Service-based survey of dystonia in Munich

We performed a service-based epidemiological study of dystonia in Munich, Germany. Due to favourable referral and treatment patterns in the Munich area, we could provide confident data from dystonia patients seeking botulinum toxin treatment. A total of 230 patients were ascertained, of whom 188 had primary dystonia. Point prevalence ratios were estimated to be 10.1 (95% confidence interval 8.4-11.9) per 100,000 for focal and 0.3 (0.0-0.6) for generalised primary dystonia. The most common focal primary dystonias were cervical dystonia with 5.4 (4.2-6.7) and essential blepharospasm with 3.1 (2.1-4.1) per 100,000 followed by laryngeal dystonia (spasmodic dysphonia) with 1.0 (0.4-1.5) per 100,000. Copyright (C) 2002 S. Karger AG, Base

The V471A polymorphism in autophagy-related gene ATG7 modifies age at onset specifically in Italian Huntington disease patients

The cause of Huntington disease (HD) is a polyglutamine repeat expansion of more than 36 units in the huntingtin protein, which is inversely correlated with the age at onset of the disease. However, additional genetic factors are believed to modify the course and the age at onset of HD. Recently, we identified the V471A polymorphism in the autophagy-related gene ATG7, a key component of the autophagy pathway that plays an important role in HD pathogenesis, to be associated with the age at onset in a large group of European Huntington disease patients. To confirm this association in a second independent patient cohort, we analysed the ATG7 V471A polymorphism in additional 1,464 European HD patients of the “REGISTRY” cohort from the European Huntington Disease Network (EHDN). In the entire REGISTRY cohort we could not confirm a modifying effect of the ATG7 V471A polymorphism. However, analysing a modifying effect of ATG7 in these REGISTRY patients and in patients of our previous HD cohort according to their ethnic origin, we identified a significant effect of the ATG7 V471A polymorphism on the HD age at onset only in the Italian population (327 patients). In these Italian patients, the polymorphism is associated with a 6-years earlier disease onset and thus seems to have an aggravating effect. We could specify the role of ATG7 as a genetic modifier for HD particularly in the Italian population. This result affirms the modifying influence of the autophagic pathway on the course of HD, but also suggests population-specific modifying mechanisms in HD pathogenesis

Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

Non-motor Symptoms Questionnaire and Scale for Parkinson's disease

Idiopathic Parkinson's disease (PD) is a multisytem degenerative disorder. In addition to motor symptoms such as akinesia, rigidity and tremor, various non-motor symptoms occur, which are still insufficiently diagnosed. Moreover, the frequently used scales and scores do not adequately detect these non-motor symptoms. The Non-motor Symptoms Questionnaire (NMSQuest) is an established self-completed patient questionnaire with 30 qualitative questions covering all important non-motor symptoms of PD. The Non-motor Symptoms Scale (NMSScale) is a grade rating scale for estimating the frequency and severity of non-motor symptoms in PD. Since there are only original English versions of both questionnaires available, self-translated versions were frequently used or the questionnaires were not used at all in native German patients. We used international guidelines for cross-cultural adaptation of questionnaires to provide standard versions of both non-motor symptoms questionnaires in the German language

Autosomal-dominant GTPCH1-deficient DRD: Clinical characteristics and long-term outcome of 34 patients

International audienceAn autosomal dominantly inherited defect in the GCH1 gene that encodes guanosine triphosphate cyclohydrolase 1 (GTPCH1) is the most common cause of dopa-responsive dystonia (DRD). A classic phenotype of young-onset lower limb dystonia, diurnal fluctuations, and excellent response to levodopa has been well recognized in association with GCH1 mutations, and rare atypical presentations have been reported. However, a number of clinical issues remain unresolved including phenotypic variability, long-term response to levodopa and associated non-motor symptoms, and there are limited data on long-term follow up of genetically proven cases. We present a detailed clinical evaluation of 34 patients (19 women, 15 men) with confirmed mutations in the GCH1 gene. We found that the classic phenotype was most frequent (n=23), with female predominance (F:M=16:7), and early onset (mean 4.5 years) with involvement of legs. However, a surprisingly large number of patients developed craniocervical dystonia, with spasmodic dysphonia being the predominant symptom in two subjects. A subset of patients, mainly men, presented with either a young-onset (mean 6.8 years) mild DRD variant not requiring treatment (n=4), or with an adult-onset (mean 37 years) Parkinson's disease-like phenotype (n=4). Two siblings were severely affected with early hypotonia and delay in motor development, associated with compound heterozygous GCH1 gene mutations. We also describe a number of supplementary features including restless legs-like symptoms, influence of female sex hormones, predominance of tremor or parkinsonism in adult-onset cases, initial reverse reaction to levodopa, recurrent episodes of depressive disorder, and specific levodopa-resistant symptoms (writer's cramp, dysphonia, truncal dystonia). We report that levodopa was used effectively and safely in 20 pregnancies, and did not cause any foetal abnormalities

Task-specific training in Huntington disease: a randomized controlled feasibility trial.

BACKGROUND: Task-specific training may be a suitable intervention to address mobility limitations in people with Huntington disease (HD). OBJECTIVE: The aim of this study was to assess the feasibility and safety of goal-directed, task-specific mobility training for individuals with mid-stage HD. DESIGN: This study was a randomized, blinded, feasibility trial; participants were randomly assigned to control (usual care) and intervention groups. SETTING: This multisite study was conducted in 6 sites in the United Kingdom. PATIENTS: Thirty individuals with mid-stage HD (13 men, 17 women; mean age=57.0 years, SD=10.1) were enrolled and randomly assigned to study groups. INTERVENTION: Task-specific training was conducted by physical therapists in participants' homes, focusing on walking, sit-to-stand transfers, and standing, twice a week for 8 weeks. Goal attainment scaling was used to individualize the intervention and monitor achievement of personal goals. MEASUREMENTS: Adherence and adverse events were recorded. Adjusted between-group comparisons on standardized outcome measures were conducted at 8 and 16 weeks to determine effect sizes. RESULTS: Loss to follow-up was minimal (n=2); adherence in the intervention group was excellent (96.9%). Ninety-two percent of goals were achieved at the end of the intervention; 46% of the participants achieved much better than expected outcomes. Effect sizes on all measures were small. LIMITATIONS: Measurements of walking endurance were lacking. CONCLUSIONS: The safety of and excellent adherence to a home-based, task-specific training program, in which most participants exceeded goal expectations, are encouraging given the range of motivational, behavioral, and mobility issues in people with HD. The design of the intervention in terms of frequency (dose), intensity (aerobic versus anaerobic), and specificity (focused training on individual tasks) may not have been sufficient to elicit any systematic effects. Thus, a larger-scale trial of this specific intervention does not seem warranted

Urinary Neopterin and Phenylalanine Loading Test as Tools for the Biochemical Diagnosis of Segawa Disease

Background. The diagnosis of autosomal dominant GTP-cyclohydrolase deficiency relies on the examination of the GCH1 gene and/or pterins and neurotransmitters in CSF. The aim of the study was to assess the diagnostic value, if any, of pterins in urine and blood phenylalanine (Phe) and tyrosine (Tyr) under oral Phe loading test. Methods. We report on two new pedigrees with four symptomatic and four asymptomatic carriers whose pattern of urinary pterins and blood Phe/Tyr ratio under oral Phe loading pointed to GTP-cyclohydrolase deficiency. The study was then extended to 3 further patients and 90 controls. The diagnostic specificity and sensitivity of these metabolic markers were analysed by backwards logistic analysis. Results. Two genetic alterations segregated alternatively in Family 1 (c.631-632 del AT and c.671A > G), while exon 1 deletion was transmitted along three generations in Family 2. Neopterin and biopterin concentrations in urine clustered differently in controls under and over the age of 15. Therefore patients and controls were sub grouped according to this age. Neopterin was significantly reduced in GCH1 mutated subjects younger than 15, and both neopterin and biopterin in those older than 15. Moreover, the Phe/Tyr ratios at the second and third hour were both significantly higher in patients than in controls. Backwards logistic regression demonstrated the high diagnostic sensitivity and specificity of combined values of neopterin concentration and Phe/Tyr ratio at the second hour. Conclusions. Pterins in urine and Phe loading test are non-invasive and reliable tools for the biochemical diagnosis of GTP-cyclohydrolase deficiency