The effects of multidisciplinary rehabilitation in patients with early-to-middle-stage Huntington's disease: a pilot study

Huntington study group's neuropsychology working group position on best practice recommendations for the clinical neuropsychological evaluation of patients with Huntington disease

Objective: Neuropsychological evaluation is critical to detection and management of cognitive and neuropsychiatric changes associated with Huntington disease (HD). Accurate assessment of non-motor complications of HD is critical given the prominent impact on functional disability, frequently commensurate with or exceeding that of motor symptoms. The increasing emphasis on developing disease-modifying therapies targeting cognitive decline in HD requires consensus on clinical neuropsychological assessment methods. The Neuropsychology Working Group (NPWG) of the Huntington Study Group (HSG) sought to provide evidence and consensus-based, practical guidelines for the evaluation of cognitive and neuropsychiatric symptoms associated with HD. Method: The NPWG recruited a multi-disciplinary group of neuropsychologists, neurologists, and psychiatrists to inform best practices in assessing, diagnosing, and treating the non-motor symptoms in HD. A review was circulated among the NPWG, and in an iterative process informed by reviewed literature, best practices in neuropsychological evaluation of patients with HD were identified. Results: A brief review of the available literature and rational for a clinical consensus battery is offered. Conclusion: Clinical neuropsychologists are uniquely positioned to both detect and characterize the non-motor symptoms in HD, and further, provide neurologists and allied health professions with clinically meaningful information that impacts functional outcomes and quality of life. The NPWG provides guidance on best practices to clinical neuropsychologists in this statement. A companion paper operationalizing clinical application of previous research-based non-motor diagnostic criteria for HD is forthcoming, which also advises on non-motor symptom screening methods for the non-neuropsychologist working with HD.

Brain-Periphery Interactions in Huntington's Disease: Mediators and Lifestyle Interventions

Prominent pathological features of Huntington's disease (HD) are aggregations of mutated Huntingtin protein (mHtt) in the brain and neurodegeneration, which causes characteristic motor (such as chorea and dystonia) and non-motor symptoms. However, the numerous systemic and peripheral deficits in HD have gained increasing attention recently, since those factors likely modulate disease progression, including brain pathology. While whole-body metabolic abnormalities and organ-specific pathologies in HD have been relatively well described, the potential mediators of compromised inter-organ communication in HD have been insufficiently characterized. Therefore, we applied an exploratory literature search to identify such mediators. Unsurprisingly, dysregulation of inflammatory factors, circulating mHtt, and many other messenger molecules (hormones, lipids, RNAs) were found that suggest impaired inter-organ communication, including of the gut-brain and muscle-brain axis. Based on these findings, we aimed to assess the risks and potentials of lifestyle interventions that are thought to improve communication across these axes: dietary strategies and exercise. We conclude that appropriate lifestyle interventions have great potential to reduce symptoms and potentially modify disease progression (possibly via improving inter-organ signaling) in HD. However, impaired systemic metabolism and peripheral symptoms warrant particular care in the design of dietary and exercise programs for people with HD.

Treatment of Depression in Huntington's Disease: A Systematic Review

Depression is a common psychiatric disorder among individuals with Huntington's disease (HD). Depression in HD and major depressive disorder appear to have different pathophysiological mechanisms. Despite the unique pathophysiology, the treatment of depression in HD is based on data from the treatment of major depressive disorder in the general population. The objective of this systematic review was to conduct a comprehensive evaluation of the available evidence. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Studies on the treatment of depression in HD were identified by searching MEDLINE, Embase, and PsycInfo. The initial search yielded 2,771 records, 41 of which were ultimately included. There were 19 case reports, seven case series, three cross-sectional studies, one qualitative study, nine nonrandomized studies, and two randomized trials among the included studies. The most common assessment tools were the Hospital Anxiety and Depression Scale (N=8), the Beck Depression Inventory (N=6), and the Hamilton Depression Rating Scale (N=6). Only 59% of the included studies assessed depressive symptoms with a scoring system. The pharmacological options for the treatment of depression included antidepressants and antipsychotics. Nonpharmacological approaches were multidisciplinary rehabilitation, psychotherapy, and neurostimulation. Limited evidence on the treatment of depression in HD was available, and this literature consisted mainly of case reports and case series. This systematic review highlights the knowledge gap and the pressing need for HD-specific research to determine the efficacy of treatment approaches for depression in HD.

Update of Rehabilitation in Huntington's Disease: Narrative Review

Huntington's disease (HD) is a neurodegenerative disease that has motor dysfunction, predominantly chorea, cognitive impairment, and psychiatric disturbances as symptoms. Treatment is directed to reduce the severity of symptoms, although there are few studies and no clinical guidelines for rehabilitation in HD. Therefore, this review aimed to establish an effective rehabilitation approach for HD according to the stage of the disease. In the early stage of HD, the motor symptoms are mild, and psychological symptoms occur. Treatment in this period should focus on aerobic and resistance exercises, task-specific training, secondary prevention education, cognitive training, and psychological management. In the middle stage of HD, the motor symptoms are more severe. Task-specific rehabilitation approaches, education for the patient and caregiver, functional respiratory exercises, activities of daily living training, multidisciplinary and multimodal daycare rehabilitation are helpful to patients in this stage. At the late stage of HD, most patients need complete support for activity of daily living. Mobility and balance evaluation and prevention strategies should be focused on for safety, and respiratory exercises and physical exercise to prevent complications in patients with severely impaired mobility should be considered based on the patient's condition. Programmed rehabilitation management based on the stage of the disease is effective for patients with HD.

Physical activity and lifestyle modifications in the treatment of neurodegenerative diseases

Neurodegenerative diseases have reached alarming numbers in the past decade. Unfortunately, clinical trials testing potential therapeutics have proven futile. In the absence of disease-modifying therapies, physical activity has emerged as the single most accessible lifestyle modification with the potential to fight off cognitive decline and neurodegeneration. In this review, we discuss findings from epidemiological, clinical, and molecular studies investigating the potential of lifestyle modifications in promoting brain health. We propose an evidence-based multidomain approach that includes physical activity, diet, cognitive training, and sleep hygiene to treat and prevent neurodegenerative diseases.

Cognition-oriented treatments and physical exercise on cognitive function in Huntington's disease: a systematic review

Cognitive impairment is prevalent in Huntington's disease (HD), with no treatments currently available. While cognition-oriented treatments and physical exercise have shown efficacy in improving cognition in other populations, they have not been systematically reviewed in HD. This systematic review aims to examine the effects of cognitive and exercise interventions on cognition in HD, along with effects on psychosocial function, functional independence, and neuroimaging outcomes. Seventeen studies (three cognitive, seven exercise, seven combining cognitive and physical exercise) were included. While there was generally low certainty of evidence, interventions that included cognitive training appeared to have larger effect sizes on cognition, while physical exercise (alone or combined with cognitive rehabilitation or stimulation) showed negligible effect sizes. On the other hand, combined interventions had larger effects on psychosocial function. Finally, effects on functional independence appeared negligible following exercise and combined interventions, and effects on neuroimaging outcomes were inconclusive. Larger studies should seek to confirm the benefits of cognitive and physical interventions, and further explore changes in functional independence and neural outcomes.

Clinical Decision Trees to Guide Physical Therapy Management of Persons with Huntington's Disease

BACKGROUND

In 2020, our group published physical therapy clinical practice guidelines (CPG) for people with Huntington's disease (HD). The guideline recommendations were categorized according to six primary movement impairment classifications.

OBJECTIVE

To facilitate implementation of this CPG, we have developed guideline-based algorithms for physical therapy assessments and interventions and recommendations for therapists to overcome barriers to CPG implementation for people with HD.

METHODS

We conducted a literature review of papers that evaluated physical therapy interventions in individuals with HD (n = 26) to identify assessments for each of the primary movement impairment classifications, and then searched for papers (n = 28) that reported their clinometric/psychometric properties in HD. Assessments were evaluated using modified Movement Disorder Society Committee on Rating Scales criteria and other relevant criteria.

RESULTS

We identified a "core set" of physical therapy assessments for persons with HD, including the Six Minute Walk Test, Timed Up and Go Test, Berg Balance Scale, and the Medical Outcomes Study Short Form 36 (SF-36). We then developed guideline-based decision trees to assist in decision making and implementation of the CPG into practice for persons with HD across the continuum of care. Finally, we developed strategies for overcoming barriers to implementation, such as seeking specialized training in HD, engaging caretakers or family members to help the person with HD to exercise, and establishing clinical pathways that support early physical therapy referrals.

CONCLUSION

Knowledge translation documents such as this are essential to promoting implementation of the physical therapy CPGs into clinical practice.

Healthcare professionals' involvement in breaking bad news to newly diagnosed patients with motor neurodegenerative conditions: a qualitative study

PURPOSE

Research on breaking bad news (BBN) in healthcare has mostly focused on the doctor-patient interaction during a single consultation. However, it has been increasingly recognised that BBN is a wider process that also involves other healthcare professionals. This qualitative study explored non-medical¹ healthcare professionals' involvement in BBN to newly diagnosed patients with motor neurodegenerative conditions in the UK.

MATERIALS AND METHODS

19 healthcare professionals working with people with motor neurone disease, multiple sclerosis, Parkinson's disease or Huntington's disease took part in individual, semi-structured interviews which were analysed using thematic analysis.

RESULTS

Four themes were constructed: dealing with the diagnostic aftermath, unpacking the diagnosis, breaking bad news as a balancing act and empowering patients to regain control over their health and lives. Participants reported being broadly involved in BBN by supporting patients with negative diagnostic experiences, re-iterating diagnostic information and helping patients understand the impact of their condition. The challenges of effectively breaking bad news and how these difficult conversations could help empower patients were also emphasised.

CONCLUSIONS

BBN was a critical and challenging aspect of healthcare professionals' clinical work with newly diagnosed patients with motor neurodegenerative conditions. Besides providing information, BBN was perceived as a way to educate patients, encourage them to make decisions and prepare for the future.Implications for rehabilitationBreaking bad news is a potentially under-recognised but significant aspect in the neurorehabilitation of neurodegenerative conditions.Listening to patients' stories about a long and occasionally unsatisfactory diagnostic journey and allowing them to express their frustration can be critical in regaining patients' trust and building a relationship with them.Newly diagnosed patients have not always received adequate information about their condition at diagnosis or they might have not understood or retained that information. It is, therefore, essential that patients' understanding of their condition is assessed, misconceptions are cleared and appropriate information about the nature and impact of the diagnosis is provided.Irrespective of the length of experience, breaking bad news was perceived as a multi-faceted, challenging, stressful and emotionally demanding task.Formal support and specialised training on breaking the bad news that addresses the incurable, unpredictable and progressive nature of motor neurodegenerative conditions could help professionals with this challenging task.

Home-Based Exercise to Improve Motor Functions, Cognitive Functions, and Quality of Life in People with Huntington's Disease: A Systematic Review and Meta-Analysis

Exercise in different settings has become a fundamental part of Huntington's disease (HD) management. The aim of this systematic review and meta-analysis was to investigate the effectiveness of home-based exercises (HBE) in HD. Randomized controlled trials (RCTs) investigating the effect of HBE on motor, cognitive, or health-related quality of life (QoL) outcomes in HD were included. Standardized mean difference (SMD), the 95% confidence interval, and p-values were calculated by comparing the outcomes change between HBE and control groups. Seven RCTs met the inclusion criteria. The included RCTs prescribed different types of HBEs, i.e., aerobic strengthening, walking, balance, and fine motor exercises. The HBE protocol length was between 6 and 36 weeks. The meta-analyses showed a significant effect of HBE intervention on motor function measure by Unified Huntington Disease Rating and overall QoL measure by Short Form-36 post-treatment respectively, [SMD = 0.481, p = 0.048], [SMD = 0.378, p = 0.003]. The pooled analysis did not detect significant changes in cognition, gait characteristics, or functional balance scales. The current study shows the positive effect of HBE in HD, especially on motor function and QoL. No significant adverse events were reported. The current results support the clinical effect of HBE intervention on motor function and QoL in HD patients. However, these results should be taken with caution due to the limited available evidence. Well-designed clinical studies that consider the disease severity and stages are required in the future.

Physical activity and exercise outcomes in Huntington's disease (PACE-HD): results of a 12-month trial-within-cohort feasibility study of a physical activity intervention in people with Huntington's disease

INTRODUCTION

While physical activity (PA) is recognized as important in Huntington's disease (HD) disease management, there has been no long-term evaluation undertaken. We aimed to evaluate the feasibility of a nested (within cohort) randomized controlled trial (RCT) of a physical therapist-led PA intervention.

METHODS

Participants were recruited from six HD specialist centers participating in the Enroll-HD cohort study in Germany, Spain and U.S. Assessments were completed at baseline and 12 months and linked to Enroll-HD cohort data. Participants at three sites (cohort) received no contact between baseline and 12 month assessments. Participants at three additional sites (RCT) were randomized to PA intervention or control group. The intervention consisted of 18 sessions delivered over 12 months; control group participants received no intervention, however both groups completed monthly exercise/falls diaries and 6-month assessments.

RESULTS

274 participants were screened, 204 met inclusion criteria and 116 were enrolled (59 in cohort; 57 in RCT). Retention rates at 12-months were 84.7% (cohort) and 79.0% (RCT). Data completeness at baseline ranged from 42.3 to 100% and at 12-months 19.2-85.2%. In the RCT, there was 80.5% adherence, high intervention fidelity, and similar adverse events between groups. There were differences in fitness, walking endurance and self-reported PA at 12 months favoring the intervention group, with data completeness >60%. Participants in the cohort had motor and functional decline at rates comparable to previous studies.

CONCLUSION

Predefined progression criteria indicating feasibility were met. PACE-HD lays the groundwork for a future, fully-powered within cohort trial, but approaches to ensure data completeness must be considered.

CLINICALTRIALS

GOV: NCT03344601.

Effects of Exercise on Skeletal Muscle Pathophysiology in Huntington's Disease

Huntington's disease (HD) is a rare, hereditary, and progressive neurodegenerative disease, characterized by involuntary choreatic movements with cognitive and behavioral disturbances. In order to mitigate impairments in motor function, physical exercise was integrated in HD rehabilitative interventions, showing to be a powerful tool to ameliorate the quality of life of HD-affected patients. This review aims to describe the effects of physical exercise on HD-related skeletal muscle disorders in both murine and human models. We performed a literature search using PubMed, Scopus, and Web of Science databases on the role of physical activity in mouse models of HD and human patients. Fifteen publications fulfilled the criteria and were included in the review. Studies performed on mouse models showed a controversial role played by exercise, whereas in HD-affected patients, physical activity appeared to have positive effects on gait, motor function, UHDMRS scale, cognitive function, quality of life, postural stability, total body mass, fatty acid oxidative capacity, and VO2 max. Physical activity seems to be feasible, safe, and effective for HD patients. However, further studies with longer follow-up and larger cohorts of patients will be needed to draw firm conclusions on the positive effects of exercise for HD patients.

Profiling Social Cognition in Premanifest Huntington's Disease

OBJECTIVE

Discrepancies exist in reports of social cognition deficits in individuals with premanifest Huntington's disease (HD); however, the reason for this variability has not been investigated. The aims of this study were to (1) evaluate group- and individual-level social cognitive performance and (2) examine intra-individual variability (dispersion) across social cognitive domains in individuals with premanifest HD.

METHOD

Theory of mind (ToM), social perception, empathy, and social connectedness were evaluated in 35 individuals with premanifest HD and 29 healthy controls. Cut-off values beneath the median and 1.5 × the interquartile range below the 25th percentile (P25 - 1.5 × IQR) of healthy controls for each variable were established for a profiling method. Dispersion between social cognitive domains was also calculated.

RESULTS

Compared to healthy controls, individuals with premanifest HD performed worse on all social cognitive domains except empathy. Application of the profiling method revealed a large proportion of people with premanifest HD fell below healthy control median values across ToM (>80%), social perception (>57%), empathy (>54%), and social behaviour (>40%), with a percentage of these individuals displaying more pronounced impairments in empathy (20%) and ToM (22%). Social cognition dispersion did not differ between groups. No significant correlations were found between social cognitive domains and mood, sleep, and neurocognitive outcomes.

CONCLUSIONS

Significant group-level social cognition deficits were observed in the premanifest HD cohort. However, our profiling method showed that only a small percentage of these individuals experienced marked difficulties in social cognition, indicating the importance of individual-level assessments, particularly regarding future personalised treatments.

Measures of postural control and mobility during dual-tasking as candidate markers of instability in Huntington's disease

BACKGROUND

Individuals with Huntington's disease (HD) have impairments in performing dual-tasks, however, there is limited information about the effects of changing postural and cognitive demands as well as which measures are best suited as markers of underlying motor-cognitive interference.

METHODS

Forty-three individuals with HD and 15 healthy controls (HC) completed single tasks of walking (Timed Up & Go (TUG), 7 m walk), standing (feet together, feet apart and foam surface) and seated cognitive performance (Stroop, Symbol Digit Modalities Test (SDMT), Delis-Kaplan Executive Function System (DKEFS) Sorting test) and dual cognitive-motor tasks while standing (+ Stroop) and walking (+ DKEFS, TUG cognitive). APDM Opal sensors recorded measures of postural sway and time to complete motor tasks.

RESULTS

Individuals with HD had a greater increase in standing postural sway compared to HC from single to dual-tasks and with changes to support surface. Both groups demonstrated a decrease in gait performance during the TUG cognitive, however, this difference was greater in people with HD compared to HC. While those with HD showed a greater dual-task motor cost compared to HC, both groups behaved similarly as condition complexity increased.

CONCLUSIONS

Standing postural sway is a more sensitive marker of instability than change in standard gait speed, particularly under dual-task conditions. The more complex TUG cognitive is a sensitive measure of walking dual-task performance. The results of this study provide insights about the nature of motor-cognitive impairments in HD and provide support for a distinction between static and dynamic postural control mechanisms during performance of dual-tasks.

Huntington's disease: diagnosis and management

Huntington's disease (HD) is an inherited neurodegenerative disease characterised by neuropsychiatric symptoms, a movement disorder (most commonly choreiform) and progressive cognitive impairment. The diagnosis is usually confirmed through identification of an increased CAG repeat length in the huntingtin gene in a patient with clinical features of the condition. Though diagnosis is usually straightforward, unusual presentations can occur, and it can be difficult to know when someone has transitioned from being an asymptomatic carrier into the disease state. This has become increasingly important recently, with several putative disease-modifying therapies entering trials. A growing number of conditions can mimic HD, including rare genetic causes, which must be considered in the event of a negative HD genetic test. Patients are best managed in specialist multidisciplinary clinics, including when considering genetic testing. Current treatments are symptomatic, and largely directed at the chorea and neurobehavioural problems, although supporting trial evidence for these is often limited.

Approach to Posture and Gait in Huntington's Disease

Disturbances of gait occur in all stages of Huntington’s disease (HD) including the premanifest and prodromal stages. Individuals with HD demonstrate the slower speed of gait, shorter stride length, and increased variability of gait parameters as compared to controls; cognitive disturbances in HD often compound these differences. Abnormalities of gait and recurrent falls lead to decreased quality of life for individuals with HD throughout the disease. This scoping review aims to outline the cross-disciplinary approach to gait evaluation in HD and will highlight the utility of objective measures in defining gait abnormalities in this patient population.

Healthcare Delivery and Huntington's Disease During the Time of COVID-19

BACKGROUND

Safer-at-home orders during the COVID-19 pandemic altered the structure of clinical care for Huntington's disease (HD) patients. This shift provided an opportunity to identify limitations in the current healthcare infrastructure and how these may impact the health and well-being of persons with HD.

OBJECTIVE

The study objectives were to assess the feasibility of remote healthcare delivery in HD patients, to identify socioeconomic factors which may explain differences in feasibility and to evaluate the impact of safer-at-home orders on HD patient stress levels.

METHODS

This observational study of a clinical HD population during the 'safer-at-home' orders asked patients or caregivers about their current access to healthcare resources and patient stress levels. A chart review allowed for an assessment of socioeconomic status and characterization of HD severity.

RESULTS

Two-hundred and twelve HD patients were contacted with 156 completing the survey. During safer-at-home orders, the majority of HD patients were able to obtain medications and see a physician; however, 25% of patients would not commit to regular telehealth visits, and less than 50% utilized an online healthcare platform. We found that 37% of participants were divorced/single, 39% had less than a high school diploma, and nearly 20% were uninsured or on low-income health insurance. Patient stress levels correlated with disease burden.

CONCLUSION

A significant portion of HD participants were not willing to participate in telehealth services. Potential explanations for these limitations may include socioeconomic barriers and caregiving structure. These observations illustrate areas for clinical care improvement to address healthcare disparities in the HD community.

Physical exercise improves quality of life, depressive symptoms, and cognition across chronic brain disorders: a transdiagnostic systematic review and meta-analysis of randomized controlled trials

We performed a meta-analysis to synthesize evidence on the efficacy and safety of physical exercise as an add-on therapeutic intervention for quality of life (QoL), depressive symptoms and cognition across six chronic brain disorders: Alzheimer's disease, Huntington's disease, multiple sclerosis, Parkinson's disease, schizophrenia and unipolar depression. 122 studies ( = k) (n = 7231) were included. Exercise was superior to treatment as usual in improving QoL (k = 64, n = 4334, ES = 0.40, p < 0.0001), depressive symptoms (k = 60, n = 2909, ES = 0.78, p < 0.0001), the cognitive domains attention and working memory (k = 21, n = 1313, ES = 0.24, p < 0.009), executive functioning (k = 14, n = 977, ES = 0.15, p = 0.013), memory (k = 12, n = 994, ES = 0.12, p = 0.038) and psychomotor speed (k = 16, n = 896, ES = 0.23, p = 0.003). Meta-regression showed a dose-response effect for exercise time (min/week) on depressive symptoms (β = 0.007, p = 0.012). 69% of the studies that reported on safety, found no complications. Exercise is an efficacious and safe add-on therapeutic intervention showing a medium-sized effect on QoL and a large effect on mood in patients with chronic brain disorders, with a positive dose-response correlation. Exercise also improved several cognitive domains with small but significant effects.

The effects of multidisciplinary rehabilitation on neuroimaging, biological, cognitive and motor outcomes in individuals with premanifest Huntington's disease

BACKGROUND

Huntington's disease (HD) is a chronic, progressive neurodegenerative condition for which there are currently no proven disease-modifying therapies. Lifestyle factors have been shown to impact on the age of disease onset and progression of disease features. We therefore investigated the effects of a nine-month multidisciplinary rehabilitation intervention on neuroimaging, biological and clinical disease outcomes in individuals with premanifest HD.

METHODS

31 individuals with premanifest HD participated in the study. Eighteen participants underwent a nine-month multidisciplinary rehabilitation intervention comprising aerobic and resistance exercise, computerised cognitive training, dual-task training and sleep hygiene and nutritional guidance. The remaining 13 participants were allocated to a standard care control group. Neuroimaging, biological, cognitive, motor and cardiorespiratory fitness data was collected.

RESULTS

Participants displayed good adherence (87%) and compliance (85%) to the intervention. Maintenance of the shape of the right putamen was observed in the intervention group when compared to the control group. The intervention group displayed significant improvements in verbal learning and memory, attention, cognitive flexibility and processing speed following the intervention when compared to the control group. Performance on the mini-social cognition and emotional assessment (mini-SEA) was maintained in the intervention group, but decreased in the control group. No changes were observed in serum neurofilament light protein levels, postural stability outcomes or cardiorespiratory fitness.

CONCLUSION

This study adds to the accumulating body of literature to suggest that multidisciplinary rehabilitation is of clinical benefit for individuals with HD. Large randomised controlled trials are necessary to determine the extent to which benefits occur across the spectrum of the disease.

The relationship between lifestyle and serum neurofilament light protein in Huntington's disease

OBJECTIVES

Serum neurofilament light protein (NfL) is a promising marker of disease onset and progression in Huntington's disease (HD). This study investigated associations between lifestyle factors and NfL levels in HD mutation carriers compared to healthy age- and sex-matched controls.

MATERIALS AND METHODS

Participants included 29 HD mutation carriers and 15 healthy controls. Associations between serum NfL concentrations and lifestyle factors, including cardiorespiratory fitness, social network size and diversity, physical activity, cognitive reserve, smoking status, and alcohol consumption, were examined using a stepwise multivariable linear regression model.

RESULTS

Higher NfL levels were associated with lower cognitive reserve, social network size and diversity and cardiorespiratory fitness in HD mutation carriers. Group × lifestyle factor effects were observed between lower serum NfL levels and a greater social network diversity.

CONCLUSION

These findings highlight a relationship between lifestyle factors and NfL levels in HD mutations carriers; however, longitudinal studies are required to confirm if these observed relationships persist over time.

Huntington's Disease Clinical Trials Corner: January 2019

In this edition of the Huntington's Disease Clinical Trials Corner we expand on the GENERATION-HD1 and PACE-HD trials, and we list all currently registered and ongoing clinical trials in Huntington's disease.

Clinical recommendations to guide physical therapy practice for Huntington disease

OBJECTIVE

In the past decade, an increasing number of studies have examined the efficacy of physical therapy interventions in people with Huntington disease (HD).

METHODS

We performed a mixed-methods systematic review using Joanna Briggs Institute (JBI) methodology and included experimental and observational study designs. The search resulted in 23 quantitative studies and 3 qualitative studies from which we extracted data using JBI standardized extraction tools. Results of this review suggested that physical therapy interventions may improve motor impairments and activity limitations in people with HD. Here, we expand on the review findings to provide specific recommendations to guide clinical practice.

RESULTS

We recommend the following specific physical therapy interventions for people with HD: aerobic exercise (grade A evidence), alone or in combination with resistance training to improve fitness and motor function, and supervised gait training (grade A evidence) to improve spatiotemporal features of gait. In addition, there is weak (grade B) evidence that exercise training improves balance but does not show a reduction in the frequency of falls; inspiratory and expiratory training improves breathing function and capacity; and training of transfers, getting up from the floor, and providing strategies to caregivers for involvement in physical activity in the midstages of HD may improve performance. There is expert consensus for the use of positioning devices, seating adaptations, and caregiver training in late stages of HD.

CONCLUSIONS

There is strong evidence to support physical therapy interventions to improve fitness, motor function, and gait in persons with HD.

Multidisciplinary rehabilitation reduces hypothalamic grey matter volume loss in individuals with preclinical Huntington's disease: A nine-month pilot study

BACKGROUND

Hypothalamic pathology is a well-documented feature of Huntington's disease (HD) and is believed to contribute to circadian rhythm and habitual sleep disturbances. Currently, no therapies exist to combat hypothalamic changes, nor circadian rhythm and habitual sleep disturbances in HD.

OBJECTIVE

To evaluate the effects of multidisciplinary rehabilitation on hypothalamic volume, brain-derived neurotrophic factor (BDNF), circadian rhythm and habitual sleep in individuals with preclinical HD.

METHODS

Eighteen individuals with HD (ten premanifest and eight prodromal) undertook a nine-month multidisciplinary rehabilitation intervention (intervention group), which included exercise, cognitive and dual task training and social events, and were compared to a community sample of eleven individuals with premanifest HD receiving no intervention (control group). Hypothalamic volume, serum BDNF, salivary cortisol and melatonin concentrations, subjective sleep quality, daytime somnolence, habitual sleep-wake patterns, stress and anxiety and depression symptomatology were evaluated.

RESULTS

Hypothalamus grey matter volume loss was significantly attenuated in the intervention group compared to the control group after controlling for age, gender, Unified Huntington's Disease Rating Scale-Total Motor Score and number of cytosine-adenine-guanine repeats. Serum BDNF levels were maintained in the intervention group, but decreased in the control group following the study period. Both groups exhibited decreases in cortisol and melatonin concentrations. No changes were observed in sleep or mood outcomes.

CONCLUSIONS

This exploratory study provides evidence that multidisciplinary rehabilitation can reduce hypothalamic volume loss and maintain peripheral BDNF levels in individuals with preclinical HD but may not impact on circadian rhythm. Larger, randomised controlled trials are required to confirm these findings.

Exercise Interventions in Huntington's Disease: An Individual Patient Data Meta-Analysis

Background

Physical activity may be beneficial in Huntington's disease (HD); however, studies to date have been underpowered to detect change. We combined data from five randomized controlled feasibility trials using individual patient data meta-analyses.

Methods/Design

All trial interventions comprised a combination of supervised and self-directed physical activity, with varied emphasis on aerobic, strength, endurance, flexibility, and task training. Duration ranged from 8 to 16 weeks. The primary outcome was the modified Unified Huntington's Disease Rating Motor Score. Secondary outcomes included the Symbol Digit Modality Test, Berg Balance Scale, 30-second Chair stand, Timed Up and Go, Gait Speed, Physical Performance Test, Six-Minute Walk, International Physical Activity Questionnaire, Hospital Anxiety and Depression Scale, EuroQol Health Utility Index, and Short-Form 36 Health Related Quality of Life Scale. The primary analysis utilized a two-stage approach. A one-stage approach was explored as a sensitivity analysis using a cross-classified (by study site) linear mixed-effects model.

Results

One hundred twenty-one participants provided complete data. Risk of bias was moderate; however, primary outcomes were blind assessed. Primary pooled effect estimates adjusted for baseline modified motor score (95% confidence interval) were 0.2 (-2.1 to 2.6) favoring control. There was considerable heterogeneity between the studies.

Conclusions

There was no evidence of an exercise effect on the modified motor score in these relatively short-duration interventions. Longer-duration trials incorporating supervised components meeting frequency, intensity, time, and type principles are required. Lack of common outcomes limited the analysis and highlight the importance of a core outcome set for evaluating exercise in HD.

Ancillary Service Utilization and Impact in Huntington's Disease

BACKGROUND

Prior Huntington's disease (HD) studies suggest ancillary services improve motor symptoms, cognition, mood, and quality of life but frequency of use and clinicalcharacteristics are unclear.

OBJECTIVE

Describe ancillary service utilization in a cohort of individuals with HD and determine which participant characteristics are associated with ancillary service utilization.

METHODS

Retrospective cross-sectional analysis of Enroll-HD database. Participants were grouped by therapy: physical and/or occupational (PT/OT), psychotherapy and/or counseling (PC), speech and/or swallowing (ST). We performed bivariate comparisons analysis of demographic and disease characteristics between those with/without each therapy and to analyze one-year mean change in assessment scores.

RESULTS

Of 4751 participants, 1537 (32.35%) utilized therapies (11.82% PT/OT, 5.33% PC, 3.01% ST, 1.98% all three, 10.21% two therapies). PT/OT participants had worse motor and functional scores: mean UHDRS motor score (41.17 vs. 38.05, p = 0.002), median total functional capacity score (TFC) (8.00 vs. 9.00, p < 0.001). PC participants had worse mood but better cognitive and functional scores: median depression score (7.00 vs. 2.00, p < 0.001), median MMSE (28.00 vs. 26.00, p < 0.001), median TFC (10.00 vs. 8.00, p < 0.001). ST participants had more dysarthria, and worse cognitive and functional scores: dysarthria (32.2% vs. 20.1% p < 0.001), mean correct Symbol Digit Modality Test (16.79 vs. 23.27, p < 0.001), median TFC (6.00 vs. 9.00, p < 0.001). Over one year, PC participants' depression scores improved compared to untreated (- 1.24 vs. - 0.11, p = 0.040). ST participants' depression scores worsened (1.14 vs. - 0.23, p = 0.044). Mean change in TFC was not significant for any therapies.

CONCLUSIONS

Only 32% of Enroll-HD site participants received ancillary services. Use correlated with expected clinical characteristics, though impact of use remains unclear.

Exercise in Huntington's Disease: Current State and Clinical Significance

Background

Huntington's disease (HD) is a rare, progressive neurodegenerative disease. Currently, there is no cure for the disease, but treatment may alleviate HD symptoms. In recent years, several exercise training interventions have been conducted in HD patients. In the current article, we review previous studies investigating targeted exercise training interventions in HD patients.

Methods

We performed a literature search using the PubMed, Scopus, Web of Science, and Google Scholar databases on exercise training interventions in HD patients. Six publications fulfilled the criteria and were included in the review.

Results

Exercise training resulted in beneficial effects on cardiovascular and mitochondrial function. Training effects on cognition, motor function, and body composition were less congruent, but a positive effect seems likely. Health-related quality of life during the training interventions was stable. Most studies reported no related adverse events in response to training.

Discussion

Exercise training seems to be safe and feasible in HD patients. However, current knowledge is mainly based on short, small-scale studies and it cannot be transferred to all HD patients. Therefore, longer-term interventions with larger HD patient cohorts are necessary to draw firm conclusions about the potentially positive effects of exercise training in HD patients.

Effects of multidisciplinary therapy on physical function in Huntington's disease

OBJECTIVE

The primary objective of this trial was to evaluate the effects of outpatient multidisciplinary therapy, compared to usual care, on measures of physical function and muscle strength in patients with manifest Huntington's disease (HD).

METHODS

Twenty-two patients with clinically verified HD were randomized to receive 36 weeks of outpatient multidisciplinary therapy or usual care. Outpatient multidisciplinary therapy comprised 9 months of supervised exercise, cognitive therapy and self-directed home-based exercise. Usual care consisted of standard medical care. Patients were assessed at 0 and 36 weeks by blinded assessors. The primary outcome was changed in mobility as measured by the 10-m Timed Walk Test. Secondary outcome measures included changes in manual dexterity (Timed Nut and Bolt Test), balance (Berg Balance Scale), cardiorespiratory endurance (6-Minute Walk Test) and upper and lower extremity muscle strength (isokinetic and isometric muscle strength and 10 Repetition Sit-to-Stand Tests).

RESULTS

Patients receiving outpatient multidisciplinary therapy demonstrated significantly enhanced manual dexterity (P < 0.05) and lower extremity muscle strength (P < 0.05) than patients receiving usual care. No significant differences in mobility, balance, cardiorespiratory endurance and upper extremity strength outcomes were observed between groups after the intervention period. There were no adverse events associated with multidisciplinary therapy.

CONCLUSION

Our findings suggest that outpatient multidisciplinary therapy has positive effects on manual dexterity and muscle strength, but no meaningful effects on mobility, balance, cardiorespiratory endurance and upper extremity muscle strength in patients with HD. Larger randomized controlled trials are needed to confirm these preliminary findings.

Cognitive Performance After a One-Year Multidisciplinary Intensive Rehabilitation Program for Huntington's Disease: An Observational Study

BACKGROUND

Studies of physical therapy and multidisciplinary rehabilitation programs for Huntington's disease (HD) have shown improvements in gait function, balance, and physical quality of life. There is a gap in the literature on effects of cognitive interventions and the potential to improve cognitive performance.

OBJECTIVE

To assess changes in cognitive performance among patients with early to middle stage HD as secondary analyses from a one-year multidisciplinary rehabilitation program. The program included cognitive stimulation as a non-specific cognitive intervention in addition to physical interventions.

METHODS

A one-year rehabilitation program that included comprehensive neuropsychological assessments was completed by 31 out 37 participants with early to middle stages of HD. Socio-demographic and clinical information was recorded. A battery of neuropsychological tests was used to measure cognitive functions before and after the intervention. Descriptive statistics was used for sample characteristics. Paired sample t-tests and nonparametric Wilcoxon Signed ranked tests were used to compare cognitive measures at both time points.

RESULTS

Scores on the Symbol Digit Modalities Test (SDMT) were significantly lower post intervention. There were no significant differences in all other measures. Scores on the Stroop color naming and California Verbal Learning Test-II (CVLT-II) long-term delayed recall tasks showed tendencies towards lower scores post intervention.

CONCLUSIONS

An intensive multidisciplinary rehabilitation program for patients with HD was generally well tolerated and feasible, with no indication of negative effects on cognition. Neuropsychological measures overall remained stable following an intensive multidisciplinary rehabilitation program, however continued progression of cognitive impairment was evident on the SDMT, suggesting that disease progression is not halted. Randomized controlled trials are needed to verify these findings.

Huntington's disease: Managing neuropsychiatric symptoms in Huntington's disease

OBJECTIVES

This clinical update review focuses on the management of the neuropsychiatric manifestations of Huntington's disease (HD). The review highlights current issues regarding pharmacological and non-pharmacological treatment, putative therapeutics and recent relevant research findings in this area.

CONCLUSIONS

Neuropsychiatric symptoms may precede the classic motor clinical symptoms of HD (prodromal HD) by decades and cause significant functional impairment. Early recognition and comprehensive non-pharmacological, usually in combination with pharmacological, treatment is essential.

Understandings of psychological difficulties in people with the Huntington's disease gene and their expectations of psychological therapy

OBJECTIVES

This study sought to investigate how people who had tested positive for the Huntington's disease (HD) gene mutation understood and experienced psychological distress and their expectations of psychological therapy.

DESIGN

A qualitative methodology was adopted involving semi-structured interviews and interpretative phenomenological analysis (IPA).

METHOD

A total of nine participants (five women and four men) who had opted to engage in psychological therapy were recruited and interviewed prior to the start of this particular psychological therapeutic intervention. Interviews were transcribed verbatim and analysed using IPA whereby themes were analysed within and across transcripts and classified into superordinate themes.

RESULTS

Three superordinate themes were developed: Attributing psychological distress to HD: 'you're blaming everything on that now'; Changes in attributions of distress over time: 'in the past you'd just get on with it'; and Approaching therapy with an open mind, commitment, and hope: 'a light at the end of the tunnel'.

CONCLUSION

Understandings of psychological distress in HD included biological and psychological explanations, with both often being accepted simultaneously by the same individual but with biomedical accounts generally dominating. Individual experience seemed to reflect a dynamic process whereby people's understanding and experience of their distress changed over time. Psychological therapy was accepted as a positive alternative to medication, providing people with HD with hope that their psychological well-being could be enhanced.

PRACTITIONER POINTS

People with the Huntington's disease gene mutation have largely biomedical understandings of their psychological distress. This largely biomedical understanding does not, however, preclude them for being interested in the potential gains resulting from psychological therapy. The mechanisms of psychological therapy should be explained in detail before therapy and explored along with current attributions of distress.

Physical Therapy and Exercise Interventions in Huntington's Disease: A Mixed Methods Systematic Review

Background:

A number of studies evaluating physical therapy and exercise interventions in Huntington’s disease have been conducted over the past 15 years. However, an assessment of the quality and strength of the evidence in support of these interventions is lacking.

Objective:

The purpose of this systematic review was to investigate the effectiveness of physical therapy and exercise interventions in people with Huntington’s disease, and to examine the perceptions of patients, families and caregivers of these interventions.

Methods:

This mixed-methods systematic review utilized the Joanna Briggs Institute (JBI) approach and extraction tools to evaluate the literature from January 2003 until May 2016. The review considered interventions that included exercise and physical therapy interventions, and included both quantitative and qualitative outcome measures.

Results:

Twenty (20) studies met the inclusion criteria, including eighteen (18) that had quantitative outcome measures and two (2) that utilized qualitative methods. JBI Levels of evidence for the 18 quantitative studies were as follows: Eight studies were at evidence Level 1, seven were at Level 2, two were at Level 3, and one was at Level 4.

Conclusions:

Our review suggests that there is preliminary support for the benefits of exercise and physical activity in Huntington’s disease in terms of motor function, gait speed, and balance, as well as a range of physical and social benefits identified through patient-reported outcomes. Variability in mode of intervention as well as outcome measures limits the interpretability of these studies, and high-quality studies that incorporate adaptive trial designs for this rare disease are needed.

Rating Scales and Performance-based Measures for Assessment of Functional Ability in Huntington's Disease: Critique and Recommendations

Limitation of functional ability is a major feature of Huntington's disease (HD). The International Parkinson and Movement Disorder Society (MDS) commissioned the appraisal of the use and clinimetric properties of clinical measures of functional ability that have been applied in HD studies and trials to date, to make recommendations regarding their use based on standardized criteria. After a systematic literature search, we included a total of 29 clinical measures grouped into two categories: (1) performance-based measures (e.g., balance, walking, and reaching/grasping), and (2) rating scales. Three performance-based measures are rated as "recommended": the Tinetti Mobility Test for screening of fall risk and for severity assessment of mobility in patients with manifest HD (up to stage III); the Berg Balance Scale for severity of balance impairment; and the Six-Minute Walk Test for assessment of walking endurance (severity) in HD subjects with preserved ambulation. No rating scale targeting functional ability reached a "recommended" status either for screening or severity measurement. The main challenges identified in this review include applying widely accepted conceptual frameworks to the identified measures, the lack of validation of clinical measures to detect change over time, and absence of validated measures for upper limb function. Furthermore, measures of capacity or ability to perform activities of daily living had ceiling effects in people with early and pre-manifest HD. We recommend that the MDS prioritize the development of new scales that capture small, but meaningful changes in function over time for outcome assessment in clinical trials, particularly in earlier stages of HD.

Physical therapy and exercise interventions in Huntington's disease: a mixed methods systematic review protocol

REVIEW QUESTION/OBJECTIVE

The review seeks to evaluate the effectiveness of physical therapy and exercise interventions in Huntington's disease (HD). The review question is: What is the effectiveness of physiotherapy and therapeutic exercise interventions in people with HD, and what are patients', families' and caregivers' perceptions of these interventions?The specific objectives are:This mixed methods review seeks to develop an aggregated synthesis of quantitative, qualitative and narrative systematic reviews on physiotherapy and exercise interventions in HD, in an attempt to derive conclusions and recommendations useful for clinical practice and policy decision-making.

Quality of Life in Huntington's Disease: Critique and Recommendations for Measures Assessing Patient Health-Related Quality of Life and Caregiver Quality of Life

The compromise of quality of life in Huntington's disease is a major issue, both for individuals with the disease as well as for their caregivers. The International Parkinson and Movement Disorder Society commissioned a review of the use and clinimetric validation status of measures used in Huntington's disease to assess aspects related with quality of life and to make recommendations on their use following standardized criteria. We included both patient-centered measures (patient health-related quality-of-life measures) and caregiver-centered measures (caregiver quality-of-life measures). After conducting a systematic literature search, we included 12 measures of patient health-related quality of life and 2 measures of caregiver quality of life. Regarding patient-centered measures, the Medical Outcomes Study 36-Item Short-Form Health Survey is "recommended" as a generic assessment of health-related quality of life in patients with Huntington's disease. The 12-Item Short Form Health Survey, the Sickness Impact Profile, the 12-item World Health Organization Disability Assessment Schedule, and the Huntington's Disease Health-Related Quality of Life questionnaire are "suggested." No caregiver-centered quality-of-life measure obtained a "recommended" status. The Alzheimer's Carer's Quality of Life Inventory and the Huntington's Disease Quality of Life Battery for Carers are "suggested." Recognizing that the assessment of patient health-related quality of life can be challenging in Huntington's disease, as patients may lack insight and there is insufficient clinimetric testing of these scales, the committee concluded that further validation of currently available health-related quality-of-life measures should be undertaken, namely, those Huntington's disease-specific health-related quality-of-life measures that have recently been reported and used. © 2018 International Parkinson and Movement Disorder Society.

The influence of motor ability rehabilitation on temporal-spatial parameters of gait in Huntington's disease patients on the basis of a three-dimensional motion analysis system: An experimental trial

OBJECTIVE

There is no existing standard, evidence-based, scientific model for motor ability improvement in Huntington's Disease (HD) patients aimed at maintaining independent gait for as long as possible, or performing activities of daily living, the effectiveness of which would be supported by the results of studies using objective research tools. Under these circumstances, the aim of this study was to analyze the influence of motor ability rehabilitation on the spatial-temporal parameters of gait in HD patients.

DESIGN

It was an experimental trial. The studied group consisted of 30 patients (17 women and 13 men) with HD. In hospital conditions, the patients participated in the 3-week motor ability l rehabilitation programme tailored to individual needs. The study group was tested using the Vicon 250 three-dimensional gait analysis system before and after the physical exercise programme.

RESULTS

Walking speed after therapy increased for the left lower limb from 1.06 (SD 0.24) [m/s] to 1.21 (SD 0.23) [m/s], and for the right lower limb from 1.07 (SD 0.25) [m/s] to 1.20 (SD 0.25) [m/s]. The cycle length increased after the applied therapy for the left lower limb from 1.17 (SD 0.20) [m] to 1.23 (SD 0.19) [m].

CONCLUSION

The three-week motor ability rehabilitation programme positively influences spatial-temporal gait parameters in HD patients.

The Role of Rehabilitation in Patients With Progressive Supranuclear Palsy: A Narrative Review

Progressive supranuclear palsy (PSP) is a progressive neurodegenerative disorder caused by the deposition of abnormal proteins in neurons of the basal ganglia that limit motor ability, resulting in disability and reduced quality of life. So far, no pharmacologic therapy has been developed, and the treatment remains symptomatic. The aim of the present study is to perform a systematic investigation of the literature, and to determine the types and effects of rehabilitative interventions used for PSP. A search of all studies was conducted in MEDLINE/PubMed, the Cochrane Central Register of Controlled Trials, CINAHL, and EMBASE. Twelve studies were identified, including 6 case reports, 3 case series, one case-control study, one quasi-randomized trial (i.e. not truly random) with crossover design, and one randomized controlled trial, with 88 patients investigated overall. Rehabilitative interventions varied in type, number, frequency, and duration of sessions. The most commonly used clinical measures were the Progressive Supranuclear Palsy Rating Scale (PSPRS) and Unified Parkinson's Disease Rating Scale (UPDRS). Physical exercises were the main rehabilitative strategy but were associated with other interventions and rehabilitative devices, in particular treadmill and robot-assisted gait training. All studies showed an improvement in balance and gait impairment with a reduction of falls after rehabilitation treatment. Because of poor methodological quality and the variety of rehabilitative approaches including different and variable strategies, there was insufficient evidence of the effectiveness of any specific rehabilitation intervention in PSP. Despite this finding, rehabilitation might improve balance and gait, thereby reducing falls in PSP patients.

LEVEL OF EVIDENCE

IV.

Gait, balance, and falls in Huntington disease

Huntington disease (HD) is an autosomal-dominant, progressive, neurodegenerative disorder, characterized by involuntary movements and other motor impairments, cognitive/behavioral symptoms, and psychiatric disorders. Gait and balance impairments and falls greatly impact on the quality of life among people with HD, and being fall-prone is one of the strongest predictors of nursing-home placement. Gait impairment in HD is characterized by bradykinesia, reduced velocity, and increased variability in spatiotemporal features. Detrimental changes in symmetry, step length, stride time, balance measures, gait adaptability (external cues, dual tasking), and hypo/hyperkinesia have also been observed. Balance impairment is characterized by impairments of anticipatory balance without a change in base of support, anticipatory balance with a change in base of support, and reactive balance. In addition to gait and balance impairment, people with HD have a range of intrinsic and extrinsic factors that increase fall risk, including reduced cognitive reserve for dual tasking. Currently there is some evidence to suggest exercise interventions can address some HD-specific gait and balance deficits. However, no intervention studies to date have specifically targeted falls. Large, well-designed, randomized controlled trials are needed to guide future fall prevention interventions in people with HD.

Induced neural stem cells as a means of treatment in Huntington's disease

INTRODUCTION

Huntington's disease (HD) is an inherited neurodegenerative disease characterized by chorea, dementia, and depression caused by progressive nerve cell degeneration, which is triggered by expanded CAG repeats in the huntingtin (Htt) gene. Currently, there is no cure for this disease, nor is there an effective medicine available to delay or improve the physical, mental, and behavioral severities caused by it. Areas covered: In this review, the authors describe the use of induced neural stem cells (iNSCs) by direct conversion technology, which offers great advantages as a therapeutic cell type to treat HD. Expert opinion: Cell conversion of somatic cells into a desired stem cell type is one of the most promising treatments for HD because it could be facilitated for the generation of patient-specific neural stem cells. The induced pluripotent stem cells (iPSCs) have a powerful potential for differentiation into neurons, but they may cause teratoma formation due to an undifferentiated pluripotent stem cell after transplantation Therefore, direct conversion of somatic cells into iNSCs is a promising alternative technology in regenerative medicine and the iNSCs may be provided as a therapeutic cell source for Huntington's disease.

Understanding leisure-time physical activity: Voices of people with MS who have moderate-to-severe disability and their family caregivers

Background

Physical activity (PA) is beneficial for all people, yet people affected by multiple sclerosis (MS) find regular PA challenging. These people may include individuals with the disease who have moderate‐to‐severe disability and their family caregivers. For researchers and clinicians to effectively promote PA among caregiver/care‐recipient dyads with moderate‐to‐severe MS, a comprehensive understanding of the shared PA experiences of these dyads would be beneficial.

Objective

We explored shared experiences of caregiver/care‐recipient dyads affected by moderate‐to‐severe MS about PA and directions for intervention.

Methods

Six focus groups with 23 people with moderate‐to‐severe MS and 12 family caregivers were conducted. Data were analysed using a constant comparative approach.

Results

Three major themes emerged as follows: (i) PA is a continuum, (ii) cycle of disengagement and (iii) cycle of adjustment. The first theme captured the dyads understanding that PA falls along a continuum ranging from highly structured to unstructured activities. Cycle of disengagement captured the experiences of dyads engaging in little or no PA. These dyads perceived internal and external issues as drivers of the cycle of disengagement, while availability of supportive programmes and services or people helped the dyads to break out of the cycle. When the cycle of disengagement was broken, the dyads described moving towards the cycle of adjustment, where they were able to learn skills and take action to incorporate PA into daily routines.

Conclusion

This research highlights the need to adopt an integrative approach that acknowledges the caregiver/care‐recipient dyad with moderate‐to‐severe MS as a focus for PA intervention.

Feasibility and Pilot Studies in Palliative Care Research: A Systematic Review

CONTEXT

Feasibility and pilot study designs are common in palliative care research. Finding standard guidelines on the structure and reporting of these study types is difficult.

OBJECTIVES

In feasibility and pilot studies in palliative care research, to determine 1) how commonly a priori feasibility are criteria reported and whether results are subsequently reported against these criteria? and 2) how commonly are participants' views on acceptability of burden of the study protocol assessed?

METHODS

Four databases (OVID Medline, EMBASE, CINAHL, and PubMed via caresearch.com.au.) were searched. Search terms included palliative care, terminal care, advance care planning, hospice, pilot, feasibility, with a publication date between January 1, 2012 and December 31, 2013. Articles were selected and appraised by two independent reviewers.

RESULTS

Fifty-six feasibility and/or pilot studies were included in this review. Only three studies had clear a priori criteria to measure success. Sixteen studies reported participant acceptability or burden with measures. Forty-eight studies concluded feasibility.

CONCLUSION

The terms "feasibility" and "pilot" are used synonymously in palliative care research when describing studies that test for feasibility. Few studies in palliative care research outline clear criteria for success. The assessment of participant acceptability and burden is uncommon. A gold standard for feasibility study design in palliative care research that includes both clear criteria for success and testing of the study protocol for participant acceptability and burden is needed. Such a standard would assist with consistency in the design, conduct and reporting of feasibility and pilot studies.

Physical Activity Self-Management and Coaching Compared to Social Interaction in Huntington Disease: Results From the ENGAGE-HD Randomized, Controlled Pilot Feasibility Trial

BACKGROUND

Self-management and self-efficacy for physical activity is not routinely considered in neurologic rehabilitation.

OBJECTIVE

This study assessed feasibility and outcomes of a 14-week physical activity self-management and coaching intervention compared with social contact in Huntington disease (HD) to inform the design of a future full-scale trial.

DESIGN

Assessor blind, multisite, randomized pilot feasibility trial.

SETTING

Participants were recruited and assessed at baseline, 16 weeks following randomization, and then again at 26 weeks in HD specialist clinics with intervention delivery by trained coaches in the participants' homes.

PATIENTS AND INTERVENTION

People with HD were allocated to the ENGAGE-HD physical activity coaching intervention or a social interaction intervention.

MEASUREMENTS

Eligibility, recruitment, retention, and intervention participation were determined at 16 weeks. Other outcomes of interest included measures of mobility, self-efficacy, physical activity, and disease-specific measures of motor and cognition. Fidelity and costs for both the physical activity and social comparator interventions were established.

RESULTS

Forty percent ( n = 46) of eligible patients were enrolled; 22 were randomized to the physical intervention and 24 to social intervention. Retention rates in the physical intervention and social intervention were 77% and 92%, respectively. Minimum participation criteria were achieved by 82% of participants in the physical intervention and 100% in the social intervention. There was no indication of between-group treatment effects on function; however, increases in self-efficacy for exercise and self-reported levels of physical activity in the physical intervention lend support to our predefined intervention logic model.

LIMITATIONS

The use of self-report measures may have introduced bias.

CONCLUSIONS

An HD physical activity self-management and coaching intervention is feasible and worthy of further investigation.

Feasibility of computerized working memory training in individuals with Huntington disease

Objectives

Huntington disease (HD) is associated with a variety of cognitive deficits, with prominent difficulties in working memory (WM). WM deficits are notably compromised in early-onset and prodromal HD patients. This study aimed to determine the feasibility of a computerized WM training program (Cogmed QM), novel to the HD population.

Methods

Nine patients, aged 26–62, with early stage HD underwent a 25-session (5 days/week for 5 weeks) WM training program (Cogmed QM). Training exercises involved the manipulation and storage of verbal and visuospatial information, with difficulty adapted as a function of individual performance. Neuropsychological testing was conducted before and after training, and performance on criterion WM measures (Digit Span and Spatial Span), near-transfer WM measures (Symbol Span and Auditory WM), and control measures were evaluated. Post-training interviews about patient experience were thematically analyzed using NVivo software.

Results

Seven of nine patients demonstrated adherence to the training and completed all sessions within the recommended timeframe of 5 weeks. All adherent patients showed improvement on the Cogmed tasks as defined by the Improvement Index (M = 22.17, SD = 8.84, range = 13–36). All adherent patients reported that they found training helpful (n = 7), and almost all felt that their memory improved (n = 6). Participants also expressed that the training was difficult, sometimes frustrating, and time consuming.

Conclusions

This pilot study provides support for feasibility of computerized WM training in early-stage patients with HD. Results suggest that HD patients perceive benefits of intensive WM training, though a full-scale and controlled intervention project is needed to understand the size of the effect and reliability of changes over time.

Trial registration

ClinicalTrials.gov, Registry number NCT02926820

Rehabilitation training in neural restitution

Over the last decade, neural transplantation has emerged as one of the more promising, albeit highly experimental, potential therapeutics in neurodegenerative disease. Preclinical studies in rat lesion models of Huntington's disease (HD) and Parkinson's disease (PD) have shown that transplanted precursor neuronal tissue from a fetus into the lesioned striatum can survive, integrate, and reconnect circuitry. Importantly, specific training on behavioral tasks that target striatal function is required to encourage functional integration of the graft to the host tissue. Indeed, "learning to use the graft" is a concept recently adopted in preclinical studies to account for unpredicted profiles of recovery posttransplantation and is an emerging strategy for improving graft functionality. Clinical transplant studies in HD and PD have resulted in mixed outcomes. Small sample sizes and nonstandardized experimental procedures from trial to trial may explain some of this variability. However, it is becoming increasingly apparent that simply replacing the lost neurons may not be sufficient to ensure the optimal graft effects. The knowledge gained from preclinical grafting and training studies suggests that lifestyle factors, including physical activity and specific cognitive and/or motor training, may be required to drive the functional integration of grafted cells and to facilitate the development of compensatory neural networks. The clear implications of preclinical studies are that physical activity and cognitive training strategies are likely to be crucial components of clinical cell replacement therapies in the future. In this chapter, we evaluate the role of general activity in mediating the physical ability of cells to survive, sprout, and extend processes following transplantation in the adult mammalian brain, and we consider the impact of general and specific activity at the behavioral level on functional integration at the cellular and physiological level. We then highlight specific research questions related to timing, intensity, and specificity of training in preclinical models and synthesize the current state of knowledge in clinical populations to inform the development of a strategy for neural transplantation rehabilitation training.

The role of rehabilitation therapy in Huntington disease

The role of rehabilitation interventions is increasingly considered a key component to effective management of people with Huntington disease (HD). Lifestyle factors, such as activity level and exercise, as well as specific motor training may be helpful in managing the functional sequelae of HD and possibly slowing disease progression. In this chapter, we focus on the role of rehabilitation therapy in secondary and tertiary prevention of the potentially devastating consequences of HD. We provide a brief overview of the range of motor and cognitive impairments in HD and their effect on functional abilities. We further discuss emerging evidence in terms of the role of exercise, physical activity, and physical therapies in helping to minimize functional loss and maximize quality of life throughout the disease process. Future directions with respect to intensive and goal-directed exercise, including aerobic and strengthening programs, are also discussed. This is an area of particular importance alongside exploring the potential that motor-training paradigms have in mediating the effects of disease-modifying drugs, cell replacement therapy, or genetic manipulations, when available.

A randomized, controlled trial of a multi-modal exercise intervention in Huntington's disease

INTRODUCTION

This study aimed to evaluate the feasibility and benefit of a structured exercise intervention in people with Huntington's Disease (HD).

METHODS

This study was conducted at 6 sites, and participants were randomized into either exercise or control (usual care) groups, and were assessed at baseline, 13 and 26 weeks. The intervention was a 12 week, three times per week progressive exercise program, including aerobic (stationary cycling) and upper and lower body strengthening exercise with tapered 1:1 support for 20 of 36 sessions.

RESULTS

314 adults were assessed for eligibility: 248 did not meet inclusion criteria, 34 declined, and 32 were recruited and randomized. Three individuals in the intervention group were withdrawn within the first month due to concomitant medical conditions, resulting in 14 participants in intervention and 15 in control groups. There were two AEs in the intervention group, both related to previous medical conditions, and there were two SAEs, both in the control group. The intervention group had better fitness (predicted VO₂ max difference: 492.3 ml min^-1, 95% CI: [97.1, 887.6]), lower UHDRS mMS (difference 2.9 points, 95% [-5.42, -0.32]) and lower weight at Week 13 (difference 2.25 kg, 95% CI: [-4.47, -0.03]).

CONCLUSION

This study demonstrates that a short-term exercise intervention is safe and feasible. Individuals with HD may benefit from structured exercise, and intensity, monitoring and support may be key factors in optimizing response. Larger scale trials are now required to fully elucidate the extended clinical potential of exercise in HD.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN11392629.