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81 result(s) for "Reilmann, Ralf"
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Predictors of phenotypic progression and disease onset in premanifest and early-stage Huntington's disease in the TRACK-HD study: analysis of 36-month observational data
TRACK-HD is a multinational prospective observational study of Huntington's disease (HD) that examines clinical and biological findings of disease progression in individuals with premanifest HD (preHD) and early-stage HD. We aimed to describe phenotypic changes in these participants over 36 months and identify baseline predictors of progression. Individuals without HD but carrying the mutant huntingtin gene (classed as preHD-A if ≥10·8 years and preHD-B if <10·8 years from predicted onset), participants with early HD (classed as HD1 if they had a total functional capacity score of 11–13 and HD2 if they had a score of 7–10), and healthy control individuals were assessed at four study sites in the Netherlands, the UK, France, and Canada. We measured 36-month change for 3T MRI, clinical, cognitive, quantitative motor, and neuropsychiatric assessments and examined their prognostic value. We also assessed the relation between disease progression and the combined effect of CAG repeat length and age. All participants were analysed according to their baseline subgroups. Longitudinal results were analysed using a combination of repeated-measure weighted least squares models and, when examining risk of new diagnosis, survival analysis. At baseline, 366 participants were enrolled between Jan 17, and Aug 26, 2008, and of these 298 completed 36-month follow-up: 97 controls, 58 participants with preHD-A, 46 with preHD-B, 66 with HD1, and 31 with HD2. In the preHD-B group, several quantitative motor and cognitive tasks showed significantly increased rates of decline at 36 months, compared with controls, whereas few had at 24 months. Of the cognitive measures, the symbol digit modality test was especially sensitive (adjusted mean loss 4·11 points [95% CI 1·49–6·73] greater than controls; p=0·003). Among psychiatric indicators, apathy ratings specifically showed significant increases (0·34 points [95% CI 0·02–0·66] greater than controls; p=0·038). There was little evidence of reliable change in non-imaging measures in the preHD-A group, with the exception of the speeded tapping inter-tap interval (0·01 s [95% CI 0·01–0·02] longer than controls; p=0·0001). Several baseline imaging, quantitative motor, and cognitive measures had prognostic value, independent of age and CAG repeat length, for predicting subsequent clinical diagnosis in preHD. Of these, grey-matter volume and inter-tap interval were particularly sensitive (p=0·013 and 0·002, respectively). Longitudinal change in these two measures was also greater in participants with preHD who received a diagnosis of HD during the study compared with those who did not, after controlling for CAG repeat length and age-related risk (p=0·006 and 0·0003, respectively). In early HD, imaging, quantitative motor, and cognitive measures were predictive of decline in total functional capacity and tracked longitudinal change; also, neuropsychiatric changes consistent with frontostriatal pathological abnormalities were associated with this loss of functional capacity (problem behaviours assessment composite behaviour score p<0·0001). Age and CAG repeat length explained variance in longitudinal change of multimodal measures, with the effect more prominent in preHD. We have shown changes in several outcome measures in individuals with preHD over 36 months. These findings further our understanding of HD progression and have implications for clinical trial design. CHDI Foundation.
Gait variability as digital biomarker of disease severity in Huntington’s disease
Background Impaired gait plays an important role for quality of life in patients with Huntington’s disease (HD). Measuring objective gait parameters in HD might provide an unbiased assessment of motor deficits in order to determine potential beneficial effects of future treatments. Objective To objectively identify characteristic features of gait in HD patients using sensor-based gait analysis. Particularly, gait parameters were correlated to the Unified Huntington’s Disease Rating Scale, total motor score (TMS), and total functional capacity (TFC). Methods Patients with manifest HD at two German sites ( n  = 43) were included and clinically assessed during their annual ENROLL-HD visit. In addition, patients with HD and a cohort of age- and gender-matched controls performed a defined gait test (4 × 10 m walk). Gait patterns were recorded by inertial sensors attached to both shoes. Machine learning algorithms were applied to calculate spatio-temporal gait parameters and gait variability expressed as coefficient of variance (CV). Results Stride length (− 15%) and gait velocity (− 19%) were reduced, while stride (+ 7%) and stance time (+ 2%) were increased in patients with HD. However, parameters reflecting gait variability were substantially altered in HD patients (+ 17% stride length CV up to + 41% stride time CV with largest effect size) and showed strong correlations to TMS and TFC (0.416 ≤  r Sp  ≤ 0.690). Objective gait variability parameters correlated with disease stage based upon TFC. Conclusions Sensor-based gait variability parameters were identified as clinically most relevant digital biomarker for gait impairment in HD. Altered gait variability represents characteristic irregularity of gait in HD and reflects disease severity.
Biological and clinical changes in premanifest and early stage Huntington's disease in the TRACK-HD study: the 12-month longitudinal analysis
TRACK-HD is a prospective observational study of Huntington's disease (HD) that examines disease progression in premanifest individuals carrying the mutant HTT gene and those with early stage disease. We report 12-month longitudinal changes, building on baseline findings. We did a 12-month follow-up of patients recruited from the four TRACK-HD study sites in Canada, France, the Netherlands, and the UK. Participants were premanifest individuals (preHD) carrying the mutant HTT gene, patients with early HD, and controls matched by age and sex with the combined preHD and early HD groups. Data were collected by use of 3T MRI and clinical, cognitive, quantitative motor, oculomotor, and neuropsychiatric measures. Statistical analysis assessed annualised change with the use of linear regression models to estimate differences between groups. 116 preHD individuals, 114 early HD patients, and 115 people in the control group completed follow-up. Four preHD individuals, nine early HD patients, and eight people in the control group did not complete the follow-up. A further nine participants, who completed follow-up assessments, were unable to undergo MRI. After adjustment for demographics, annualised rates of generalised and regional brain atrophy were higher in preHD and early HD groups than in controls. Whole-brain atrophy rates were 0·20% (95% CI 0·05–0·34; p=0·0071) per year higher in preHD participants and 0·60% (0·44–0·76; p<0·0001) in early HD patients, and caudate atrophy rates were 1·37% (0·99–1·75; p<0·0001) per year higher in preHD and 2·86% (2·34–3·39; p<0·0001) in early HD. Voxel-based morphometry revealed grey-matter and white-matter atrophy, even in subjects furthest from predicted disease onset. Quantitative imaging showed statistically significant associations with disease burden, an indicator of disease pathology, and total functional capacity, a widely-used clinical measure of disease severity. Relative to controls, decline in cognition and quantitative motor function was detectable in both pre- and early HD, as was deterioration in oculomotor function in early HD. Quantitative imaging showed the greatest differentiation across the spectrum of disease and functional measures of decline were sensitive in early HD, with cognitive and quantitative motor impairment also detectable in preHD. We show longitudinal change over 12 months in generalised and regional brain volume, cognition, and quantitative motor tasks in individuals many years from predicted disease onset and show the feasibility of obtaining quantifiable endpoints for future trials. CHDI/HighQ Foundation Inc.
Huntington disease: natural history, biomarkers and prospects for therapeutics
Key Points No disease-modifying treatments are currently available for Huntington disease (HD), but clinical trials of potential compounds are imminent; identification of suitable biomarkers to assess therapeutic efficacy is a research priority Quantifiable measures of patient function, including motor and cognitive assessments, have shown disease-related change in early HD but still lack sensitivity in premanifest cohorts Structural imaging measures such as striatal atrophy show the largest effect sizes both cross-sectionally and longitudinally, and have the potential to track disease progression even in the premanifest period Functional MRI and magnetic resonance spectroscopy are also sensitive for detecting change, but have not yet been well-validated longitudinally PET imaging is quantitative and shows sensitivity to early premanifest disease, and may be useful longitudinally, but has the disadvantage of being expensive and complex Biochemical assays of relevant molecules provide a more direct reflection of disease mechanisms; such measures have not been fully validated, and future work will focus on their development Huntington disease (HD) is considered to be a model neurodegenerative disorder, in that it is caused by a single genetic mutation and is amenable to predictive genetic testing, enabling the entire disease course to be studied. Ross et al . describe the natural history of HD, including the timing of emergence of motor, cognitive and emotional impairments. Building on this information, they review recent progress in the development of biomarkers for HD, and potential future roles of these biomarkers in clinical trials. Huntington disease (HD) can be seen as a model neurodegenerative disorder, in that it is caused by a single genetic mutation and is amenable to predictive genetic testing, with estimation of years to predicted onset, enabling the entire range of disease natural history to be studied. Structural neuroimaging biomarkers show that progressive regional brain atrophy begins many years before the emergence of diagnosable signs and symptoms of HD, and continues steadily during the symptomatic or 'manifest' period. The continued development of functional, neurochemical and other biomarkers raises hopes that these biomarkers might be useful for future trials of disease-modifying therapeutics to delay the onset and slow the progression of HD. Such advances could herald a new era of personalized preventive therapeutics. We describe the natural history of HD, including the timing of emergence of motor, cognitive and emotional impairments, and the techniques that are used to assess these features. Building on this information, we review recent progress in the development of biomarkers for HD, and potential future roles of these biomarkers in clinical trials.
Potential endpoints for clinical trials in premanifest and early Huntington's disease in the TRACK-HD study: analysis of 24 month observational data
TRACK-HD is a prospective observational biomarker study in premanifest and early Huntington's disease (HD). In this report we define a battery of potential outcome measures for therapeutic trials. We assessed longitudinal data collected at baseline, 12 months, and 24 months at sites in Leiden (Netherlands), London (UK), Paris (France), and Vancouver (Canada). Participants were individuals without HD but carrying the mutant HTT gene (ie, premanifest HD), patients with early HD, and healthy control individuals matched by age and sex to the combined HD groups. Data were collected with 3T MRI, clinical, cognitive, quantitative motor, oculomotor, and neuropsychiatric assessments. We estimated adjusted, between-group differences in rates of change in these measures and concomitant longitudinal effect sizes. Longitudinal data were available for 116 control individuals, 117 premanifest gene carriers, and 116 participants with early HD. Significantly greater progressive grey-matter, white-matter, whole-brain, and regional atrophy was recorded in the premanifest and early HD groups than in the control group. Effect sizes for atrophy rates between participants with early HD and controls were largest in the caudate (2·04, 95% CI 1·68 to 2·48) and white matter (1·70, 1·40 to 2·08). Functional, quantitative motor, and cognitive measures deteriorated to a greater extent in the early HD group than in controls, with the largest effect size in the symbol digit modality test (1·00, 0·67 to 1·27). In the early HD group, changes in structural imaging and various cognitive and quantitative motor scores were associated with worsening total motor score (TMS) and total functional capacity (TFC). In the premanifest group, despite significant declines in regional and overall brain volumes, few functional variables showed significant 24 month change compared with controls; TMS, emotion recognition, and speeded tapping were exceptions. Premanifest individuals with progression, predefined as an increase in TMS score of 5 points or more, any TFC decline, or a new diagnostic confidence score of 4, exhibited higher rates of brain atrophy and deterioration on some quantitative motor tasks compared with other premanifest participants. On the basis of longitudinal effect size, we recommend several objective outcome measures for clinical trials in participants with early HD. Hypothetical treatment effects defined by slower longitudinal changes in these measures would be detectable over a realistic timescale with practical sample sizes. The restricted 24 month cognitive or motor decline in the premanifest sample illustrates the greater challenge in trial design for this group. CHDI/HighQ Foundation Inc.
Biological and clinical manifestations of Huntington's disease in the longitudinal TRACK-HD study: cross-sectional analysis of baseline data
Huntington's disease (HD) is an autosomal dominant, fully penetrant, neurodegenerative disease that most commonly affects adults in mid-life. Our aim was to identify sensitive and reliable biomarkers in premanifest carriers of mutated HTT and in individuals with early HD that could provide essential methodology for the assessment of therapeutic interventions. This multicentre study uses an extensive battery of novel assessments, including multi-site 3T MRI, clinical, cognitive, quantitative motor, oculomotor, and neuropsychiatric measures. Blinded analyses were done on the baseline cross-sectional data from 366 individuals: 123 controls, 120 premanifest (pre-HD) individuals, and 123 patients with early HD. The first participant was enrolled in January, 2008, and all assessments were completed by August, 2008. Cross-sectional analyses identified significant changes in whole-brain volume, regional grey and white matter differences, impairment in a range of voluntary neurophysiological motor, and oculomotor tasks, and cognitive and neuropsychiatric dysfunction in premanifest HD gene carriers with normal motor scores through to early clinical stage 2 disease. We show the feasibility of rapid data acquisition and the use of multi-site 3T MRI and neurophysiological motor measures in a large multicentre study. Our results provide evidence for quantifiable biological and clinical alterations in HTT expansion carriers compared with age-matched controls. Many parameters differ from age-matched controls in a graded fashion and show changes of increasing magnitude across our cohort, who range from about 16 years from predicted disease diagnosis to early HD. These findings might help to define novel quantifiable endpoints and methods for rapid and reliable data acquisition, which could aid the design of therapeutic trials. CHDI/High Q Foundation.
Pridopidine for the treatment of motor function in patients with Huntington's disease (MermaiHD): a phase 3, randomised, double-blind, placebo-controlled trial
Huntington's disease is a progressive neurodegenerative disorder, characterised by motor, cognitive, and behavioural deficits. Pridopidine belongs to a new class of compounds known as dopaminergic stabilisers, and results from a small phase 2 study in patients with Huntington's disease suggested that this drug might improve voluntary motor function. We aimed to assess further the effects of pridopidine in patients with Huntington's disease. We undertook a 6 month, randomised, double-blind, placebo-controlled trial to assess the efficacy of pridopidine in the treatment of motor deficits in patients with Huntington's disease. Our primary endpoint was change in the modified motor score (mMS; derived from the unified Huntington's disease rating scale) at 26 weeks. We recruited patients with Huntington's disease from 32 European centres; patients were aged 30 years or older and had an mMS of 10 points or greater at baseline. Patients were randomly assigned (1:1:1) to receive placebo, 45 mg per day pridopidine, or 90 mg per day pridopidine by use of centralised computer-generated codes. Patients and investigators were masked to treatment assignment. We also assessed the safety and tolerability profile of pridopidine. For our primary analysis, all patients were eligible for inclusion in our full analysis set, in which we used the last observation carried forward method for missing values. We used an analysis of covariance model and the Bonferroni method to adjust for multiple comparisons. We used a prespecified per-protocol population as our sensitivity analysis. The α level was 0·025 for our primary analysis and 0·05 overall. This trial is registered with ClinicalTrials.gov, number NCT00665223. At 26 weeks, in our full analysis set the difference in mean mMS was −0·99 points (97·5% CI −2·08 to 0·10, p=0·042) in patients who received 90 mg per day pridopidine (n=145) versus those who received placebo (n=144), and −0·36 points (−1·44 to 0·72, p=0·456) in those who received 45 mg per day pridopidine (n=148) versus those who received placebo. At the 90 mg per day dose, in our per-protocol population (n=114), the reduction in the mMS was of −1·29 points (−2·47 to −0·12; p=0·014) compared with placebo (n=120). We did not identify any changes in non-motor endpoints at either dose. Pridopidine was well tolerated and had an adverse event profile similar to that of placebo. This study did not provide evidence of efficacy as measured by the mMS, but a potential effect of pridopidine on the motor phenotype of Huntington's disease merits further investigation. Pridopidine up to 90 mg per day was well tolerated in patients with Huntington's disease. NeuroSearch A/S.
Cognitive decline in Huntington’s disease in the Digitalized Arithmetic Task (DAT)
Efficient cognitive tasks sensitive to longitudinal deterioration in small cohorts of Huntington's disease (HD) patients are lacking in HD research. We thus developed and assessed the digitized arithmetic task (DAT), which combines inner language and executive functions in approximately 4 minutes. We assessed the psychometric properties of DAT in three languages, across four European sites, in 77 early-stage HD patients (age: 52 ± 11 years; 27 females), and 57 controls (age: 50 ± 10, 31 females). Forty-eight HD patients and 34 controls were followed up to one year with 96 participants who underwent MRI brain imaging (HD patients = 46) at baseline and 50 participants (HD patients = 22) at one year. Linear mixed models and Pearson correlations were used to assess associations with clinical assessment. At baseline, HD patients were less accurate (p = 0.0002) with increased response time (p<0.0001) when compared to DAT in controls. Test-retest reliability in HD patients ranged from good to excellent for response time (range: 0.63-0.79) and from questionable to acceptable for accuracy (range: r = 0.52-0.69). Only DAT, the Mattis Dementia Rating Scale, the Symbol Digit Modalities Test, and Total Functional Capacity scores were able to detect a decline within a one-year follow-up in HD patients (all p< 0.05). In contrast with all the other cognitive tasks, DAT correlated with striatal atrophy over time (p = 0.037) but not with motor impairment. DAT is fast, reliable, motor-free, applicable in several languages, and able to unmask cognitive decline correlated with striatal atrophy in small cohorts of HD patients. This likely makes it a useful endpoint in future trials for HD and other neurodegenerative diseases.
Multifeature quantitative motor assessment of upper limb ataxia including drawing and reaching
Objective Voluntary upper limb movements are an ecologically important yet insufficiently explored digital‐motor outcome domain for trials in degenerative ataxia. We extended and validated the trial‐ready quantitative motor assessment battery “Q‐Motor” for upper limb movements with clinician‐reported, patient‐focused, and performance outcomes of ataxia. Methods Exploratory single‐center cross‐sectional assessment in 94 subjects (46 cross‐genotype ataxia patients; 48 matched controls), comprising five tasks measured by force transducer and/or position field: Finger Tapping, diadochokinesia, grip‐lift, and—as novel implementations—Spiral Drawing, and Target Reaching. Digital‐motor measures were selected if they discriminated from controls (AUC >0.7) and correlated—with at least one strong correlation (rho ≥0.6)—to the Scale for the Assessment and Rating of Ataxia (SARA), activities of daily living (FARS‐ADL), and the Nine‐Hole Peg Test (9HPT). Results Six movement features with 69 measures met selection criteria, including speed and variability in all tasks, stability in grip‐lift, and efficiency in Target Reaching. The novel drawing/reaching tasks best captured impairment in dexterity (|rho9HPT| ≤0.81) and FARS‐ADL upper limb items (|rhoADLul| ≤0.64), particularly by kinematic analysis of smoothness (SPARC). Target hit rate, a composite of speed and endpoint precision, almost perfectly discriminated ataxia and controls (AUC: 0.97). Selected measures in all tasks discriminated between mild, moderate, and severe impairment (SARA upper limb composite: 0–2/>2–4/>4–6) and correlated with severity in the trial‐relevant mild ataxia stage (SARA ≤10, n = 20). Interpretation Q‐Motor assessment captures multiple features of impaired upper limb movements in degenerative ataxia. Validation with key clinical outcome domains provides the basis for evaluation in longitudinal studies and clinical trial settings.
Technology acceptance of digital devices for home use: Qualitative results of a mixed methods study
Objective Digital devices have demonstrated benefits to patients with chronic and neurodegenerative diseases. But when patients use medical devices in their homes, the technologies have to fit into their lives. We investigated the technology acceptance of seven digital devices for home use. Methods We conducted 60 semi-structured interviews with participants of a larger device study on their views on the acceptability of seven devices. Transcriptions were analysed using qualitative content analysis. Results Based on the unified theory of acceptance and use of technology, we evaluated effort, facilitating conditions, performance expectancy and social influence of each device. In the effort category, five themes emerged: (a) the hassle to use the device; (b) its usability; (c) comfort; (d) disturbance to daily life; and (e) problems during usage. Facilitating conditions consisted of five themes: (a) expectations regarding a device; (b) quality of the instructions; (c) insecurities with usage; (d) possibilities of optimization; and (e) possibilities to use the device longer. Regarding performance expectancy, we identified three themes: (a) insecurities with the performance of a device; (b) feedback; and (c) motivation for using a device. In the social influence category, three themes emerged: (a) reactions of peers; (b) concerns with the visibility of a device; and (c) concerns regarding data privacy. Conclusions We identify key factors that determine the acceptability of medical devices for home use from the participants’ perspective. These include low effort of use, minor disruptions to their daily lives and good support from the study team.