Does sex influence the natural history of idiopathic adult-onset dystonia?

BACKGROUND: Several earlier studies showed a female predominance in idiopathic adult-onset dystonia (IAOD) affecting the craniocervical area and a male preponderance in limb dystonia. However, sex-related differences may result from bias inherent to study design. Moreover, information is lacking on whether sex-related differences exist in expressing other dystonia-associated features and dystonia spread. OBJECTIVE: To provide accurate information on the relationship between sex differences, motor phenomenology, dystonia-associated features and the natural history of IAOD. METHODS: Data of 1701 patients with IAOD from the Italian Dystonia Registry were analysed. RESULTS: Women predominated over men in blepharospasm, oromandibular, laryngeal and cervical dystonia; the sex ratio was reversed in task-specific upper limb dystonia; and no clear sex difference emerged in non-task-specific upper limb dystonia and lower limb dystonia. This pattern was present at disease onset and the last examination. Women and men did not significantly differ for several dystonia-associated features and tendency to spread. In women and men, the absolute number of individuals who developed dystonia tended to increase from 20 to 60 years and then declined. However, when we stratified by site of dystonia onset, different patterns of female-to-male ratio over time could be observed in the various forms of dystonia. CONCLUSIONS: Our findings provide novel evidence on sex as a key mediator of IAOD phenotype at disease onset. Age-related sexual dimorphism may result from the varying exposures to specific age-related and sex-related environmental risk factors interacting in a complex manner with biological factors such as hormonal sex factors.

Does thyroid diseases contribute to the natural history of idiopathic adult-onset dystonia? Data from the Italian Dystonia Registry.

A few earlier observations and recent controlled studies pointed to the possible contribution of thyroid diseases in idiopathic adult-onset dystonia (IAOD). The aim of this study was to investigate the association between thyroid status and clinical characteristics of IAOD, focusing on dystonia localization, spread, and associated features such as tremors and sensory tricks. Patients were identified from those included in the Italian Dystonia Registry, a multicentre dataset of patients with adult-onset dystonia. The study population included 1518 IAOD patients. Patients with hypothyroidism and hyperthyroidism were compared with those without any thyroid disease. In the 1518 IAOD patients, 167 patients (11%; 95% CI 9.5-12.6%) were diagnosed with hypothyroidism and 42 (2.8%; 95% CI 1.99-3.74) with hyperthyroidism. The three groups were comparable in age at dystonia onset, but there were more women than men in the groups with thyroid disease. Analysing the anatomical distribution of dystonia, more patients with blepharospasm were present in the hyperthyroidism group, but the difference did not reach statistical significance after the Bonferroni correction. The remaining dystonia-affected body sites were similarly distributed in the three groups, as did dystonia-associated features and spread. Our findings provided novel information indicating that the high rate of thyroid diseases is not specific for any specific dystonia subpopulation and does not appear to influence the natural history of the disease.

Diagnostic and therapeutic recommendations in adult dystonia: a joint document by the Italian Society of Neurology, the Italian Academy for the Study of Parkinson's Disease and Movement Disorders, and the Italian Network on Botulinum Toxin.

The diagnostic framework and the therapeutic management of patients with adult dystonia can represent a challenge for clinical neurologists. The objective of the present paper is to delineate diagnostic and therapeutic recommendations for dystonia provided by a panel of Italian experts afferent to the Italian Society of Neurology, the Italian Academy for the Study of Parkinson's Disease and Movement Disorders, and the Italian Network on Botulinum Toxin. We first discuss the clinical approach and the instrumental assessment useful for diagnostic purpose. Then, we analyze the pharmacological, surgical, and rehabilitative therapeutic options for adult dystonia. Finally, we propose a hospital-territory network model for adult dystonia management.

Pimozide and pancreatic cancer in diabetic chorea: a case report.

PURPOSE/AIM: Diabetic chorea is a rare movement disorder associated with diabetes mellitus. We report the case of a patient that benefited from pimozide and died of pancreatic cancer. CASE REPORT: A 70-year-old woman presented with pollakiuria and involuntary movements of left limbs since three months. Laboratory tests revealed high serum levels of glycemia and glycated haemoglobin. She was admitted to internal medicine department and discharged one week later: insulin was administered with normalization of blood glucose levels and the involuntary movements gradually disappeared. Three weeks later she was admitted to neurological department due to the recurrence of the involuntary movements. Glycemia and other routine laboratory tests were normal. Neurological examination showed choreic movements involving left limbs. MRI showed a hyperintensity on T1- and T2-weighted sequences of right putamen and caudate nucleus head. Haloperidol was administered without improvement, it was successively substituted with tetrabenazine and the patient was discharged with an unvaried clinical picture. Two months later tetrabenazine was discontinued because of inefficacy and pimozide was started. The choreic movements considerably diminished after few days. Four months later, a pancreatic cancer was diagnosed and the patient died in the same month. CONCLUSION: Clinical and radiological features were suggestive of diabetic chorea. Our patient benefited exclusively from pimozide, it could be reasonable to use pimozide in resistant form and also propose it as first choice treatment. Another important element is the diagnosis of pancreatic cancer some months after chorea onset: a causal link could exist.

The contribution of the Italian residents in neurology to the COVID-19 crisis: admirable generosity but neurological training remains their priority.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has severely impacted the Italian healthcare system, underscoring a dramatic shortage of specialized doctors in many disciplines. The situation affected the activity of the residents in neurology, who were also offered the possibility of being formally hired before their training completion. AIMS: (1) To showcase examples of clinical and research activity of residents in neurology during the COVID-19 pandemic in Italy and (2) to illustrate the point of view of Italian residents in neurology about the possibility of being hired before the completion of their residency program. RESULTS: Real-life reports from several areas in Lombardia-one of the Italian regions more affected by COVID-19-show that residents in neurology gave an outstanding demonstration of generosity, collaboration, reliability, and adaptation to the changing environment, while continuing their clinical training and research activities. A very small minority of the residents participated in the dedicated selections for being hired before completion of their training program. The large majority of them prioritized their training over the option of earlier employment. CONCLUSIONS: Italian residents in neurology generously contributed to the healthcare management of the COVID-19 pandemic in many ways, while remaining determined to pursue their training. Neurology is a rapidly evolving clinical field due to continuous diagnostic and therapeutic progress. Stakeholders need to listen to the strong message conveyed by our residents in neurology and endeavor to provide them with the most adequate training, to ensure high quality of care and excellence in research in the future.

Idiopathic Non-task-Specific Upper Limb Dystonia, a Neglected Form of Dystonia.

OBJECTIVE: The objective of this study was to describe the clinical and demographic features of idiopathic non-task-specific upper limb dystonia compared with the task-specific form. METHODS: In this retrospective study, adult patients with idiopathic upper limb dystonia, either focal or as part of a segmental/multifocal dystonia, from the Italian Dystonia Registry were enrolled. In patients with focal upper limb dystonia, dystonia spread was estimated by survival analysis. RESULTS: Of the 1522 patients with idiopathic adult-onset dystonia included in the Italian Dystonia Registry, we identified 182 patients with upper limb dystonia. Non-task-specific dystonia was present in 61.5% of enrolled cases. Women predominated among non-task-specific patients, whereas men predominated in the task-specific group. Peak age of upper limb dystonia onset was in the sixth decade in the non-task-specific group and in the fourth decade in the task-specific group. In both groups, upper limb dystonia started as focal dystonia or as part of a segmental dystonia. Segmental onset was more frequent among non-task-specific patients, whereas focal onset predominated among task-specific patients. Dystonic action tremor was more frequent among non-task-specific patients. No significant differences between groups emerged in terms of sensory trick frequency, rest tremor, or family history of dystonia. In patients with focal upper limb dystonia, dystonia spread was greater in the non-task-specific group. CONCLUSION: Novel information on upper limb dystonia patients suggests that non-task-specific and task-specific upper limb dystonia have different demographic and clinical features. However, it remains to be determined whether these differences also reflect pathophysiological differences. © 2020 International Parkinson and Movement Disorder Society.

Demographic and clinical determinants of neck pain in idiopathic cervical dystonia.

Cervical dystonia is associated with neck pain in a significant proportion of cases, but the mechanisms underlying pain are largely unknown. In this exploratory study, we compared demographic and clinical variables in cervical dystonia patients with and without neck pain from the Italian Dystonia Registry. Univariable and multivariable logistic regression analysis indicated a higher frequency of sensory trick and a lower educational level among patients with pain.

Expert recommendations for diagnosing cervical, oromandibular, and limb dystonia.

BACKGROUND: Diagnosis of focal dystonia is based on clinical grounds and is therefore open to bias. To date, diagnostic guidelines have been only proposed for blepharospasm and laryngeal dystonia. To provide practical guidance for clinicians with less expertise in dystonia, a group of Italian Movement Disorder experts formulated clinical diagnostic recommendations for cervical, oromandibular, and limb dystonia. METHODS: A panel of four neurologists generated a list of clinical items related to the motor phenomenology of the examined focal dystonias and a list of clinical features characterizing neurological/non-neurological conditions mimicking dystonia. Thereafter, ten additional expert neurologists assessed the diagnostic relevance of the selected features and the content validity ratio was calculated. The clinical features reaching a content validity ratio > 0.5 contributed to the final recommendations. RESULTS: The recommendations retained patterned and repetitive movements/postures as the core feature of dystonia in different body parts. If present, a sensory trick confirmed diagnosis of dystonia. In the patients who did not manifest sensory trick, active exclusion of clinical features related to conditions mimicking dystonia (features that would be expected to be absent in dystonia) would be necessary for dystonia to be diagnosed. DISCUSSION: Although reliability, sensitivity, and specificity of the recommendations are yet to be demonstrated, information from the present study would hopefully facilitate diagnostic approach to focal dystonias in the clinical practice and would be the basis for future validated diagnostic guidelines.

Pain processing in functional and idiopathic dystonia: An exploratory study.

BACKGROUND: Pain is often experienced by patients with functional dystonia and idiopathic cervical dystonia and is likely to be determined by different neural mechanisms. OBJECTIVE: In this exploratory study, we tested the sensory-discriminative and cognitive-emotional component of pain in patients with functional and idiopathic dystonia. METHODS: Ten patients with idiopathic cervical dystonia, 12 patients with functional dystonia, and 16 age- and sex-matched healthy controls underwent psychophysical testing of tactile and pain thresholds and pain tolerance. We delivered electrical pulses of increasing intensity to the index finger of each hand and the halluces of each foot. Pain threshold and pain tolerance were respectively defined as the (1) intensity at which sensation changed from unpainful to faintly painful and (2) intensity at which painful sensation was intolerable. RESULTS: No differences were found between the three groups for tactile and pain thresholds assessed in hands and feet. Pain tolerance was significantly increased in all body regions only in functional dystonia. Patients with continuous functional dystonia had higher pain tolerance compared to subjects with paroxysmal functional dystonia and idiopathic cervical dystonia. There was no correlation between pain tolerance and pain scores, depression, anxiety, disease duration, and motor disability in both groups. CONCLUSIONS: Patients with functional dystonia have a dissociation between the sensory-discriminative and cognitive-emotional components of pain, as revealed by normal pain thresholds and increased pain tolerance. Abnormal connectivity between the motor and limbic systems might account for abnormal pain processing in functional dystonia. © 2018 International Parkinson and Movement Disorder Society.

Biased Visuospatial Attention in Cervical Dystonia.

OBJECTIVES: There is increasing evidence of non-motor, sensory symptoms, mainly involving the spatial domain, in cervical dystonia (CD). These manifestations are likely driven by dysfunctional overactivity of the parietal cortex during the execution of a sensory task. Few studies also suggest the possibility that visuospatial attention might be specifically affected in patients with CD. Therefore, we asked whether non-motor manifestations in CD might also comprise impairment of higher level visuospatial processing. METHODS: To this end, we investigated visuospatial attention in 23 CD patients and 12 matched healthy controls (for age, gender, education, and ocular dominance). The patients were identified according to the dystonia pattern type (laterocollis vs. torticollis). Overall, participants were right-handers, and the majority of them was right-eye dominant. Visuospatial attention was assessed using a line bisection task. Participants were asked to bisect horizontal lines, using their right or left hand. RESULTS: Participants bisected more to the left of true center when using their left hand to perform the task than when using their right hand. However, overall, torticollis patients produced a significantly greater leftward deviation than controls. CONCLUSIONS: These data are consistent with preliminary findings suggesting the presence of biased spatial attention in patients with idiopathic cervical dystonia. The presence of an attentional bias in patients with torticollis seem to indicate that alterations of attentional circuits might be implicated in the pathophysiology of this type of CD. (JINS, 2018, 24, 23-32).

Normal sensorimotor plasticity in complex regional pain syndrome with fixed posture of the hand.

BACKGROUND: Movement disorders associated with complex regional pain syndrome type I have been a subject of controversy over the last 10 years regarding their nature and pathophysiology, with an intense debate about the functional (psychogenic) nature of this disorder. The aim of this study was to test sensorimotor plasticity and cortical excitability in patients with complex regional pain syndrome type I who developed a fixed posture of the hand. METHODS: Ten patients with complex regional pain syndrome type I in the right upper limb and a fixed posture of the hand (disease duration less than 24 months) and 10 age-matched healthy subjects were enrolled. The following parameters of corticospinal excitability were recorded from the abductor pollicis brevis muscle of both hands by transcranial magnetic stimulation: resting and active motor thresholds, short-interval intracortical inhibition and facilitation, cortical silent period, and short- and long-latency afferent inhibition. Sensorimotor plasticity was tested using the paired associative stimulation protocol. RESULTS: Short-interval intracortical inhibition and long-latency afferent inhibition were reduced only in the affected right hand of patients compared with control subjects. Sensorimotor plasticity was comparable to normal subjects, with a preserved topographic specificity. CONCLUSIONS: Our data support the view that motor disorder in complex regional pain syndrome type I is not associated with abnormal sensorimotor plasticity, and it shares pathophysiological abnormalities with functional (psychogenic) dystonia rather than with idiopathic dystonia. © 2016 International Parkinson and Movement Disorder Society.

A local signature of LTP-like plasticity induced by repetitive paired associative stimulation.

Repetitive paired associative stimulation (rPAS) repeatedly pairs electrical nerve stimulation (ENS) with transcranial magnetic stimulation (TMS) of the contralateral motor hand area (M1) at 5 Hz frequency. So far, there are only few studies concerning the effects of PAS on the modulation of EEG power. Hence, aim of the present study was to investigate rPAS long term after-effects on cortical excitability looking at EEG power spectra. In four experimental sessions, separated by 2 weeks interval, 12 awake subjects received rPAS of the right median nerve and left M1 at a fixed interval (ISI) of 25 ms (real condition), 5 Hz-TMS on left M1, 5 Hz-ENS, of the right median nerve, and rPAS with changing ISI (sham condition). We measured peak-to-peak MEP amplitude, evoked from the target muscle (right abductor pollicis brevis muscle) at rest and the absolute power (POW) in four frequency bands: α (8-12 Hz), ß (13-30), θ (4-7) and δ (1-3), under rest conditions. All these parameters were evaluated in three detection blocks: baseline, immediately after and after 30' from the end of the conditioning protocol. Real rPAS induced a long-lasting homotopic cortical excitability modulation, as indexed by MEP amplitude increase, that was paralleled by a long-lasting reduction of α/ß-POW and by a widespread θ-δ-POW modulation. rPAS applied over the sensory-motor cortex induced an LTP-like plasticity, as indexed by a robust reduction in the α/ß POW positively correlated with the MEP amplitude increase. rPAS25ms may be a useful tool for motor neurorehabilitation promoting a sensory-motor coupling within ß oscillations.

Cortical plasticity in patients with Parkinson's disease a window for therapeutic non-invasive neuromodulation.

Several evidences in animal models have consistently an alteration of cortico-striatal plasticity, which is related to the degeneration of the substantia nigra. An alteration of plasticity have also been reported in humans by recording evoked field potentials in the substantia nigra pars reticulata of PD patients undergoing subthalamic nucleus (STN) stimulation where high-frequency (HF) in the OFF state did not induce a lasting change in field potential amplitude in the substantia nigra. In addition protocols of non-invasive brain stimulation, such as paired associative stimulation (PAS) and theta-burst stimulation (TBS), can be used to investigate cortical plasticity of the human primary motor cortex. Despite data reported in literature are apparently controversial with some studies showing a reduced or increased or even normal LTP and LTD like plasticity, recent evidences suggest the hypothesis that these different pat- terns of cortical plasticity likely depend on the stage of the disease and on the concomitant administration of L-DOPA. The current review will provide an up-to-date of these issues on cortical plasticity in PD discussing the clinical implications in rehabilitation. In addition in the last section we will review the state of art of non invasive neuro- modulation as adjuvant treatment in the advanced stage of the disease.

Tremor in primary adult-onset dystonia: prevalence and associated clinical features.

OBJECTIVE: To investigate the frequency and the main clinical features of tremor in primary adult-onset dystonia (PAOD). METHODS: This cross-sectional study was conducted on 429 patients with PAOD from eight Italian movement disorder centres. RESULTS: Of the 429 dystonic patients, 72 (16.7%) had tremor. Although sex and age at dystonia onset were similar in dystonic patients who had tremor and those who did not, patients who had tremor were affected more often by focal cervical dystonia and less often by focal blepharospasm. Dystonia had a greater tendency to spread in patients with tremor. According to the Movement Disorder Society Consensus Statement, tremor was classified as dystonic tremor (DT) in 43 patients and tremor associated with dystonia (TAWD) in 23 patients. Six patients had both types of tremor. Taking into account potential confounding by age at onset and body distribution of the corresponding dystonia type, all the clinical features in patients with DT and in those with TAWD were comparable except the tendency of dystonia to spread, which was greater in patients with DT. CONCLUSIONS: Tremor is a relatively common feature occurring in about 17% of patients with primary late-onset dystonia. The association between tremor and dystonia spread suggests that this form of tremor may be a dystonic manifestation. Similarities in phenotypic features of DT and TAWD predominated over differences, suggesting that the two forms of tremor may be manifestations of the same disease. Differences in gender and body distribution of tremor between patients with dystonia and tremor and those of patients with essential tremor also suggest that tremor in dystonia and essential tremor are different entities.

Phenotypic Variability in Acquired and Idiopathic Dystonia.

Background: To date, a few studies have systematically investigated differences in the clinical spectrum between acquired and idiopathic dystonias. Objectives: To compare demographic data and clinical features in patients with adult-onset acquired and idiopathic dystonias. Methods: Patients were identified from among those included in the Italian Dystonia Registry, a multicenter Italian dataset of patients with adult-onset dystonia. Study population included 116 patients with adult-onset acquired dystonia and 651 patients with isolated adult-onset idiopathic dystonia. Results: Comparison of acquired and idiopathic dystonia revealed differences in the body distribution of dystonia, with oromandibular dystonia, limb and trunk dystonia being more frequent in patients with acquired dystonia. The acquired dystonia group was also characterized by lower age at dystonia onset, greater tendency to spread, lower frequency of head tremor, sensory trick and eye symptoms, and similar frequency of neck pain associated with CD and family history of dystonia/tremor. Conclusions: The clinical phenomenology of dystonia may differ between acquired and idiopathic dystonia, particularly with regard to the body localization of dystonia and the tendency to spread. This dissimilarity raises the possibility of pathophysiological differences between etiologic categories.