parietal and cingulate regions bilaterally. Additionally, compared with controls, MobFD patients showed reduced volumes of the left nucleus accumbens, putamen, thalamus, and bilateral caudate nuclei, whereas MobFD patients compared with FixFD demonstrated atrophy of the right hippocampus and globus pallidus. Compared with both controls and MobFD cases, FixFD patients showed a severe disruption of WM architecture along the corpus callous, corticospinal tract, anterior thalamic radiations, and major long-range tracts bilaterally. This study showed different MRI patterns in two variants of FD. MobFD had alterations in GM structures crucial for sensorimotor processing, emotional, and cognitive control. On the other hand, FixFD patients were characterized by a global WM disconnection affecting main sensorimotor and emotional control circuits. These findings may have important implications in understanding the neural substrates underlying different phenotypic FD expression levels.

Predisposing Risk Factors for Functional Limb Weakness: A Case-Control Study

OBJECTIVE

Functional limb weakness is a common symptom of functional neurological disorder. Few controlled studies have examined possible predisposing factors to determine their specificity for this symptom.

METHODS

In this prospective case-control study, patients with functional limb weakness (<2 years duration, N=107) were compared with a control group (comprising patients with weakness attributable to neurological disease, N=46, and healthy individuals, N=39). A structured clinical interview and questionnaires assessed potential predisposing factors, including family structure and childhood abuse and neglect (Childhood Trauma Questionnaire [CTQ]), personality traits (NEO Five-Factor Inventory), medical and surgical comorbidity, and exposure to a symptom model.

RESULTS

The patients with functional limb weakness and the control subjects were similar in gender and age. Self-reported childhood sexual abuse (15% versus 5%, p<0.01), and physical abuse (18% versus 7%, p<0.01; CTQ "moderate or above") were more common in the functional limb weakness group, although the absolute frequency was lower than anticipated. In the functional limb weakness group, there were modest differences in two personality traits, compared with the control group: higher neuroticism (p=0.02) and lower openness (p=0.01). Medical comorbidity, including appendectomy (33% versus 5%), irritable bowel syndrome (36% versus 18%), and chronic back pain (40% versus 16%), was more frequent in the functional limb weakness group. There were no differences in birth order or exposure to a symptom model.

CONCLUSIONS

Medical and surgical comorbidity and adverse childhood experience are risk factors, but not essential, for the development of functional limb weakness. However, evidence for personality traits or exposure to a symptom model is less robust.

Should we routinely assess psychological morbidities in idiopathic lower urinary tract dysfunction: ICI-RS 2019?

AIMS

Psychological morbidities play a major role in idiopathic lower urinary tract dysfunction (iLUTD). The aim of the Think Tank (TT) was to discuss the relevance of psychological morbidities in idiopathic LUTD over the life span, including overactive bladder (OAB) or dysfunctional voiding (DV) and methods of assessment.

METHODS

The paper is based on a selective review of the literature and in-depth discussions, leading to research recommendations regarding the assessment of psychological morbidities in iLUTD on children and adults held during the TT of the International Consultation on Incontinence Research Society in 2019.

RESULTS

Psychological comorbidities affect the health behaviors and treatment outcomes in patients with iLUTD. Both clinically relevant comorbid mental disorders, as well as subclinical psychological symptoms have a major impact and negatively influence incontinence treatment. Research is needed to elucidate mechanisms underlying iLUTD and psychological comorbidities. Clinical studies are needed to determine how perception generation and cognition impacts on the relationship of urinary perceptions, symptoms, and objective urodynamic function. Due to high psychological comorbidity rates, screening with validated, generic questionnaires for emotional and behavioral disorders in children with nocturnal enuresis, daytime urinary incontinence, and fecal incontinence is recommended. Brief screening is recommended for all adults with iLUTD, especially with OAB and DV, who are refractory to treatment.

CONCLUSIONS

Due to the high rate and relevance in clinical practice, screening for psychological comorbidities is recommended for all age groups. The research recommendations of this TT may be followed to improve the assessment of psychological morbidities in iLUTD.

[Personality traits of Japanese patients with focal dystonia-Variable classification by affected body part and occupation]

We administered the Revised Neo Personality Inventory (NEO-PI-R) to 92 Japanese patients with focal dystonia and analyzed the relation of their personality traits, affected body parts, and occupations using a decision tree method. Results show that participants' personality traits were related to their occupation rather than the body part. Occupational dystonia patients including musicians exhibited neurotic tendencies and a high level of anxiety. Moreover, patients with occupational upper limb dystonia had realistic thinking patterns. Patients with musicians' dystonia were open about their emotional experiences: both positive and negative.

Shared demographics and comorbidities in different functional motor disorders

INTRODUCTION

Functional motor disorders are often delineated according to the dominant motor symptom. In a large cohort, we aimed to find if there were differences in demographics, mode of onset, pain, fatigue, depression and anxiety and levels of physical functioning, quality of life and social adjustment between patients with different dominant motor symptoms.

METHODS

Baseline data from the Self-Help and Education on the Internet for Functional Motor Disorders Trial was used. Patients were divided into dominant motor symptom groups based on the diagnosis of the referring neurologist. Data on the above topics were collected by means of an online questionnaire and compared between groups using parametric and nonparametric statistics.

RESULTS

In 160 patients a dominant motor symptom could be determined, 31 had tremor, 45 myoclonus, 23 dystonia, 30 paresis, 31 gait disorder. No statistical differences between groups were detected for demographics, mode of onset and severity of pain, fatigue, depression and anxiety. Physical functioning was worse in the gait disorder group (median 20, IQR 25) compared to tremor (50 (55), p = 0.002) and myoclonus (50 (52), p = 0.001). Work and social adjustment was less impaired in the myoclonus group (median 20, IQR 18) compared to gait disorder (median 30, IQR18, p < 0.001) and paresis (28, IQR 10, p = 0.001). Self-report showed large overlap in motor symptoms.

CONCLUSION

No differences were detected between groups of functional motor symptoms, regarding demographics, mode of onset, depression, anxiety, pain and fatigue. The large overlap in symptoms contributes to the hypothesis of shared underlying mechanisms of functional motor disorders.