Elizabeth Luebbe

High-dosage ascorbic acid treatment in charcot-marie-tooth disease type 1A results of a randomized, double-masked, controlled trial

IMPORTANCE No current medications improve neuropathy in subjects with Charcot-Marie-Tooth disease type 1A (CMT1A). Ascorbic acid (AA) treatment improved the neuropathy of a transgenic mouse model of CMT1A and is a potential therapy. A lower dosage (1.5 g/d) did not cause improvement in humans. It is unknown whether a higher dosage would prove more effective. OBJECTIVE To determine whether 4-g/d AA improves the neuropathy of subjects with CMT1A. DESIGN A futility design to determine whether AA was unable to reduce worsening on the CMT Neuropathy Score (CMTNS) by at least 50% over a 2-year period relative to a natural history control group. SETTING Three referral centers with peripheral nerve clinics (Wayne State University, Johns Hopkins University, and University of Rochester). PARTICIPANTS One hundred seventy-four subjects with CMT1A were assessed for eligibility; 48 did not meet eligibility criteria and 16 declined to participate. The remaining 110 subjects, aged 13 to 70 years, were randomly assigned in a double-masked fashion with 4:1 allocation to oral AA (87 subjects) or matching placebo (23 subjects). Sixty-nine subjects from the treatment group and 16 from the placebo group completed the study. Two subjects from the treatment group and 1 from the placebo group withdrew because of adverse effects. INTERVENTIONS Oral AA (4 g/d) or matching placebo. MAIN OUTCOMES AND MEASURES Change from baseline to year 2 in the CMTNS, a validated composite impairment score for CMT. RESULTS The mean 2-year change in the CMTNS was -0.21 for the AA group and -0.92 for the placebo group, both better than natural history (+1.33). This was well below 50% reduction of CMTNS worsening from natural history, so futility could not be declared (P > .99). CONCLUSIONS AND RELEVANCE Both treated patients and those receiving placebo performed better than natural history. It seems unlikely that our results support undertaking a larger trial of 4-g/d AA treatment in subjects with CMT1A. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00484510.

If you build a rare disease registry, will they enroll and will they use it? Methods and data from the National Registry of Myotonic Dystrophy (DM) and Facioscapulohumeral Muscular Dystrophy (FSHD)

INTRODUCTION Registries are becoming increasingly important for rare diseases as experimental therapies develop. This report describes the methodology behind the National Registry of Myotonic Dystrophy (DM) and Facioscapulohumeral Muscular Dystrophy (FSHD) Patients and Family Members to facilitate the development of other rare disease registries. We also highlight data about the pathophysiology and select burdens of DM and FSHD reported at baseline and longitudinally. METHODS The Registry consists of de-identified, patient reported information collected at baseline and annually and information from review of medical records. Investigators can use the Registry to analyze de-identified data and to facilitate recruitment into clinical studies. RESULTS To date, the Registry has enrolled 1611 members, facilitated 24 studies, and collected data annually for up to 8 years. Genetic test results were obtained in 56.2% of enrollees. Approximately one-third of members used assistive devices and another one-third reported psychological problems at baseline. Wheelchair use was reported for both short and long distances by 7.0% of DM and 18.1% of FSHD members. Approximately 60% of members reported their employment was affected by their disease. CONCLUSIONS Strengths of the Registry include large sample sizes, stringent review of clinical and molecular data, annually updated information, and regular interactions between patients and investigators. Registry data provide new insights into the burdens of DM and FSHD, such as, psychological problems and reduced employment. Opportunities abound for investigators to utilize Registry resources to assess the impact of these and other burdens on health care costs, progression of symptoms, and quality of life.

Myotonic Dystrophy Health Index: initial evaluation of a disease-specific outcome measure.

Introduction: In preparation for clinical trials we examine the validity, reliability, and patient understanding of the Myotonic Dystrophy Health Index (MDHI). Methods: Initially we partnered with 278 myotonic dystrophy type‐1 (DM1) patients and identified the most relevant questions for the MDHI. Next, we used factor analysis, patient interviews, and test–retest reliability assessments to refine and evaluate the instrument. Lastly, we determined the capability of the MDHI to differentiate between known groups of DM1 participants. Results: Questions in the final MDHI represent 17 areas of DM1 health. The internal consistency was acceptable in all subscales. The MDHI had a high test–retest reliability (ICC = 0.95) and differentiated between DM1 patient groups with different disease severities. Conclusions: Initial evaluation of the MDHI provides evidence that it is valid and reliable as an outcome measure for assessing patient‐reported health. These results suggest that important aspects of DM1 health may be measured effectively using the MDHI. Muscle Nerve 49: 906–914, 2014

Myotonic dystrophy health index: Correlations with clinical tests and patient function

Introduction: The Myotonic Dystrophy Health Index (MDHI) is a disease‐specific patient‐reported outcome measure. Here, we examine the associations between the MDHI and other measures of disease burden in a cohort of individuals with myotonic dystrophy type‐1 (DM1). Methods: We conducted a cross‐sectional study of 70 patients with DM1. We examined the associations between MDHI total and subscale scores and scores from other clinical tests. Participants completed assessments of strength, myotonia, motor and respiratory function, ambulation, and body composition. Participants also provided blood samples, underwent physician evaluations, and completed other patient‐reported outcome measures. Results: MDHI total and subscale scores were strongly associated with muscle strength, myotonia, motor function, and other clinical measures. Conclusions: Patient‐reported health status, as measured by the MDHI, is associated with alternative measures of clinical health. These results support the use of the MDHI as a valid tool to measure disease burden in DM1 patients. Muscle Nerve, 2015 Muscle Nerve 53: 183–190, 2016

Parent-reported multi-national study of the impact of congenital and childhood onset myotonic dystrophy

The frequency and impact of symptoms experienced by patients with congenital, childhood, and juvenile‐onset myotonic dystrophy (CDM/ChDM/JDM) is not documented. This report identifies symptomatic areas with the greatest disease burden in an international population of patients with early‐onset myotonic dystrophy type‐1 (DM1).

The Impact of Congenital and Childhood Myotonic Dystrophy on Quality of Life A Qualitative Study of Associated Symptoms

This study systematically evaluated the symptoms associated with congenital and childhood myotonic dystrophy, and how these symptoms affect health related quality of life. We conducted interviews with patients affected by congenital or childhood myotonic dystrophy and their affected parent to identify which symptoms have the greatest effect on their lives. Each interview was recorded, coded, and analyzed using a qualitative framework technique. In 34 interviews with 13 parents and 21 patients, we identified 189 symptoms, representing 22 themes in physical, emotional, social, and disease-specific quality of life. Communication difficulties, cognitive impairment, and social role limitations were the most frequently identified themes. These interviews identified multiple themes and symptoms, some previously under-recognized, which play a key role in the disease burden associated with congenital and childhood myotonic dystrophy.

High Frequency of Gastrointestinal Manifestations in Myotonic Dystrophy Type 1 and Type 2

Objective: To analyze gastrointestinal (GI) manifestations, their progression over time, and medications being used to treat GI symptoms in a large cohort of patients with myotonic dystrophy types 1 (DM1) and 2 (DM2). Methods: We analyzed patient-reported data and medical records in a national registry cohort at baseline and 5 years. Results: At baseline, the majority of patients reported trouble swallowing in DM1 (55%; n = 499 of 913) and constipation in DM2 (53%; n = 96 of 180). Cholecystectomy occurred in 16.5% of patients with DM1 and 12.8% of patients with DM2, on average before 45 years of age. The use of medications indicated for gastroesophageal reflux disease was reported by 22.5% of DM1 and 18.9% of patients with DM2. Greater risk of a GI manifestation was associated with higher body mass index and longer disease duration in DM1 and female sex in DM2. At the 5-year follow-up, the most common new manifestations were trouble swallowing in patients with DM1 and constipation in patients with DM2. Conclusions: GI manifestations were common in both DM1 and DM2, with a relatively high frequency of gallbladder removal in DM1 and DM2 occurring at a younger age compared to normative data in the literature. Studies are needed to determine the pathomechanism of how sex, weight gain, and duration of disease contribute to GI manifestations and how these manifestations affect quality of life and clinical care for patients with DM1 and DM2.

Eight years after an international workshop on myotonic dystrophy patient registries: case study of a global collaboration for a rare disease

BackgroundMyotonic Dystrophy is the most common form of muscular dystrophy in adults, affecting an estimated 10 per 100,000 people. It is a multisystemic disorder affecting multiple generations with increasing severity. There are currently no licenced therapies to reverse, slow down or cure its symptoms. In 2009 TREAT-NMD (a global alliance with the mission of improving trial readiness for neuromuscular diseases) and the Marigold Foundation held a workshop of key opinion leaders to agree a minimal dataset for patient registries in myotonic dystrophy. Eight years after this workshop, we surveyed 22 registries collecting information on myotonic dystrophy patients to assess the proliferation and utility the dataset agreed in 2009. These registries represent over 10,000 myotonic dystrophy patients worldwide (Europe, North America, Asia and Oceania).ResultsThe registries use a variety of data collection methods (e.g. online patient surveys or clinician led) and have a variety of budgets (from being run by volunteers to annual budgets over €200,000). All registries collect at least some of the originally agreed data items, and a number of additional items have been suggested in particular items on cognitive impact.ConclusionsThe community should consider how to maximise this collective resource in future therapeutic programmes.

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.

Myotonic dystrophy patient preferences in patient-reported outcome measures: DM1 PRO Preferences

Introduction: When preparing for clinical trials in myotonic dystrophy type‐1 (DM1), it is important that researchers develop and identify patient‐reported outcome measures with good measurement properties. Methods: Fifty‐two DM1 patients enrolled in 2 clinical studies completed the Myotonic Dystrophy Health Index (MDHI), 36‐Item Short Form Health Survey (version 2; SF‐36v2), Individualized Neuromuscular Quality of Life questionnaire (INQoL), and a questionnaire comparing the relevance, usability, overall preference, and perceived responsiveness of each measure. The associations between instrument scores and physical function, genetic test results, and employment status were examined. Results: The MDHI was preferred over the INQoL in 13 of 13 areas and was preferred over the SF‐36v2 in 9 of 13 areas. The MDHI was the only score that was associated with participant employment status, CTG repeat length, and the 3 measurements of clinical function. Discussion: The MDHI correlates well with physical function and is viewed favorably by participants in DM1 clinical studies. Muscle Nerve 58: 49–55, 2018