Risk factors for idiopathic dystonia in Queensland, Australia

Do cerebrovascular risk factors impact the clinical expression of idiopathic isolated adult-onset dystonia?

BACKGROUND

Although acquired dystonia may develop following ischaemic/haemorrhagic stroke, the relationship between cerebrovascular disease and idiopathic dystonia has been poorly investigated. This cross sectional study aimed at evaluating the impact of cerebrovascular risk factors on the clinical expression of idiopathic adult onset dystonia (IAOD), with reference to dystonia localization and dystonia-associated features.

METHODS

Data were obtained from the Italian Dystonia Registry. Patients with IAOD were stratified into two groups according to the presence of diabetes mellitus and/or arterial hypertension and/or dyslipidemia and/or heart disease. The two groups were compared for demographic features, dystonia phenotype, and dystonia-associated features (sensory trick, tremor, eye symptoms in blepharospasm, and neck pain in cervical dystonia).

RESULTS

A total of 1108 patients participated into the study. Patients who reported one cerebrovascular factor or more (n = 555) had higher age and longer disease duration than patients who did not. On multivariable logistic regression analysis, blepharospasm was the only localization, and sensory trick was the only dystonia-associated feature that was significantly associated with cerebrovascular risk factors. Linear regression analysis showed that the strength of the association between cerebrovascular factors and blepharospasm/sensory trick increased with increasing the number of cerebrovascular factors per patient.

CONCLUSIONS

Results of the present study showed that cerebrovascular risk factors may be associated with specific features of IAOD that is development of blepharospasm and sensory trick. Further studies are needed to better understand the meaning and the mechanisms underlying this association.

Second hit hypothesis in dystonia: Dysfunctional cross talk between neuroplasticity and environment?

One of the great mysteries in dystonia pathophysiology is the role of environmental factors in disease onset and development. Progress has been made in defining the genetic components of dystonic syndromes, still the mechanisms behind the discrepant relationship between dystonic genotype and phenotype remain largely unclear. Within this review, the preclinical and clinical evidence for environmental stressors as disease modifiers in dystonia pathogenesis are summarized and critically evaluated. The potential role of extragenetic factors is discussed in monogenic as well as adult-onset isolated dystonia. The available clinical evidence for a "second hit" is analyzed in light of the reduced penetrance of monogenic dystonic syndromes and put into context with evidence from animal and cellular models. The contradictory studies on adult-onset dystonia are discussed in detail and backed up by evidence from animal models. Taken together, there is clear evidence of a gene-environment interaction in dystonia, which should be considered in the continued quest to unravel dystonia pathophysiology.

The prevalence of anxiety in adult-onset isolated dystonia: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Clinically relevant anxiety and anxiety disorders are commonly associated with adult-onset isolated dystonia, contributing substantially to quality-of-life impairment in patients with this movement disorder. However, the prevalence of anxiety symptoms and disorders in adult-onset isolated dystonia remains unclear. We aimed to conduct a systematic review and meta-analysis of the prevalence of anxiety symptoms/disorders in adult-onset isolated dystonia.

METHODS

Studies reporting the prevalence of anxiety disorders determined through diagnostic interviews or from clinically relevant anxiety symptoms detected with rating scales were identified in three databases (MEDLINE, EMBASE and PsycINFO). The gray literature was also examined to detect studies not captured through the search strategy.

RESULTS

The search strategy yielded 6535 citations; 34 studies met the inclusion criteria. The overall prevalence of clinically relevant anxiety symptoms and anxiety disorders for cervical dystonia was 40% (95% confidence interval [CI] 20% to 60%); for studies examining cranial dystonia it was 25% (95% CI 21% to 30%); for studies exploring mixed populations of adult-onset isolated dystonia it was 33.3% (95% CI 22% to 43%), 26% (95% CI 12% to 40%) for laryngeal dystonia, and 32% (95% CI 21% to 43%) for upper limb dystonia. Social phobia was the most prevalent anxiety disorder across the different forms of adult-onset isolated dystonia. Between-study statistical heterogeneity was high for most prevalence estimates.

CONCLUSIONS

Clinically relevant anxiety and anxiety disorders are common across all forms of adult-onset isolated dystonia. New research avenues should explore and plan the development of pathways of care targeting these important non-motor features.

The Dutch Yips Study: Results of a Survey Among Golfers

Background:

The yips in golf is currently regarded as a task-specific movement disorder, with variable phenomenology and of unclear etiology. There is some overlap with task-specific dystonia (TSD), which has also been reported in other sports. The objective was to further characterize the yips in terms of its prevalence and related factors.

Methods:

Recreational golfers from one of the larger golf clubs in the Netherlands aged 18 years or older, filled in an anonymous, web-based questionnaire with items on demographic, medical and lifestyle factors, specific yips-relevant items, as well as fanaticism, familial presence of yips, obsessive-compulsive traits, and a dystonia questionnaire.

Results:

In total, 234 golfers (26%) completed the questionnaire, among whom 52 (22%, 95% CI: 17–28%) reported to suffer from the yips. In comparison to their non-yips counterparts, the yips group was characterized by a larger proportion of men, more current or past smoking, better golf skills, longer history of playing golf, and more familial yips occurrence.

Discussion:

Golfer’s self-reported yips may be very frequent in a group of responding amateur golfers and associated factors seems to include male gender, current or past smoking, extensive golf experience and skills, and a positive family history of the yips. Further work to better understand the origin and nature of the yips is needed.

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.

A metabolomic study of cervical dystonia

INTRODUCTION

Cervical dystonia is the most common of the adult-onset focal dystonias. Most cases are idiopathic. The current view is that cervical dystonia may be caused by some combination of genetic and environmental factors. Genetic contributions have been studied extensively, but there are few studies of other factors. We conducted an exploratory metabolomics analysis of cervical dystonia to identify potentially abnormal metabolites or altered biological pathways.

METHODS

Plasma samples from 100 cases with idiopathic cervical dystonia and 100 controls were compared using liquid chromatography coupled with mass spectrometry-based metabolomics.

RESULTS

A total of 7346 metabolic features remained after quality control, and up to 289 demonstrated significant differences between cases and controls, depending on statistical criteria chosen. Pathway analysis revealed 9 biological processes to be significantly associated at p < 0.05, 5 pathways were related to carbohydrate metabolism, 3 pathways were related to lipid metabolism.

CONCLUSION

This is the first large scale metabolomics study for any type of dystonia. The results may provide potential novel insights into the biology of cervical dystonia.

A survey of lifestyle factors in dystonia

BACKGROUND

Knowledge about what causes dystonia is highly incomplete, especially about the impact of nongenetic factors.

AIMS OF THE STUDY

This cross-sectional survey-based explorative study examined different nongenetic factors in patients with dystonia.

METHODS

Information from both medical records and a questionnaire was collected. In total, 220 patients with dystonia were identified, of which 51 participated in the survey.

RESULTS

Women had a higher prevalence for cervical dystonia than men. Smoking was approximately twice as common in our studied population compared to the general Swedish population. Significantly more men than women met the criteria for low level of physical activity, yet the proportion of missing data was high in this category.

CONCLUSIONS

Conclusions on causality cannot be drawn in this preliminary study, further research is encouraged regarding the link between smoking and dystonia.

Peripheral trauma and risk of dystonia: What are the evidences and potential co-risk factors from a population insurance database?

Background

Dystonia is a neurological syndrome typically resulting in abnormal postures.

Objectives

We tested the role of physical injury as potential risk factor for development of dystonia using The National Health Insurance Research Database of Taiwan.

Methods

We identified 65704 people who were coded in the database as having had peripheral traumatic injuries (ICD-9-CM 807–848 and 860–959) in the year 2000. Patients with traumatic brain or spine injuries were excluded from analysis. We matched them using purposive sampling with 65704 people in the database who had not suffered peripheral trauma. We looked then at the incidence of dystonia occurring at least 1 year from the date of the peripheral trauma until 2011. Psychiatric symptoms (depression and anxiety) and sleeps difficulties have been investigated as potential covariates.

Results

We found 189 patients with dystonia (0.28%) in the trauma group, and 52 patients with dystonia (0.08%) in the non-trauma group. Trauma was independently associated with dystonia (adjusted HR = 3.12, 95% CI = 2.30–4.24). The incidence density of dystonia in the trauma group was 2.27 per 10000 person-years, while it was 0.71 per 10000 person-years in the non-trauma group Beyond the peripheral trauma, other variables associated to the incidence of dystonia included female sex, aged 40 years and above, depression and sleep disorders.

Conclusion

These data from a large population dataset support traumatic injury as a risk factor for the development of dystonia.

Understanding dystonia: diagnostic issues and how to overcome them

ABSTRACT The diagnosis and treatment of dystonia are challenging. This is likely due to gaps in the complete understanding of its pathophysiology, lack of animal models for translational studies, absence of a consistent pathological substrate and highly variable phenotypes and genotypes. The aim of this review article is to provide an overview of the clinical, neurophysiological and genetic features of dystonia that can help in the identification of this movement disorder, as well as in the differential diagnosis of the main forms of genetic dystonia. The variation of penetrance, age of onset, and topographic distribution of the disease in carriers of the same genetic mutation indicates that other factors – either genetic or environmental – might be involved in the development of symptoms. The growing knowledge of cell dysfunction in mutants may give insights into more effective therapeutic targets.