Quality-of-life in Charcot-Marie-Tooth disease: the patient's perspective

Health-Related Quality of Life in Patients with Inherited Ataxia in Ireland

Inherited cerebellar ataxias (CA) are heterogeneous progressive neurological conditions associated with significant functional limitations. This study aimed to assess the implications of inherited CA on patients' self-reported quality of life (QoL) and impairments in work and activities. 129 individuals with ataxia responded to a survey focused on QoL. Health-related QoL was measured using the RAND 36-Item Short Form Survey. An adaptation of the validated Work Productivity and Activity Impairment questionnaire was used to assess the effect of health on work productivity and ability to perform activities over the past week. Nine percent of respondents were currently employed. Individuals with inherited ataxia experienced significant activity impairment, and 75% required professional or informal care. Health-related quality of life (HRQoL) was significantly worse in all areas for the individuals with inherited ataxia compared with Irish population normative values. Participants with Friedreich's ataxia (n = 56) demonstrated worse physical functioning then those with undetermined ataxia (n = 55). Female gender, younger age at symptom onset, current employment, retirement due to age or ataxia, and living in a long-term care facility were associated with higher sub-scores in different domains of HRQoL, while disease duration correlated with worse physical functioning sub-scores. This study is the first cross-sectional study on HRQoL in patients with inherited ataxia in Ireland. It highlights high rates of unemployment, difficulty with daily activities and physical functioning limitations, which is worse than comparative international studies. Given the limited therapeutic options currently available, optimising HRQoL is an important aspect of managing ataxia.

Patient- and caregiver-reported impact of symptoms in Duchenne muscular dystrophy

INTRODUCTION/AIMS

To better understand the disease burden faced by individuals with Duchenne muscular dystrophy (DMD) of all ages and elucidate potential targets for therapeutics, this study determined the prevalence and relative importance of symptoms experienced by individuals with DMD and identified factors associated with a higher disease burden.

METHODS

We conducted qualitative interviews with individuals with DMD and caregivers of individuals with DMD to identify potential symptoms of importance to those living with DMD. We subsequently performed a cross-sectional study to assess which symptoms have the highest prevalence and importance in DMD and to determine which factors are associated with a higher disease burden.

RESULTS

Thirty-nine individuals, aged 11 years and above, provided 3262 quotes regarding the symptomatic burden of DMD. Two hundred participants (87 individuals with DMD and 113 caregivers) participated in a subsequent cross-sectional study. Individuals with DMD identified limitations with mobility or walking (100%), inability to do activities (98.9%), trouble getting around (97.6%), and leg weakness (97.6%) as the most prevalent and life altering symptomatic themes in DMD. The symptomatic themes with the highest prevalence, as reported by caregivers on behalf of those with DMD for whom they care, were limitations with mobility or walking (90.3%), leg weakness (89.2%), and emotional issues (79.6%). Steroid/glucocorticoid use (e.g., prednisone or deflazacort) was associated with a lower level of disease burden in DMD.

DISCUSSION

There are many symptomatic themes that contribute to disease burden in individuals with DMD. These symptoms are identified by both individuals with DMD and their caregivers and have a variable level of importance and prevalence in the DMD population.

Gastrointestinal involvement in neuromuscular disorders

Although not often discussed, many of the neuromuscular disorders (NMDs) affect the gastrointestinal tract (GIT). Depending on the type of NMD, the prevalence of GIT involvement ranges from <5% (e.g. hereditary neuropathies, myofibrillar myopathies) to 100% (e.g. MNGIE, OPMD). Particularly in NMDs with multisystem affection, involvement of the GIT can dominate the clinical presentation or at least make up a significant part of the clinical picture. The most prominent representatives of NMDs with multisystem involvement are the mitochondrial disorders (MIDs) and the myotonic dystrophies. The best known syndromic MIDs with GIT involvement are MNGIE, MELAS, Leigh, and Pearson syndromes. Among neuropathies, GIT involvement is most commonly found in ALS and GBS. GIT involvement may also be a feature of myasthenia. The clinical manifestations of GIT involvement are diverse and can affect the entire GIT, from the teeth to the rectum, including the liver and pancreas. The most well-known clinical manifestations of GIT involvement are dysphagia, nausea, vomiting, reflux, hollow organ dysmotility, hepatopathy, diabetes, diarrhea, constipation, and fecal incontinence. Even if treatment can usually only be symptomatic, the therapeutic options are diverse, are often effective, and can significantly and beneficially influence the course of the underlying NMD.

Hyaluronic Acid-based Fillers for Facial Rehabilitation in Inherited Neuropath

Charcot-Marie-Tooth (CMT) disease is the most prevalent inherited neuromuscular disorder. It commonly leads to various musculoskeletal deformities, profoundly impacting the quality of life. The present case report explores the often under-recognized body image dissatisfaction in CMT, highlighting the potential benefits of a multidisciplinary approach to enhance aesthetic satisfaction. We present a case of a 54-year-old woman with CMT, who experienced chronic facial asymmetry, significantly impairing her quality of life. Seeking cosmetic enhancement, she underwent two sessions of facial treatment using hyaluronic acid-based fillers. The first session focused on correcting right mandibular hypoplasia and other facial asymmetries, whereas the second session focused on enhancing perioral aesthetics. The treatment resulted in significant aesthetic improvements, as demonstrated by high ratings in both the Physician Global Aesthetic Improvement Scale and the Subject Global Aesthetic Improvement Scale. Besides, there was a marked reduction in lip corner asymmetry, the patient's primary concern. The role of hyaluronic acid fillers in facial aesthetic enhancement is well established, and their application in the context of CMT is a promising under-investigated field, to our knowledge. This case study highlights the importance of considering body image in CMT patients and suggests that minimally invasive aesthetic procedures can be a valuable addition to the multidisciplinary care of patients with inherited neurological disorders. Despite being a single-case study, the significant improvement in the patient's aesthetic satisfaction requires further research in this field.

Patient-reported impact of symptoms in adrenoleukodystrophy (PRISM-ALD)

BACKGROUND

Adrenoleukodystrophy (ALD) is a multifaceted, X-linked, neurodegenerative disorder that comprises several clinical phenotypes. ALD affects patients through a variety of physical, emotional, social, and other disease-specific factors that collectively contribute to disease burden. To facilitate clinical care and research, it is important to identify which symptoms are most common and relevant to individuals with any subtype of ALD.

METHODS

We conducted semi-structured qualitative interviews and an international cross-sectional study to determine the most prevalent and important symptoms of ALD. Our study included adult participants with a diagnosis of ALD who were recruited from national and international patient registries. Responses were categorized by age, sex, disease phenotype, functional status, and other demographic and clinical features.

RESULTS

Seventeen individuals with ALD participated in qualitative interviews, providing 1709 direct quotes regarding their symptomatic burden. One hundred and nine individuals participated in the cross-sectional survey study, which inquired about 182 unique symptoms representing 24 distinct symptomatic themes. The symptomatic themes with the highest prevalence in the overall ALD sample cohort were problems with balance (90.9%), limitations with mobility or walking (87.3%), fatigue (86.4%), and leg weakness (86.4%). The symptomatic themes with the highest impact scores (on a 0-4 scale with 4 being the most severe) were trouble getting around (2.35), leg weakness (2.25), and problems with balance (2.21). A higher prevalence of symptomatic themes was associated with functional disability, employment disruption, and speech impairment.

CONCLUSIONS

There are many patient-relevant symptoms and themes that contribute to disease burden in individuals with ALD. These symptoms, identified by those having ALD, present key targets for further research and therapeutic development.

The Crohn's Disease-Health Index: Development and Evaluation of a Novel Outcome Measure

OBJECTIVE

We sought to develop and validate the Crohn's Disease-Health Index (CD-HI), a disease-specific, patient-reported outcome measure that serially measures Crohn's disease (CD) symptomatic burden in adults with CD.

BACKGROUND

As therapeutic interventions are tested among patients with CD, responsive outcome measures are needed to track disease progression and therapeutic gain during clinical trials.

PATIENTS AND METHODS

We conducted a national cross-sectional study of individuals with CD to identify the most prevalent and impactful symptoms of CD. The most relevant symptoms were included in the CD-HI. We used factor analysis, qualitative patient interviews, test-retest reliability evaluation, and known group validity testing to evaluate and optimize the CD-HI.

RESULTS

The CD-HI contains 12 subscales that comprehensively measure CD burden using the patient's perspective. Fifteen adults with CD beta tested the CD-HI and found the instrument to be clear, easy to use, and relevant to them. Twenty-three adults with CD participated in an assessment of test-retest reliability, which indicated high reliability of individual questions, subscales, and the full instrument (intraclass correlation coefficient = 0.84 for the full instrument). The CD-HI and its subscales demonstrated a high internal consistency (Cronbach α = 0.98 for the full instrument). The CD-HI distinguished between groups of individuals with CD known to differ in disease severity.

CONCLUSIONS

This research supports the use of the CD-HI as a valid, sensitive, reliable, and relevant patient-reported outcome to determine the multifactorial disease burden of those with CD, assess the relevance and merit of future CD therapies, and support drug labeling claims.

The Surgical Correction of Cavovarus Deformity in Charcot-Marie-Tooth Disease

Charcot-Marie-Tooth (CMT) disease is the most commonly inherited neuropathy. CMT disease is a motor-sensory neuropathy with multiple genotypes. By comparison, the phenotypic expression is more uniform, with two main presentations. Most patients who need surgical care have progressive cavovarus foot deformity, with muscle imbalance causing a nonplantigrade foot, soft-tissue contractures, and abnormal bone morphology. Surgical treatment can be life-changing for these patients, allowing them to walk potentially brace free with more endurance and less pain. Early realignment procedures may reduce progression of joint arthritis. A minority of patients have diffuse paralysis below the knee. These patients are best treated with ground-reaction ankle-foot orthoses. This review article is based on the senior author's extensive experience with CMT, along with the limited evidenced-based literature.

Patient Reported Outcomes Using Medical Cannabis for Managing Pain in Charcot-Marie-Tooth Disease

Objective: Chronic pain is a major problem for patients with Charcot-Marie-Tooth (CMT) disease. This exploratory study examined patient reported efficacy of medical cannabis for pain management in this population. Methods: Participants (N = 56; 71.4% female; Age = 48.9, SD = 14.6; 48.5% CMT1) were recruited though the Hereditary Neuropathy Foundation. The online survey contained 52 multiple choice questions about demographics, medical cannabis use, symptomology, efficacy, and adverse effects. Results: Nearly all (90.9%) of respondents reported experiencing pain, including all (100%) females and 72.7% of males (chi-square P < .05) with 91.7% of respondents indicating cannabis provided at least 50% pain relief. The most frequent response was an 80% reduction in pain. Moreover, 80.0% of respondents reported using less opiates, 69% noted using less sleep medication, and 50.0% reported using less anxiety/antidepressant medications. Negative side effects were noted by 23.5% of respondents. However, almost all (91.7%) of that subgroup did not have plans to stop consuming cannabis. One-third (33.9%) possessed a medical cannabis certificate. Patient perceptions of their physicians' attitudes regarding patient medical cannabis use greatly impacted whether respondents informed their providers of their usage. Conclusion: The vast majority of patients with CMT reported that cannabis was effective to manage pain symptoms. These data support the need for prospective, randomized, controlled trials using standardized dosing protocols to further delineate and optimize the potential use of cannabis to treat pain related to CMT.

Disease-specific wearable sensor algorithms for profiling activity, gait, and balance in individuals with Charcot-Marie-Tooth disease type 1A

BACKGROUND/AIMS

Charcot-Marie-Tooth Disease type 1A (CMT1A), the most common inherited peripheral neuropathy, is characterized by progressive sensory loss and weakness, which results in impaired mobility. Increased understanding of the genetics and pathophysiology of CMT1A has led to development of potential therapeutic agents, necessitating clinical trial readiness. Wearable sensors may provide useful outcome measures for future trials.

METHODS

Individuals with CMT1A and unaffected controls were recruited for this 12-month study. Participants wore sensors for in-clinic assessments and at-home, from which activity, gait, and balance metrics were derived. Mann-Whitney U tests were used to analyze group differences for activity, gait, and balance parameters. Test-retest reliability of gait and balance parameters and correlations of these parameters with clinical outcome assessments (COAs) were examined.

RESULTS

Thirty individuals, 15 CMT1A, and 15 controls, participated. Gait and balance metrics demonstrated moderate to excellent reliability. CMT1A participants had longer step durations (p < .001), shorter step lengths (p = .03), slower gait speeds (p < .001), and greater postural sway (p < .001) than healthy controls. Moderate correlations were found between CMT-Functional Outcome Measure and step length (r = -0.59; p = .02), and gait speed (r = 0.64; p = .01); 11 out of 15 CMT1A participants demonstrated significant increases in stride duration between the first and last quarter of the 6-min walk test, suggesting fatigue.

INTERPRETATION

In this initial study, gait and balance metrics derived from wearable sensors were reliable and associated with COAs in individuals with CMT1A. Larger longitudinal studies are needed to confirm our findings and evaluate sensitivity and utility of these disease-specific algorithms for clinical trial use.

Patient-reported impact of symptoms in lung cancer (PRISM-LC)

Background

Individuals with lung cancer (LC) face a variety of symptoms that significantly impact their lives. We use extensive patient input to determine the relative importance and prevalence of these symptoms and identify which demographic features are associated with a higher level of disease burden.

Methods

We performed semi-structured qualitative interviews with participants with LC to identify potentially important symptoms. We then conducted a cross-sectional study, in which participants rated the relative importance of 162 individual symptoms covering 14 symptomatic themes. Participant responses were analyzed by age, sex, disability status, disease duration, LC stage, type of treatment received, and smoking history, among other categories.

Results

Our cross-sectional study had 139 participants with LC. The most prevalent symptomatic themes reported by this population were fatigue (85.5%), impaired sleep and daytime sleepiness (73.5%), and emotional issues (73.0%). The symptomatic themes that had the greatest average impact (on a scale of 0 to 4, with 4 being the most impactful) were social role dissatisfaction (1.67), inability to do activities (1.64), and fatigue (1.60). Disability status had the strongest association with symptomatic theme prevalence. LC stage (stage IV), receipt of therapy, and smoking experience were also associated with higher frequency of symptomatic themes.

Conclusions

Individuals with LC face diverse and disease-specific symptoms that affect their daily lives. Patient insight on the prevalence and relative importance of these symptoms is invaluable to advance meaningful therapeutic interventions.

A Retrospective Bayesian Design of Experiment (B-DOE) on Drug Reposition Candidates for Treatment of Charcot-Marie-Tooth Neuropathy

Bayesian design of experiment (B-DOE) uses the principle of Bayesian Epistemology that explain the evidence as a logical-probalistic coherence on the basis of rational degrees of belief (or degrees of confidence). The researcher has design the (B-DOE) using Multilevel Hierarchy (MH), and data that may be obtained at the weak to moderate evidence level (literature, biological. Mechanism, computational and retrospective) may be helpful to identify bioactive compounds for treating (CMT) and provide the knowledge on pathogenesis, prognostic of the disease and collective mechanism of drug of action. The investigators will classify the evidence on the basis of hierarchy as moderate and weak, which will ultimately help to study new promising bioactive compounds potentially able to solve some of the issues related to CMT.

Patient-Reported Impact of Symptoms in Friedreich Ataxia

BACKGROUND AND OBJECTIVES

To determine the prevalence and relative importance of symptoms experienced by children and adults with Friedreich ataxia (FA) and to identify factors associated with a higher burden of disease.

METHODS

We conducted qualitative interviews with individuals with FA and caregivers of pediatric individuals with FA to identify potential symptoms of importance to those living with FA. We subsequently performed a cross-sectional study to assess which symptoms have the highest prevalence and importance in FA and to determine which factors are associated with a higher burden of disease.

RESULTS

Thirty-nine participants provided 2,527 quotes regarding the symptomatic burden of FA. Two hundred two individuals (153 individuals with FA and 49 caregivers) participated in a subsequent cross-sectional study. Individuals with FA and caregivers identified impaired coordination, limitations with mobility and walking, inability to do activities, fatigue, and lower extremity weakness as the most prevalent and life-altering symptomatic themes in FA. Muscle stiffness and functional staging for ataxia were associated with the prevalence of symptomatic themes in FA. In addition, the length of smaller GAA expansion and the mean length of both GAA expansions were strongly associated with the onset of symptoms in FA.

DISCUSSION

There are a wide variety of symptoms that affect the lives of individuals with FA. These symptoms, many underrecognized, have different levels of importance and occur at different rates in the FA population. The most common and life altering of these symptoms represent potential targets for future therapeutic interventions.

Effects of specialist care lower limb orthoses on personal goal attainment and walking ability in adults with neuromuscular disorders

BACKGROUND

Lower limb orthoses intend to improve walking in adults with neuromuscular disorders (NMD). Yet, reported group effects of lower limb orthoses on treatment outcomes have generally been small and heterogeneous. We propose that guideline-based orthotic care within a multidisciplinary expert setting may improve treatment outcomes.

AIM

To examine the effectiveness of specialist care orthoses compared to usual care orthoses on personal goal attainment and walking ability.

DESIGN

Cohort study.

POPULATION

Adults with NMD who experienced walking problems due to calf and/or quadriceps muscle weakness and were provided with a specialist care lower limb orthosis between October 2011 and January 2021.

METHODS

Three months after provision, the specialist care orthosis was compared to the usual care orthosis worn at baseline in terms of personal goal attainment (Goal Attainment Scaling (GAS)), comfortable walking speed (m/s), net energy cost (J/kg/m) (both assessed during a 6-minute walk test), perceived walking ability and satisfaction.

RESULTS

Sixty-four adults with NMD were eligible for analysis. The specialist care orthoses comprised 19 dorsiflexion-restricting ankle-foot orthoses (AFOs), 22 stance-control knee-ankle-foot orthoses (KAFOs) and 23 locked KAFOs. Overall, 61% of subjects showed a clinically relevant improvement in GAS score. Perceived safety, stability, intensity, fear of falling and satisfaction while walking all improved (p≤0.002), and subjects were satisfied with their specialist care orthosis and the services provided. Although no effects on walking speed or net energy cost were found in combined orthosis groups, specialist care AFOs significantly reduced net energy cost (by 9.5%) compared to usual care orthoses (from mean (SD) 3.81 (0.97) to 3.45 (0.80) J/kg/m, p = 0.004).

CONCLUSION

Guideline-based orthotic care within a multidisciplinary expertise setting could improve treatment outcomes in adults with NMD compared to usual orthotic care by improvements in goal attainment and walking ability. A randomized controlled trial is now warranted to confirm these results.

Treatment of Charcot-Marie-Tooth neuropathies

Charcot-Marie-Tooth (CMT) is a heterogeneous group of inherited neuropathies that affect the peripheral nerves and slowly cause progressive disability. Currently, there is no effective therapy. Patients' management is based on rehabilitation and occupational therapy, fatigue, and pain treatment with regular follow-up according to the severity of the disease. In the last three decades, much progress has been made to identify mutations involved in the different types of CMT, decipher the pathophysiology of the disease, and identify key genes and pathways that could be targeted to propose new therapeutic strategies. Genetic therapy is one of the fields of interest to silence genes such as PMP22 in CMT1A or to express GJB1 in CMT1X. Among the most promising molecules, inhibitors of the NRG-1 axis and modulators of UPR or the HDACs enzyme family could be used in different types of CMT.

Hereditary neuropathy

The hereditary neuropathies, collectively referred as Charcot-Marie-Tooth disease (CMT) and related disorders, are heterogeneous genetic peripheral nerve disorders that collectively comprise the commonest inherited neurological disease with an estimated prevalence of 1:2500 individuals. The field of hereditary neuropathies has made significant progress in recent years with respect to both gene discovery and treatment as a result of next-generation sequencing (NGS) approach. These investigations which have identified over 100 causative genes and new mutations have made the classification of CMT even more challenging. Despite so many different mutated genes, the majority of CMT forms share a similar clinical phenotype, and due to this phenotypic homogeneity, genetic testing in CMT is increasingly being performed through the use of NGS panels. The majority of patients still have a mutation in one the four most common genes (PMP22 duplication-CMT1A, MPZ-CMT1B, GJB1-CMTX1, and MFN2-CMT2A). This chapter focuses primarily on these four forms and their potential therapeutic approaches.

Disease Burden in Children With Spinal Muscular Atrophy: Results From a Large Cross-Sectional Study

Background:To facilitate advances in spinal muscular atrophy therapeutic research, it is important to determine the impact and prevalence of symptoms experienced by children with spinal muscular atrophy. Methods: We conducted qualitative interviews with caregivers of children with spinal muscular atrophy. From these interviews, we generated a survey inquiring about 260 symptoms of importance grouped into 17 symptomatic themes. Results: Sixteen caregivers of children with spinal muscular atrophy aged from 4 months to 12 years participated in initial interviews, and 77 caregivers completed the survey. Higher symptom prevalence was associated with spinal muscular atrophy type, SMN2 copy number, and functional status. Hip, thigh, or knee weakness had the greatest reported impact on the lives of children with spinal muscular atrophy. Conclusions: This research provides one of the largest data sets regarding disease burden in children with spinal muscular atrophy. The most prevalent symptoms are not identical to those with the greatest impact. This unique insight into the most impactful symptoms will help focus therapeutic development in spinal muscular atrophy.

Patient-Reported Impact of Symptoms in Crohn's Disease

INTRODUCTION

Patients with Crohn's disease (CD) experience a variety of symptoms that significantly affect their lives. In this study, we (i) ascertain the most prevalent and impactful symptoms in CD and (ii) identify modifying factors that are associated with a higher disease burden in CD.

METHODS

We conducted semistructured interviews with adult participants with CD to determine what issues have the greatest impact on their lives. Next, we conducted a large cross-sectional study of individuals with CD to determine the prevalence and relative importance of those symptoms and themes and to identify the demographic features that are associated with a higher disease burden.

RESULTS

Sixteen individuals with CD provided 792 direct quotes regarding their symptomatic burden. Four hundred three people with CD participated in our cross-sectional study. The symptomatic themes with the highest prevalence in CD were gastrointestinal issues (93.0%), fatigue (86.4%), dietary restrictions (77.9%), and impaired sleep or daytime sleepiness (75.6%). The symptomatic themes that had the greatest impact on patients' lives (0-4 scale) related to fatigue (1.82), impaired sleep or daytime sleepiness (1.71), gastrointestinal issues (1.66), and dietary restrictions (1.61). Symptomatic theme prevalence was strongly associated with a higher number of soft stools per day, greater number of bowel movements per day, missed work, employment and disability status, and having perianal disease.

DISCUSSION

Patients with CD experience numerous symptoms that affect their daily life. These symptoms, some underrecognized, vary based on disease and demographic characteristics and represent potential targets for future therapeutic interventions.

Management of Stress Urinary Incontinence With Pelvic Floor Muscle Training for a Woman With Charcot-Marie-Tooth Disease: A Case Report

Objective

The purpose of this report is to describe the effects of pelvic floor muscle training (PFMT) in stress urinary incontinence (SUI) of a woman with Charcot-Marie-Tooth (CMT) disease.

Clinical Features

A 50-year-old female patient with a diagnosis of type II CMT disease was referred to treatment as a result of a complaint of urinary loss upon effort (ie, coughing and sneezing). She reported that the symptoms started about 36 months prior. The urodynamic study revealed SUI with a Valsalva leak point pressure of 84 cmH₂O.

Intervention and Outcome

The treatment of SUI was carried out through a PFMT program for 12 weeks (with supervision) and exercises at home for another 12 weeks. A specialized physiotherapist measured symptoms and severity of SUI (3-day urinary diary, 1-hour pad test), pelvic floor muscle function (digital palpation, manometry and dynamometry), effect of the SUI on quality of life (Incontinence Quality of Life Questionnaire), and adherence to the outpatient sessions and to home exercise sets, which also were assessed (exercise diary).

Conclusion

In this patient with CMT disease, improvements in urinary symptoms and severity of SUI, pelvic floor muscle function, and effect of SUI on quality of life were noted after PFMT.

Patient-Reported Symptom Burden of Charcot-Marie-Tooth Disease Type 1A: Findings From an Observational Digital Lifestyle Study

OBJECTIVES

This study aims to explore the impact of Charcot-Marie-Tooth disease type 1A (CMT1A) and its treatment on patients in European (France, Germany, Italy, Spain, and the United Kingdom) and US real-world practice.

METHODS

Adults with CMT1A (n = 937) were recruited to an ongoing observational study exploring the impact of CMT. Data were collected via CMT&Me, an app through which participants completed patient-reported outcome measures.

RESULTS

Symptoms ranked with highest importance were weakness in the extremities, difficulty in walking, and fatigue. Almost half of participants experienced a worsening of symptom severity since diagnosis. Anxiety and depression were each reported by over one-third of participants. Use of rehabilitative interventions, medications, and orthotics/walking aids was high.

CONCLUSIONS

Patient-reported burden of CMT1A is high, influenced by difficulties in using limbs, fatigue, pain, and impaired quality of life. Burden severity appears to differ across the population, possibly driven by differences in rehabilitative and prescription-based interventions, and country-specific health care variability.

Valuing the "Burden" and Impact of Rare Diseases: A Scoping Review

Introduction: Rare diseases (RDs) are a severe, chronic, degenerative and often life-threatening group of conditions affecting more than 30 million people in Europe. Their impact is often underreported and ranges from psychological and physical symptoms seriously compromising quality of life. There is then a need to consolidate knowledge on the economic, social, and quality of life impacts of rare diseases.

Methods: This scoping review is the result of 9 qualitative interviews with experts and a literature search on Cost-of-Illness (COI) studies and quality of life (QoL) studies following the PRISMA methodology. Grey literature was also included to complement findings. Results. 63 COI studies were retrieved, covering 42 diseases and a vast majority of them using a prevalence-based approach (94%). All studies included medical costs, while 60% included non-medical costs, 68% productivity losses and 43% informal care costs. 56 studies on QoL were retrieved, mostly from Europe, with 30 different measurement tools. Grey literature included surveys from the pharmaceutical industry and patient organisations.

Discussion: The majority of studies evaluating the impact of RDs on the individual and society use the COI approach, mostly from a societal perspective. Studies often vary in scope, making them difficult to consolidate or compare results. While medical costs and productivity losses are consistently included, QoL aspects are rarely considered in COI and are usually measured through generic tools.

Conclusion: A comprehensive study on impact of rare disease across countries in Europe is lacking. Existing studies are heterogeneous in their scope and methodology and often lack a holistic picture of the impact of rare. Consensus on standards and methodology across countries and diseases is then needed. Studies that consider a holistic approach are often conducted by pharmaceutical companies and patient organisations exploring a specific disease area but are not necessarily visible in the literature and could benefit from the sharing of standards and best practices.

Accelerate Clinical Trials in Charcot-Marie-Tooth Disease (ACT-CMT): A Protocol to Address Clinical Trial Readiness in CMT1A

With therapeutic trials on the horizon for Charcot-Marie-Tooth type 1A (CMT1A), reliable, valid, and responsive clinical outcome assessments and biomarkers are essential. Accelerate Clinical Trials in CMT (ACT-CMT) is an international study designed to address important gaps in CMT1A clinical trial readiness including the lack of a validated, responsive functional outcome measure for adults, and a lack of validated biomarkers for multicenter application in clinical trials in CMT1A. The primary aims of ACT-CMT include validation of the Charcot-Marie-Tooth Functional Outcome Measure, magnetic resonance imaging of intramuscular fat accumulation as a lower limb motor biomarker, and in-vivo reflectance confocal microscopy of Meissner corpuscle sensory receptor density, a sensory biomarker. Initial studies have indicated that these measures are feasible, reliable and valid. A large prospective, multi-site study is necessary to fully validate and examine the responsiveness of these outcome measures in relation to existing outcomes for use in future clinical trials involving individuals with CMT1A. Two hundred 15 adults with CMT1A are being recruited to participate in this prospective, international, multi-center study. Serial assessments, up to 3 years, are performed and include the CMT-FOM, CMT Exam Score-Rasch, Overall Neuropathy Limitations Scale, CMT-Health Index, as well as nerve conduction studies, and magnetic resonance imaging and Meissner corpuscle biomarkers. Correlations using baseline data will be examined for validity. Longitudinal analyses will document the changes in function, intramuscular fat accumulation, Meissner corpuscle sensory receptor density. Lastly, we will use anchor-based and other statistical methods to determine the minimally clinically important change for these clinical outcome assessments and biomarkers in CMT1A. Reliable, and responsive clinical outcome assessments of function and disease progression biomarkers are urgently needed for application in early and late phase clinical trials in CMT1A. The ACT-CMT study protocol will address this need through the prospective, longitudinal, multicenter examination in unprecedented detail of novel and existing clinical outcome assessments and motor and sensory biomarkers, and enhance international clinical trial infrastructure, training and preparedness for future therapeutic trials in CMT and related neuropathies.

Employment status of patients with Charcot-Marie-Tooth type 1A

Previous studies showed that being unemployed is associated with lower quality of life in patients with Charcot-Marie-Tooth type 1A (CMT1A). The aim of this study was to assess the differences between CMT1A patients capable of working and CMT1A patients incapable of working due to CMT1A. Forty-four patients with genetically confirmed CMT1A were included. Medical Research Council (MRC) Sum Score, Charcot-Marie-Tooth Neuropathy Score (CMTNS), CMT Examination Score (CMTES), Overall Neuropathy Limitations Scale (ONLS), Beck Depression Inventory (BDI), Krupp's Fatigue Severity Scale (FSS), and Falls Efficacy Score (FES) were used. Whole cohort was divided into two groups: 1. CMT1A patients capable of working (employed and unemployed not due to CMT) and 2. CMT1A patients incapable of working due to CMT1A (unemployed due to CMT and retired due to CMT). At time of testing, 38.6% patients were employed, 13.6% were unemployed due to CMT, 6.8% were unemployed but not due to CMT, and 40.9% were retired early due to disability caused by CMT. Patients retired due to CMT1A at the age of 43 ± 10 years. ONLS total score and physical work appeared as significant independent predictors of being incapable of working due to CMT1A. Patients incapable of working were almost four times more likely to have fatigue (OR = 3.7, 95% CI 1.0-13.1, p < 0.05) and 11 times more likely to have fear of falling (OR = 11.0, 95% CI 2.0-59.7, p < 0.01). Patients with more severe functional disability and physical type of job were most likely incapable of working due to CMT1A. Incapability of working was associated with fatigue and fear of falling.

Patient reported quality of life in limb girdle muscular dystrophy

This study determined the frequency and impact of symptoms on quality of life in patients diagnosed with limb girdle muscular dystrophy (LGMD). Participants with a diagnosis of LGMD in registries based at the Coalition to Cure Calpain-3, the Jain foundation, and the Global FKRP Registry competed a survey to report the frequency and relative impact of themes and symptoms of LGMD. Frequency, mean impact, and population impact scores were calculated, and responses were categorized by age, symptom duration, gender, employment status, use of assistive devices, and LGMD subtypes. 134 participants completed the survey. The most prevalent themes included an inability to do activities (100%), limitation with mobility (99.3%), and lower extremity weakness (97.0%). Themes with the greatest impact were: limitations with mobility, lower extremity weakness, and an inability to do activities. Symptom duration and the use of assistive devices were associated with the presence of multiple themes. Employment was associated with the impact of several themes with no differences in frequency. The prevalence and impact of these themes vary in the LMGD population. The most prevalent and impactful themes were related to weakness, but additional concerns related to emotional challenges should also be considered in clinical and research settings.

Challenges in Treating Charcot-Marie-Tooth Disease and Related Neuropathies: Current Management and Future Perspectives

There is still no effective drug treatment available for Charcot-Marie-Tooth neuropathies (CMT). Current management relies on rehabilitation therapy, surgery for skeletal deformities, and symptomatic treatment of pain; fatigue and cramps are frequent complaints that are difficult to treat. The challenge is to find disease-modifying therapies. Several approaches, including gene silencing, to counteract the PMP22 gene overexpression in the most frequent CMT1A type are under investigation. PXT3003 is the compound in the most advanced phase for CMT1A, as a second-phase III trial is ongoing. Gene therapy to substitute defective genes or insert novel ones and compounds acting on pathways important for different CMT types are being developed and tested in animal models. Modulation of the Neuregulin pathway determining myelin thickness is promising for both hypo-demyelinating and hypermyelinating neuropathies; intervention on Unfolded Protein Response seems effective for rescuing misfolded myelin proteins such as P0 in CMT1B. HDAC6 inhibitors improved axonal transport and ameliorated phenotypes in different CMT models. Other potential therapeutic strategies include targeting macrophages, lipid metabolism, and Nav1.8 sodium channel in demyelinating CMT and the P2X7 receptor, which regulates calcium influx into Schwann cells, in CMT1A. Further approaches are aimed at correcting metabolic abnormalities, including the accumulation of sorbitol caused by biallelic mutations in the sorbitol dehydrogenase (SORD) gene and of neurotoxic glycosphingolipids in HSN1.

A double-blind, placebo-controlled, randomized trial of PXT3003 for the treatment of Charcot-Marie-Tooth type 1A

BACKGROUND

Charcot-Marie-Tooth disease type 1A (CMT1A) is a rare, orphan, hereditary neuromuscular disorder with no cure and for which only symptomatic treatment is currently available. A previous phase 2 trial has shown preliminary evidence of efficacy for PXT3003 in treating CMT1A. This phase 3, international, randomized, double-blind, placebo-controlled study further investigated the efficacy and safety of high- or low-dose PXT3003 (baclofen/naltrexone/D-sorbitol [mg]: 6/0.70/210 or 3/0.35/105) in treating subjects with mild to moderate CMT1A.

METHODS

In this study, 323 subjects with mild-to-moderate CMT1A were randomly assigned in a 1:1:1 ratio to receive 5 mL of high- or low-dose PXT3003, or placebo, orally twice daily for up to 15 months. Efficacy was assessed using the change in Overall Neuropathy Limitations Scale total score from baseline to months 12 and 15 (primary endpoint). Secondary endpoints included the 10-m walk test and other assessments. The high-dose group was discontinued early due to unexpected crystal formation in the high-dose formulation, which resulted in an unanticipated high discontinuation rate, overall and especially in the high-dose group. The statistical analysis plan was adapted to account for the large amount of missing data before database lock, and a modified full analysis set was used in the main analyses. Two sensitivity analyses were performed to check the interpretation based on the use of the modified full analysis set.

RESULTS

High-dose PXT3003 demonstrated significant improvement in the Overall Neuropathy Limitations Scale total score vs placebo (mean difference: - 0.37 points; 97.5% CI [- 0.68 to - 0.06]; p = 0.008), and consistent treatment effects were shown in the sensitivity analyses. Both PXT3003 doses were safe and well-tolerated.

CONCLUSION

The high-dose group demonstrated a statistically significant improvement in the primary endpoint and a good safety profile. Overall, high-dose PXT3003 is a promising treatment option for patients with Charcot-Marie-Tooth disease type 1A.

Health-related Quality of Life and Satisfaction with German Health Care Services in Patients with Charcot-Marie-Tooth Neuropathy

BackgroundCharcot-Marie-Tooth (CMT) neuropathies entail a large group of diseases with different gene mutation patterns, which produce heterogeneous phenotypes. Although health-related quality of life (HRQOL) is significantly impaired, a comprehensive assessment of HRQOL in CMT patients in Germany considering phenotypical heterogeneity represented a research gap.ObjectiveThe aim was to assess HRQOL and the satisfaction with health care in CMT patients in Germany.MethodsCMT patients >  15 years with a genetically confirmed CMT subtype were recruited through a national CMT patient registry. HRQOL was assessed using the EQ-5D-5L questionnaire. Furthermore, subjective impairments in daily or work activities and satisfaction with health care were assessed using 4-point scales.ResultsHRQOL in CMT patients (n = 385) was impaired compared to the German population. Most patients reported problems in the dimension mobility (89.6%), pain/discomfort (89.4%) and usual activities (81.0%). Except for patients with hereditary neuropathy with liability to pressure palsy (HNPP), we found no differences in HRQOL between the CMT subtypes. 72.0%of CMT patients were satisfied with available health care services. However, patients reported to expect more CMT-specific knowledge and support as well as easier prescription and cost coverage procedures from health professionals and insurances.ConclusionsThe patient-reported outcomes in the assessed CMT cohort elucidate the need for more specific health care services that also address the heterogeneous phenotypes. Although the assessment has been limited to the German health services setting, insights may be applicable to CMT-specific care in other national settings.

The impact of symptoms on daily life as perceived by patients with Charcot-Marie-Tooth type 1A disease

Introduction

In Charcot-Marie-Tooth type 1A (CMT1A) patients, daily life is mainly influenced by mobility and ambulation dysfunctions. The aim of our work was to evaluate the perception of disturbances that mostly impact on daily life in CMT1A patients and its difference on the basis of age, gender, disability, and quality of life.

Methods

Forty-one CMT1A patients underwent neurological assessment focused on establishing clinical disability through the Charcot-Marie-Tooth Neuropathy Score (CMTNS) and quality of life through the Short Form-36 (SF-36) questionnaire. We identified from CMT disturbances 5 categories [weakness in lower limbs (WLL), weakness in upper limbs (WUL), skeletal deformities (SD), sensory symptoms (SS), balance (B)] and patients classified the categories from the highest to the lowest impact on daily life (1: highest; 5: lowest). Ranking of the 5 categories, in the overall sample and in the different subgroups (dividing by gender, median of age and disease duration, CMTNS, domains of SF-36), was obtained and differences among subgroups were assessed using a bootstrap approach.

Results

Rank analysis showed that WLL was the most important disturbance on daily life whereas WUL had the lowest impact. In the older CMT1A group, the most important disturbance on daily life was B that was also the most relevant disturbance in patients with a greater disability. SD influenced daily life in younger patients. SS had less impact on daily life, with the exception of patients with a milder disability.

Discussion

Our findings demonstrated that the perception of disturbances that mostly impact on CMT1A patients’ daily life changes over the lifetime and with degree of disability.

MAM-36 and ABILHAND as outcome measures of multiple sclerosis hand disability: an observational study

BACKGROUND

Impaired upper limb functionality and dexterity are common in people with multiple sclerosis (PwMS) and lead to increased dependency and reduced quality of life.

AIM

The aim of this study was to compare the ability of the Manual Abilites Measure 36 (MAM-36) and the ABILHAND questionnaire to recognize an involvement of the upper limbs in PwMS, and to compare their results with those of other patient reported outcomes (PRO) evaluating disability, functional independence, symptoms of anxiety and depression, fatigue and quality of life.

DESIGN

The study design was observational.

SETTING

The setting of the study was outpatient.

POPULATION

The study population included fifty-one PwMS (mean age of 56.31 years, age range of 33-82 years, 72.5% of patients were females).

METHODS

For each patient were collected MAM-36, ABILHAND questionnaire, expanded disability status scale (EDSS), Functional Independence measure (FIM), Hospital Anxiety and Depression Scale (HADS), Modified Fatigue Impact Scale (MFIS) and Life Satisfaction Index (LSI).

RESULTS

A strong correlation between MAM-36 and the ABILHAND questionnaire (Spearman r: 0.79; P<0.0001) were found. We obtained a significant correlation between MAM-36 and EDSS (Spearman r: -0.5; P=0.0002), FIM (Spearman r: 0.55; P<0.0001); we did not observe a correlation with MFIS (Spearman r: -0.33; P=0.02); moreover we found a similar trend between ABILHAND and EDSS (Spearman r: -0.47; P=0.0005), FIM (Spearman r: 0.61; P<0.0001), MFIS (Spearman r: -0.41; P=0.002).

CONCLUSIONS

In PwMS the assessment of upper limbs is fundamental since it closely related to the level of disability of the person. Both MAM-36 and ABILHAND Questionnaire are equally able to detect upper limb dysfunctions in PwMS.

CLINICAL REHABILITATION IMPACT

Both MAM-36 and ABILHAND can be used for upper limbs evaluation, within a multidimensional approach that seems to be the best way to evaluate PwMS.

Specialised orthotic care to improve functioning in adults with neuromuscular disorders: protocol of a prospective randomised open-label blinded end-point study

INTRODUCTION

People suffering from leg muscle weakness caused by neuromuscular disorders (NMDs) are often provided with leg orthoses to reduce walking problems such as increased walking effort, diminished walking speed, reduced balance and falls. However, evidence for the effectiveness of leg orthoses to improve walking in this patient group is limited and there is an absence of standardised practice in orthotic prescription. In 2012 a Dutch multidisciplinary guideline was developed aimed to standardise the orthotic treatment process in NMD. Although application of the guideline in expert centres (specialised orthotic care) seems beneficial regarding clinical effectiveness, larger studies are necessary to confirm results and investigate cost-effectiveness. Therefore, this study aims to examine the effectiveness and cost-effectiveness of specialised orthotic care compared with usual orthotic care in adults with slowly progressive NMD.

METHODS AND ANALYSIS

A prospective randomised open-label blinded end-point study will be performed, in which 70 adults with slowly progressive NMD are randomly assigned to specialised orthotic care (intervention) or usual orthotic care (control). Outcome measures are assessed at baseline and at 3 and 6 months follow-up. The primary endpoints are gross walking energy cost (J/kg/m) assessed during a 6 min walk test and achievement of personal goals, measured with the Goal Attainment Scale. Secondary endpoints include walking speed, gait biomechanics, stability, physical functioning, falls and fear of falling, perceived fatigue and satisfaction. For the economic evaluation, societal costs and health-related quality of life will be assessed using cost questionnaires and the 5-Level version of EuroQol 5 Dimension, retrospectively.

ETHICS AND DISSEMINATION

The study is registered in the Dutch trial register (NL 7511) and the protocol has been approved by the Medical Ethics Committee of the Academic Medical Center in Amsterdam. Results will be presented at national and international scientific conferences and disseminated through peer-reviewed journals and media aimed at a broad audience including patients.

Rate of Changes in CMT Neuropathy and Examination Scores in Japanese Adult CMT1A Patients

Introduction: We aimed to clarify when adult patients with Charcot-Marie-Tooth disease type 1A (CMT1A), especially those diagnosed at middle or advanced ages, first showed symptoms and whether the rate of disease progression is accelerated by aging.

Methods: Medical records of CMT1A outpatients between 2012 and 2019 were reviewed. The age at diagnosis, age when symptoms first appeared, and rate of disease progression, assessed based on clinical outcome measures including the CMT Neuropathy Score (CMTNS), Rasch-modified CMTNS (CMTNS-R), CMT Examination Score (CMTES), and Rasch-modified CMTES (CMTES-R) were analyzed.

Results: Among 45 adult CMT1A patients, 42% had been diagnosed after 50 years of age, whereas 91% of all patients had exhibited some CMT-related symptoms before 20 years of age. The annual increase of all clinical outcome measures did not differ between patients under and over 50 years. Even when limited to patients whose initial CMTES-R showed mild to moderate severity, the rate of change in CMTES-R did not differ between the two age groups (the annual mean ± standard deviation, under 50 years: 1.1 ± 1.0, and over 50 years: 0.9 ± 1.1, p = 0.68). To determine whether patients with disabilities at a young age have a higher deterioration rate, they were classified into three groups according to their current age and age at diagnosis: patients under 50 years of age, patients over 50 years of age but diagnosed before 50, and patients diagnosed after 50 years of age. The mean annual increase of all clinical outcome measures, however, did not differ among these groups (CMTES-R: 1.03 ± 1.01 vs. 0.94 ± 1.57 vs. 0.81 ± 0.88, respectively, p = 0.87).

Discussion: CMT1A patients develop symptoms in childhood and adolescence even if such symptoms are not noticeable until reaching an advanced age. Deterioration rates of clinical outcome measures are constant irrespective of the age in their adulthood, although we cannot rule out the limitation that the difference did not reach significance because of the small number of patients. Being aware of the existence of a considerable number of undiagnosed CMT patients will help promote the avoidance of inadequate medication.

Translation and cross-cultural adaptation of the Charcot-Marie-Tooth disease Pediatric Scale to Brazilian Portuguese and determination of its measurement properties

BACKGROUND

The Charcot-Marie-Tooth disease Pediatric Scale (CMTPedS) has been used to measure aspects of disability in children with all types of Charcot-Marie-Tooth disease (CMT).

OBJECTIVE

To translate and cross-culturally adapt the CMTPedS into Brazilian-Portuguese and determine its reliability and validity.

METHODS

The translation and cross-cultural adaptation followed international guidelines recommendations. Twenty individuals with CMT were assessed. Two examiners assessed the participants for inter-rater reliability. Face validity was assessed by eight physical therapists that judged the relevance of each test item. The Bland-Altman analysis (bias) and standard error of measurement (SEM) complemented the analysis. Furthermore, intraclass correlation coefficients (ICC), weighted kappa (k), and internal consistency (Cronbach's alpha) was determined.

RESULTS

The CMTPedS was successfully translated and cross-culturally adapted. Twenty children/youth were enrolled in the study. Of these, the majority (55%) were girls with a mean age of 13.9 (range: from 6 to 18) years. Regarding face validity, the CMTPedS-Br showed relevant items for assessing children and youth with CMT. The ICC for the total score showed excellent reliability (ICC_2.1  = 0.93, 95% CI = 0.84, 0.97). The most reliable items were grip, dorsiflexion and plantar flexion strength while the least reliable items were pinprick, vibration, and gait. The internal consistency was excellent (α = 0.96, 95% CI = 0.91, 0.99) and the agreement showed small variability (bias = 0.15, 95% CI= -4.28, 4.60).

CONCLUSION

The CMTPedS-Br showed adequate reliability and face validity to measure disability in individuals with CMT. This tool will allow Brazil to be part of multicentered studies on such a rare but debilitating condition.

A Consensus Statement on the Surgical Treatment of Charcot-Marie-Tooth Disease

BACKGROUND

Charcot-Marie-Tooth (CMT) disease is a hereditary motor-sensory neuropathy that is often associated with a cavovarus foot deformity. Limited evidence exists for the orthopedic management of these patients. Our goal was to develop consensus guidelines based upon the clinical experiences and practices of an expert group of foot and ankle surgeons.

METHODS

Thirteen experienced, board-certified orthopedic foot and ankle surgeons and a neurologist specializing in CMT disease convened at a 1-day meeting. The group discussed clinical and surgical considerations based upon existing literature and individual experience. After extensive debate, conclusion statements were deemed "consensus" if 85% of the group were in agreement and "unanimous" if 100% were in support.

CONCLUSIONS

The group defined consensus terminology, agreed upon standardized templates for history and physical examination, and recommended a comprehensive approach to surgery. Early in the course of the disease, an orthopedic foot and ankle surgeon should be part of the care team. This consensus statement by a team of experienced orthopedic foot and ankle surgeons provides a comprehensive approach to the management of CMT cavovarus deformity.

LEVEL OF EVIDENCE

Level V, expert opinion.

Patient-reported impact of symptoms in Huntington disease: PRISM-HD

OBJECTIVE

To determine the frequency and relative importance of symptoms experienced by adults with Huntington disease (HD) and to identify factors associated with a higher disease burden.

METHODS

We performed 40 qualitative interviews (n = 20 with HD, n = 20 caregivers) and analyzed 2,082 quotes regarding the symptomatic burden of HD. We subsequently performed a cross-sectional study with 389 participants (n = 156 with HD [60 of whom were prodromal], n = 233 caregivers) to assess the prevalence and relative importance (scale 0-4) of 216 symptoms and 15 symptomatic themes in HD. Cross-correlation analysis was performed based on sex, disease duration, age, number of CAG repeats, disease burden, Total Functional Capacity score, employment status, disease status, and ambulatory status.

RESULTS

The symptomatic themes with the highest prevalence in HD were emotional issues (83.0%), fatigue (82.5%), and difficulty thinking (77.0%). The symptomatic themes with the highest relative importance to participants were difficulty thinking (1.91), impaired sleep or daytime sleepiness (1.90), and emotional issues (1.81). High Total Functional Capacity scores, being employed, and having prodromal HD were associated with a lower prevalence of symptomatic themes. Despite reporting no clinical features of the disease, prodromal individuals demonstrated high rates of emotional issues (71.2%) and fatigue (69.5%). There was concordance between the prevalence of symptoms reported by manifest individuals and caregivers.

CONCLUSIONS

Many symptomatic themes affect the lives of those with HD. These themes have a variable level of importance to the HD population and are identified both by those with HD and by their caregivers.

Are we prepared for clinical trials in Charcot-Marie-Tooth disease?

There has been considerable progress in developing treatments for Charcot-Marie-Tooth disease with a number of therapies either completing or nearing clinical trials. In the case of CMT1A, the commonest subtype of CMT, there have been more than five randomised, double blind placebo-controlled trials. Although these trials were negative for the primary outcome measure, considerable lessons have been learnt leading to the collection of large prospective natural history data sets with which to inform future trial design as well as the development of new and sensitive outcome measures. In this review we summarise the difficulties of conducting clinical trials in a slowly progressive disease such as CMT1A and the requirement for sensitive, reproducible and clinically relevant outcome measures. We summarise the current array of CMT specific outcome measures subdivided into clinical outcome measures, functional outcome measures, patient reported outcome measures, biomarkers of disease burden and treatment specific biomarkers of target engagement. Although there is now an array of CMT specific outcome measures, which collectively incorporate clinically relevant, sensitive and reproducible outputs, a single outcome measure incorporating all three qualities remains elusive.

Patient-Reported Symptoms in Facioscapulohumeral Muscular Dystrophy (PRISM-FSHD)

OBJECTIVE

To determine the frequency and relative importance of the most meaningful symptoms in facioscapulohumeral muscular dystrophy (FSHD) and to identify the demographic and clinical features that are associated with the greatest disease burden in this population.

METHODS

We performed a cross-sectional study involving 328 participants with FSHD. Collectively, participants reported the prevalence and relative importance of 274 symptoms and 15 symptomatic themes. We assessed the association between symptomatic theme prevalence and participants' age, sex, disease duration, pain level, employment status, and education.

RESULTS

Participants answered >48,000 questions regarding their disease burden. The symptomatic themes with the highest prevalence in our sample were problems with shoulders or arms (96.9%), limitations with activities (94.7%), core weakness (93.8%), fatigue (93.8%), limitations with mobility and walking (93.6%), changed body image due to the disease (91.6%), and pain (87.7%). Problems with shoulders and arms and limitations with mobility and walking had the greatest effect on participants' lives. Employment status and the report of pain had the most extensive association with the prevalence of symptoms, with employment being associated with 8 of 15 of the symptomatic themes and pain being associated with 7 of 15 of the symptomatic themes. Men and women with FSHD experienced a similar prevalence of all symptomatic themes.

CONCLUSIONS

Adults with FSHD experience a variety of symptoms that play an important role in their disease burden. These symptoms have a variable prevalence and importance in the FSHD population and are associated with disease duration, employment status, and pain level.

A painful foot with diagnostic and therapeutic consequences

Background A wide range of patients are referred to multidisciplinary pain clinics. An important part of the work-up is a thorough pain analysis that might reveal a specific cause for chronic pain. Method We describe a patient with chronic pain in one foot after a light trauma and repeated surgery. However, careful examination revealed symptoms and clinical finings in both feet. This led to referral to a University Hospital and the diagnosis of a chronic neurologic condition explaining both symptoms and findings. The diagnosis of this condition has implications both for further follow-up for this patient and possibly also other family members. Implications Professionals working in the pain-field should be aware of diagnosis that might partly explain increased pain or complications after surgery.

Foot Function Index: A Promising Questionnaire for Individuals With Charcot-Marie-Tooth Disease Type 1A

OBJECTIVE

To evaluate in a preliminary methodologic study, the Foot Function Index (FFI), a 3-subscale (pain, disability, and activity restriction) foot disability assessment questionnaire, in patients with Charcot-Marie-Tooth disease type 1A (CMT1A).

DESIGN

Monocentric exploratory cross-sectional study with 2 identical evaluations by the same physical medicine and rehabilitation physician at 14-day intervals (test-retest) according to international guidelines for validating health-related patient-reported outcomes, the Consensus-based Standards for the Selection of Health Measurement Instruments Criteria.

SETTING

Physical medicine and rehabilitation and neurology departments in a French academic hospital.

PARTICIPANTS

Patients with CMT1A confirmed by molecular biology (N=26).

INTERVENTION

The FFI and a health-related quality-of-life questionnaire (Medical Outcomes Study Short Form 36 [SF-36] with mental and physical composite scores) combined with quantitative walk analysis by instrumental gait analysis and evaluation of isokinetic quadriceps and hamstrings peak torque by isokinetic dynamometer.

MAIN OUTCOME MEASURES

FFI score and its dimensions.

RESULTS

Acceptability was satisfactory, with less than 5% missing data and good distribution of results. Internal consistency was very satisfactory, with Cronbach α of 0.95. Reproducibility was very satisfactory, with Lin concordance coefficient 0.82. External consistency was satisfactory, with expected correlation coefficients: the FFI was significantly correlated with the SF-36 physical composite score and gait parameters (cadence) (r=-0.58 and r=-0.52; P<.005) but not with peak torque or SF-36 mental composite score.

CONCLUSIONS

This study confirms the very good metrologic properties of the FFI in patients with CMT1A. The FFI could be a promising questionnaire to assess foot-related disability in a neurologic disease. Complementary studies are still needed to confirm these promising preliminary results.

Cost of illness in Charcot-Marie-Tooth neuropathy: Results from Germany

OBJECTIVE

To assess cost associated with the disease-specific need of patients diagnosed with Charcot-Marie-Tooth neuropathies (CMT) in Germany.

METHODS

Patients with CMT were identified through the national patient registry and invited to complete a standardized questionnaire. The data collected include information about health care use, informal care, and other disease-related expenses as well as the working situation. Based on this information, we estimated the annual cost of CMT from the perspective of society.

RESULTS

This study included 397 patients with a genetically confirmed CMT diagnosis. We estimated total annual cost of illness (COI) of $22,362 (95% CI $19,464-$25,723) per patient, of which 67.3% were direct costs. The highest single cost factor was informal care cost. For Germany, we extrapolated total cost of CMT of $735.0 million ($639.8 million-$845.5 million). Multivariate regression analysis showed that total annual cost increased with disease severity (Charcot-Marie-Tooth Neuropathy Score). Age, CMT subtype, comorbidities, body mass index, and employment status were also predictors of a change in cost (p < 0.05). Moreover, we found differences in total cost depending on marital status, subjectively evaluated impairments, dependence on other persons, care level, educational level, and disease duration.

CONCLUSIONS

CMT is associated with a substantial economic burden. For the first time, the COI of CMT has been assessed and will serve as important input to decision-making in health policy, especially regarding research and development of therapies. Moreover, our results indicate the importance of the patient-reported perception of disease severity related to the consumption of resources.

Walking Speed Is Correlated With the Isokinetic Muscular Strength of the Knee in Patients With Charcot-Marie-Tooth Type 1A

Charcot-Marie-Tooth disease type 1A is the most common hereditary neuropathy. Affected individuals have a distal motor deficit, initially affecting the lower limbs and impairing walking performance. Isokinetic dynamometry can be used to objectively assess muscle strength of patients with neuromuscular disorders. No studies have evaluated the effect of muscle strength deficits of knee extensors and flexors on walking parameters for patients with Charcot-Marie-Tooth disease type 1A. The purpose of this study was to determine correlations between the isokinetic muscular strength of knee flexors and knee extensors and walk parameters for patients with Charcot-Marie-Tooth disease type 1A. isokinetic muscular strength of the knee was assessed on an isokinetic dynamometer (Cybex) and walking by instrumented walkway analysis (GaitRite). We included 33 patients (23 females, mean ± SD age 46.7 ± 13.3 yrs, mean ± SD body mass index 25.7 ± 4.6 kg/m). We found a correlation between walking speed and isokinetic muscular strength of knee extensors for the entire population and between walking speed and isokinetic muscular strength of knee extensors and knee flexors for patients younger than 50 yrs. Isokinetic dynamometry can provide objective measures of knee muscle strength, which is correlated with walking speed but not cadence or step/stride length of patients with Charcot-Marie-Tooth disease.

Patient Reported Impact of Symptoms in Spinal Muscular Atrophy (PRISM-SMA)

OBJECTIVE

To determine the frequency and relative importance of symptoms experienced by adults with spinal muscular atrophy (SMA) and to identify factors that are associated with a higher burden of disease in this population.

METHODS

We conducted a cross-sectional study of 359 adults with SMA using the International SMA Patient Registry. Participants provided input regarding 20 symptomatic themes and 207 symptoms that potentially affect adults with SMA. Participants were asked about the relative importance of each symptom, and analysis was conducted to determine how age, sex, SMA type, education, mobility, and employment status relate to symptom prevalence.

RESULTS

Limitations with mobility or walking (98.6%) and the inability to do activities (98.6%) were the 2 themes with the highest prevalence in the study sample. Limitation with mobility or walking was the theme that was identified as having the greatest effect on the lives of adults with SMA. Employment status was associated with the prevalence of 4 of 20 themes and a reliance on an assistive device was associated with 7 of 20 themes. The prevalence of breathing difficulties, choking or swallowing difficulties, and communication difficulties differed among those with different SMA types.

CONCLUSIONS

There are many symptomatic themes that affect the lives of adults with SMA. These themes vary in prevalence and relative importance in the adult SMA population.

The Charcot-Marie-Tooth Functional Outcome Measure (CMT-FOM)

OBJECTIVE

The purpose of this study was to examine the feasibility, reliability, and convergent validity of the Charcot-Marie-Tooth Functional Outcome Measure (CMT-FOM), a new performance-based measure assessing functional ability in adults with CMT disease.

METHODS

Adults with CMT type 1A (CMT1A) were recruited at the Universities of Rochester and Iowa. Participants were assessed using the CMT-FOM, CMT Exam Score (CMTES), and a symptom report. Test-retest reliability was examined using intraclass correlation coefficients, internal consistency using Cronbach α, and convergent and known-groups validity using Spearman rank analysis and the Mann-Whitney test.

RESULTS

Forty-three individuals (70% women; mean age 41, SD 14.9 years) participated. The CMT-FOM (mean 25.3 ± 8.7, range 12-44/52) was moderately correlated with the CMTES (ρ = 0.62; p < 0.0001) and exhibited acceptable reliability (intraclass correlation coefficient = 0.92) and internal consistency (Cronbach α = 0.81). The CMT-FOM discriminated between participants with clinically mild vs moderate-severe CMT1A. Participants with the mildest CMT1A who demonstrated a floor effect on the CMTES showed functional limitations on the CMT-FOM.

CONCLUSIONS

The CMT-FOM is well tolerated and showed no floor/ceiling effects in an adult CMT1A cohort matching those likely to enter upcoming clinical trials. It appears to be reliable, and our data support convergent and known-groups validity in adults with CMT1A. Longitudinal studies further examining the psychometric properties of the CMT-FOM and its responsiveness to change before its application in therapeutic trials are necessary.

The Charcot-Marie-Tooth Health Index: Evaluation of a Patient-Reported Outcome

OBJECTIVE

The development of a disease-specific patient-reported outcome for Charcot-Marie-Tooth disease is an important step in the preparation for therapeutic trials. This study describes the development of the Charcot-Marie-Tooth Health Index (CMTHI).

METHODS

Inherited Neuropathy Consortium Contact Registry participants were queried on the symptoms that most impacted their lives. The CMTHI was developed based on these responses. Factor analysis, assessment of test-retest reliability, known group validity, and patient interviews were utilized to refine the instrument.

RESULTS

The final CMTHI contains 18 themes that capture Charcot-Marie-Tooth disease (CMT) burden. The CMTHI has a high internal consistency and test-retest reliability. The CMTHI was able to discriminate between patient groups expected to have different disease burden. The CMTHI was able to discriminate levels of disability as measured by the CMT examination score and the mobility-Disability Severity Index.

INTERPRETATION

The CMTHI represents a valid and reliable outcome to assess patient-reported disease burden in CMT. Ann Neurol 2018;84:225-233.

Outcome measures in the clinical evaluation of ambulatory Charcot-Marie-Tooth 1A subjects

BACKGROUND

The outcome measures (OMs) in clinical trials for Charcot-Marie-Tooth disease (CMT) still represent an issue. A recent study highlighted that three additional clinical OMs, the 10-Meter Walk Test (10MWT), the 9-Hole Peg Test, and foot dorsal flexion dynamometry, further improve discrimination between severely and mildly affected patients. Another study has recently assessed the validity and reliability of the 6-Minute Walk Test (6MWT).

AIM

The aim of this study was to identify the most useful scales in the clinical evaluation of CMT1A patients.

DESIGN

Observational study of the baseline data collected in a multicenter, prospective, randomized, single blind, controlled study to evaluate the efficacy and safety of an innovative rehabilitation protocol based on treadmill training, stretching, respiratory, and proprioceptive exercises (TreSPE study) in CMT1A patients.

SETTING

The outpatient service of the four Italian centers involved, which are specialized in hereditary neuropathies.

POPULATION

Fifty-three subjects with a clinical and genetically confirmed diagnosis of CMT1A.

METHODS

At baseline, in addition to the CMT Neuropathy Score, all subjects underwent walking evaluation (6MWT, 10MWT), balance assessment (Berg Balance Scale [BBS], Short Physical Performance Battery [SPPB]) and a subjective evaluation of quality of life (SF36) and walking ability (Walk12).

RESULTS

Analyzing the baseline data, as expected, we found a strong correlation between walk and balance evaluation, proving the validity of these tests in investigating the functional impairment of CMT1A subjects. Particularly, we found that subjects with better balance control walk at higher speed and perceive less limitations in their physical activities or motor skills. This can be reconducted to the fact that ankle stability depends upon different factors such as anatomy integrity, muscle strength and proprioception.

CONCLUSIONS

We identify the 6MWT, 10MWT, and SPPB as the most useful scales, in addition to the CMTNS, to evaluate the functional impairment of CMT1A patients who retain their walking capability and we suggest the use of SPPB because of its rapidity to assess balance and gait disorders in clinical settings.

CLINICAL REHABILITATION IMPACT

In the clinical practice it is important to evaluate patients comprehensively but rapidly. These outcome measures can help us to correctly assess balance and walking ability in CMT1A patients.

Targeting Heat Shock Protein 70 to Ameliorate c-Jun Expression and Improve Demyelinating Neuropathy

Increased expression of the c-jun transcription factor occurs in a variety of human neuropathies and is critical in promoting Schwann cell (SC) dedifferentiation and loss of the myelinated phenotype. Using cell culture models, we previously identified KU-32 as a novobiocin-based C-terminal heat shock protein 90 (Hsp90) inhibitor that decreased c-jun expression and the extent of demyelination. Additional chemical optimization has yielded KU-596 as a neuroprotective novologue whose mechanistic efficacy to improve a metabolic neuropathy requires the expression of Hsp70. The current study examined whether KU-596 therapy could decrease c-jun expression and improve motor function in an inducible transgenic model of a SC-specific demyelinating neuropathy (MPZ-Raf mice). Treating MPZ-Raf mice with tamoxifen activates the MAPK kinase pathway, increases c-jun expression and produces a profound demyelinating neuropathy characterized by a loss of motor function and paraparesis. KU-596 therapy did not interfere with MAPK activation but reduced c-jun expression, significantly improved motor performance, and ameliorated the extent of peripheral nerve demyelination in both prevention and intervention studies. Hsp70 was necessary for the drug's neuroprotective efficacy since MPZ-Raf × Hsp70 knockout mice did not respond to KU-596 therapy. Collectively, our data indicate that modulating Hsp70 may provide a novel therapeutic approach to attenuate SC c-jun expression and ameliorate the onset of certain demyelinating neuropathies in humans.

Balance and falls in people with Charcot-Marie-Tooth disease: A cohort survey

Aim:

To explore the relationship between balance deficit, falls, and activities of daily living in a cohort with Charcot-Marie-Tooth disease.

Method:

A cohort survey of individuals with Charcot-Marie-Tooth disease attending a neurogenetic clinic was carried out. Surveys were sent to individuals on a database of a state-wide neurogenetic service located in Perth, Australia.

Results:

Out of 71 surveys, 40 were returned (56%). The cohort were predominantly male (68%), the average age was 55.5 years (range 18–84) and average age at symptom onset was 23 years (range 5–65). Excluding skeletal foot changes, balance deficits (87.5%) and loss of balance confidence (90%) were the most frequently rated symptoms and those most severely affecting physical functioning (71% and 64% respectively). Ankle splinting was frequently reported in this population (65%). The majority of participants (69%) had fallen at least once in the past year and 40% of fallers reported having never seen a physiotherapist.

Conclusions:

Despite balance deficits and loss of balance confidence being frequently reported to impact daily activities, and falls and near-falls being common in this cohort with Charcot-Marie-Tooth disease, more than a third had not seen a physiotherapist. Future management to reduce the disease burden should investigate the effects of a timely multidisciplinary approach to manage balance dysfunction, and strategies to reduce falls in this population.

Patient-identified impact of symptoms in spinal and bulbar muscular atrophy

INTRODUCTION

The effects of spinal bulbar muscular atrophy (SBMA) on quality of life (QoL) are not well understood. This study describes symptoms from the patient's perspective and the impact these symptoms have on QoL.

METHODS

We conducted open-ended interviews with 21 adult men with genetically confirmed SBMA. Using a qualitative framework technique, we coded and analyzed interviews to identify symptoms and resulting themes.

RESULTS

From these interviews, 729 quotations were extracted. We identified 200 SBMA-specific symptoms and 20 symptomatic themes. Weakness was mentioned by all interviewees. Symptoms within the domain of mental health and the specific themes of emotional issues and psychological impact were also frequently mentioned.

DISCUSSION

Numerous symptoms affect QoL for patients with SBMA. We identified previously unrecognized symptoms that are important to address in enhancing clinical care for patients with SBMA and in developing tools to evaluate efficacy in future clinical trials. Muscle Nerve 57: 40-44, 2018.

Responsiveness of gait analysis parameters in a cohort of 71 CMT subjects

Detection of worsening in the slowly progressive Charcot-Marie-Tooth disease (CMT) is difficult. As previous clinical scales showed low responsiveness, novel outcome measures are under study, including innovative approaches such as quantitative muscle MRI and instrumented movement analysis. Since gait analysis proved able to reliably quantify CMT locomotor deficits, we aimed to explore whether it can be a sensitive-to-change outcome measure in CMT studies. Clinical and biomechanical evaluations were performed in 71 CMT subjects at baseline and after a mean (±sd) of 28.9 ± 9.5 months. Locomotor tasks included natural walking, ascending and descending steps. Instrumented analysis of such tasks provided indexes related to muscle strength (kinetic parameters) and joint movement (kinematic parameters). Parameter responsiveness was expressed as Standardized Response Mean (SRM). Considering the whole CMT group, several parameters showed moderate responsiveness; subgrouping subjects according to disease severity allowed reaching high responsiveness (SRM >0.80). CMT Examination Score showed moderate responsiveness (SRM 0.53) in the minimally affected group; kinematic parameters were more responsive in this group, whereas kinetic parameters in the most severely affected one. Biomechanical parameters can represent suitable outcome measures for CMT by showing moderate-to-high responsiveness. These data suggest that appropriate selection of patient population and outcome measures is crucial for clinical trials' design.