Meaningful changes in motor function in Duchenne muscular dystrophy (DMD): A multi-center study.

Evaluations of treatment efficacy in Duchenne muscular dystrophy (DMD), a rare genetic disease that results in progressive muscle wasting, require an understanding of the 'meaningfulness' of changes in functional measures. We estimated the minimal detectable change (MDC) for selected motor function measures in ambulatory DMD, i.e., the minimal degree of measured change needed to be confident that true underlying change has occurred rather than transient variation or measurement error. MDC estimates were compared across multiple data sources, representing >1000 DMD patients in clinical trials and real-world clinical practice settings. Included patients were ambulatory, aged ≥4 to <18 years and receiving steroids. Minimal clinically important differences (MCIDs) for worsening were also estimated. Estimated MDC thresholds for >80% confidence in true change were 2.8 units for the North Star Ambulatory Assessment (NSAA) total score, 1.3 seconds for the 4-stair climb (4SC) completion time, 0.36 stairs/second for 4SC velocity and 36.3 meters for the 6-minute walk distance (6MWD). MDC estimates were similar across clinical trial and real-world data sources, and tended to be slightly larger than MCIDs for these measures. The identified thresholds can be used to inform endpoint definitions, or as benchmarks for monitoring individual changes in motor function in ambulatory DMD.

Efficacy and Safety of Vamorolone Over 48 Weeks in Boys With Duchenne Muscular Dystrophy: A Randomized Controlled Trial.

BACKGROUND AND OBJECTIVES: Vamorolone is a dissociative agonist of the glucocorticoid receptor that has shown similar efficacy and reduced safety concerns in comparison with prednisone in Duchenne muscular dystrophy (DMD). This study was conducted to determine the efficacy and safety of vamorolone over 48 weeks and to study crossover participants (prednisone to vamorolone; placebo to vamorolone). METHODS: A randomized, double-blind, placebo-controlled and prednisone-controlled clinical trial of 2 doses of vamorolone was conducted in participants with DMD, in the ages from 4 years to younger than 7 years at baseline. The interventions were 2 mg/kg/d of vamorolone and 6 mg/kg/d of vamorolone for 48 weeks (period 1: 24 weeks + period 2: 24 weeks) and 0.75 mg/kg/d of prednisone and placebo for the first 24 weeks (before crossover). Efficacy was evaluated through gross motor outcomes and safety through adverse events, growth velocity, body mass index (BMI), and bone turnover biomarkers. This analysis focused on period 2. RESULTS: A total of 121 participants with DMD were randomized. Vamorolone at a dose of 6 mg/kg/d showed maintenance of improvement for all motor outcomes to week 48 (e.g., for primary outcome, time to stand from supine [TTSTAND] velocity, week 24 least squares mean [LSM] [SE] 0.052 [0.0130] rises/s vs week 48 LSM [SE] 0.0446 [0.0138]). After 48 weeks, vamorolone at a dose of 2 mg/kg/d showed similar improvements as 6 mg/kg/d for North Star Ambulatory Assessment (NSAA) (vamorolone 6 mg/kg/d-vamorolone 2 mg/kg/d LSM [SE] 0.49 [1.14]; 95% CI -1.80 to 2.78, p = 0.67), but less improvement for other motor outcomes. The placebo to vamorolone 6 mg/kg/d group showed rapid improvements after 20 weeks of treatment approaching benefit seen with 48-week 6 mg/kg/d of vamorolone treatment for TTSTAND, time to run/walk 10 m, and NSAA. There was significant improvement in linear growth after crossover in the prednisone to vamorolone 6 mg/kg/d group, and rapid reversal of prednisone-induced decline in bone turnover biomarkers in both crossover groups. There was an increase in BMI after 24 weeks of treatment that then stabilized for both vamorolone groups. DISCUSSION: Improvements of motor outcomes seen with 6 mg/kg/d of vamorolone at 24 weeks of treatment were maintained to 48 weeks of treatment. Vamorolone at a dose of 6 mg/kg/d showed better maintenance of effect compared with vamorolone at a dose of 2 mg/kg/d for most (3/5) motor outcomes. Bone morbidities of prednisone (stunting of growth and declines in serum bone biomarkers) were reversed when treatment transitioned to vamorolone. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov Identifier: NCT03439670. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for boys with DMD, the efficacy of vamorolone at a dose of 6 mg/kg/d was maintained over 48 weeks.

Longitudinal Course of Long Finger Flexor Shortening in Males with Duchenne Muscular Dystrophy: A Retrospective Review1.

BACKGROUND: Shortening of the long finger flexors (Flexor Digitorum Profundus, FDPs) in Duchenne Muscular Dystrophy (DMD) causes reduced hand function. Until now, longitudinal studies on the natural course of the shortening of the FDPs are lacking, which impedes recommendations on timing and evaluation of preventive measures. OBJECTIVE: To investigate the longitudinal course of the FDP length during different disease stages focusing on symmetry, timing, and decline of the FDP length. METHODS: A retrospective, longitudinal multicenter study was conducted in the Radboud university medical center and the Leiden university medical center. The FDP outcome was measured using goniometry and gross motor function was assessed using the Brooke score. Longitudinal mixed model analyses were used to describe the course of the FDP outcome, and to investigate symmetry in both hands. RESULTS: Data on 534 visits of 197 males (age ranged 4-48 years) showed that in the ambulatory stages the FDP outcome was within a normal range. The mean decline in FDP outcome is 3.5 degrees per year, the biggest decline was seen in Brooke 5 (>15 degrees per year). In Brooke 4, 41% of the FDP outcome was < 40 degrees. No significant differences were found between right and left. CONCLUSIONS: This study supports the consideration of preventive measures to delay shortening of the FDPs in DMD patients transitioning to a Brooke scale of 4 or higher. Besides, natural history of FDP outcome has been established, which provides a base to evaluate (preventive) interventions.

Using PRPP-Assessment for measuring change in everyday activities by home-based videos: An exploratory case series study in children with multiple disabilities.

BACKGROUND: Currently, paediatric health care aims to use a child-centred tailor-made approach. In order to design tailored occupational therapy, the implementation of personalised occupation-based measurements that guide and evaluate goal setting and are responsive to change is necessary. PURPOSE: Primarily, this study explored the potential of the Perceive, Recall, Plan, and Perform (PRPP) assessment to measure the change in the performance of children with multiple disabilities. As a secondary evaluation, the feasibility of the PRPP-Intervention in a home-based program to enable activities was described. The overall aim is to show the potential of the PRPP-Assessment as an outcome measure to use as a base for designing tailor-made person-centred care. METHODS: An exploratory longitudinal multiple case series mixed-methods design was used. The PRPP-Assessment, scored by multiple raters, was conducted based on parent-provided videos. The assessed activities were chosen by the child and/or parents. Responsiveness was evaluated by hypotheses formulated a priori and by comparing measured change with change on concurrent measures: Goal Attainment Scaling (GAS) and Canadian Occupational Performance Measure (COPM). Over a 6-week period, children and their parents (or caregivers) participated in an online home-based video coaching program where parents were coached in the implementation of the training, based on the PRPP-Intervention, by paediatric occupational therapists on a weekly basis. The feasibility of the intervention was explored using semi-structured interviews with children, parents, and the treating occupational therapists and was analysed by directed content analysis. RESULTS: Three out of 17 eligible children agreed to participate and completed post-intervention measurement, of which two completed the intervention. Quantitative results showed that eight out of nine activities improved on the PRPP-Assessment and the COPM, and nine improved on the GAS. In total, 13 out of 15 hypotheses for responsiveness were accepted. Participants experienced the intervention as successful and acceptable. Facilitators and concerns over demand, implementation, practicality, integration, and adaptation were shared. CONCLUSION: The PRPP-Assessment showed the potential to measure change in a heterogeneous group of children. The results indicated a positive tendency for the intervention and also provide directions for further development.

Ready for handwriting? A reference data study on handwriting readiness assessments.

INTRODUCTION: Early evaluation of writing readiness is essential to predict and prevent handwriting difficulties and its negative influences on school occupations. An occupation-based measurement for kindergarten children has been previously developed: Writing Readiness Inventory Tool In Context (WRITIC). In addition, to assess fine motor coordination two tests are frequently used in children with handwriting difficulties: the modified Timed Test of In-Hand Manipulation (Timed TIHM) and the Nine-Hole Peg Test (9-HPT). However, no Dutch reference data are available. AIM: To provide reference data for (1) WRITIC, (2) Timed-TIHM and (3) 9-HPT for handwriting readiness assessment in kindergarten children. METHODS: Three hundred and seventy-four children from Dutch kindergartens in the age of 5 to 6.5 years (5.6±0.4 years, 190 boys/184 girls) participated in the study. Children were recruited at Dutch kindergartens. Full classes of the last year were tested, children were excluded if there was a medical diagnosis such as a visual, auditory, motor or intellectual impairment that hinder handwriting performance. Descriptive statistics and percentiles scores were calculated. The score of the WRITIC (possible score 0-48 points) and the performance time on the Timed-TIHM and 9-HPT are classified as percentile scores lower than the 15th percentile to distinguish low performance from adequate performance. The percentile scores can be used to identify children that are possibly at risk developing handwriting difficulties in first grade. RESULTS: WRITIC scores ranged from 23 to 48 (41±4.4), Timed-TIHM ranged from 17.9 to 64.5 seconds (31.4± 7.4 seconds) and 9-HPT ranged from 18.2 to 48.3 seconds (28.4± 5.4). A WRITIC score between 0-36, a performance time of more than 39.6 seconds on the Timed-TIHM and more than 33.8 seconds on the 9-HPT were classified as low performance. CONCLUSION: The reference data of the WRITIC allow to assess which children are possibly at risk developing handwriting difficulties.

DMD Genotypes and Motor Function in Duchenne Muscular Dystrophy: A Multi-institution Meta-analysis With Implications for Clinical Trials.

BACKGROUND AND OBJECTIVES: Clinical trials of genotype-targeted treatments in Duchenne muscular dystrophy (DMD) traditionally compare treated patients with untreated patients with the same DMD genotype class. This avoids confounding of drug efficacy by genotype effects but also shrinks the pool of eligible controls, increasing challenges for trial enrollment in this already rare disease. To evaluate the suitability of genotypically unmatched controls in DMD, we quantified effects of genotype class on 1-year changes in motor function endpoints used in clinical trials. METHODS: More than 1,600 patient-years of follow-up (>700 patients) were studied from 6 real-world/natural history data sources (UZ Leuven, PRO-DMD-01 shared by CureDuchenne, iMDEX, North Star UK, Cincinnati Children's Hospital Medical Center, and the DMD Italian Group), with genotypes classified as amenable to skipping exons 44, 45, 51, or 53, or other skippable, nonsense, and other mutations. Associations between genotype class and 1-year changes in North Star Ambulatory Assessment total score (ΔNSAA) and in 10-m walk/run velocity (Δ10MWR) were studied in each data source with and without adjustment for baseline prognostic factors. RESULTS: The studied genotype classes accounted for approximately 2% of variation in ΔNSAA outcomes after 12 months, whereas other prognostic factors explained >30% of variation in large data sources. Based on a meta-analysis across all data sources, pooled effect estimates for the studied skip-amenable mutation classes were all small in magnitude (<2 units in ΔNSAA total score in 1-year follow up), smaller than clinically important differences in NSAA, and were precisely estimated with standard errors <1 unit after adjusting for nongenotypic prognostic factors. DISCUSSION: These findings suggest the viability of trial designs incorporating genotypically mixed or unmatched controls for up to 12 months in duration for motor function outcomes, which would ease recruitment challenges and reduce numbers of patients assigned to placebos. Such trial designs, including multigenotype platform trials and hybrid designs, should ensure baseline balance between treatment and control groups for the most important prognostic factors, while accounting for small remaining genotype effects quantified in this study.

Long-term outcomes for females with early-onset dystrophinopathy.

AIM: To study long-term disease course for females with early-onset dystrophinopathy, including common (female) symptoms, challenges in social participation, the need for care, and current healthcare management to support guideline development. METHOD: Twelve females with early-onset dystrophinopathy were followed for a median period of more than 17 years (range 1-36). RESULTS: One patient died owing to end-stage cardiac failure. Cardiac abnormalities were observed in three of the remaining 11 participants. Respiratory function was reduced in seven of 10 participants. Fatigue, myalgia, lower back pain, and arthralgia were reported in more than six of the participants. Functional status varied from exercise intolerance to wheelchair dependency. Most or all of the 10 participants reported restrictions in participation in work (n = 10), household duties (n = 10), sports (n = 9), and education (n = 8). Only a few participants received followed-up pulmonary (n = 2) or rehabilitation (n = 3) care. INTERPRETATION: Females with early-onset dystrophinopathy experience a wide range of impairments, comorbidities, limitations in activities, and restrictions in social participation. The whole spectrum should be acknowledged in the healthcare setting. Neuromuscular and cardiac follow-up are indispensable. Additional respiratory assessment and rehabilitation care are expected to improve health status and support daily activities and participation. WHAT THIS PAPER ADDS: No standard diagnostic procedures seem to exist for female patients suspected for dystrophinopathy. Female participants with early-onset dystrophinopathy experienced a broad scope of burdening symptoms, such as fatigue, myalgia, lower back pain, and arthralgia. None of participants worked full time, all felt restricted in paid work, and most felt restricted in education. Most participants showed decreased lung function, while only one was symptomatic. Availability of rehabilitation care may improve support for daily activities and participation for females with early-onset dystrophinopathy.

The reliability and validity of the perceive, recall, plan and perform assessment in children with a mitochondrial disorder.

PURPOSE: To investigate the reliability and validity of the Perceive, Recall, Plan and Perform System of Task Analysis (PRPP-Assessment) by parent-provided videos of children with mitochondrial disorders. METHODS: Videos of 13 children performing 3-7 activities each were the subject of study, resulting in 65 activities. These were scored using the PRPP-Assessment by 11 raters. Internal consistency was calculated with Cronbach's alpha. Intra-rater reliability was evaluated by Bland-Altman Plots on 44 PRPP-Assessment scores. Inter-rater reliability was calculated with ICCAgreement on 128 PRPP-Assessment scores. Construct validity was assessed by comparing the PRPP-Assessment scores to the Canadian Occupational Performance Measure using Cohen's Kappa. PRPP-Assessments scores were evaluated with a multi-faceted Rasch Analysis. RESULTS: Internal consistency was high (0.92). Intra-rater reliability was sufficient to be good (92-96% within the 95%-Limits of the Agreement). The ICCAgreement for stage 1 Mastery Score showed acceptable inter-rater reliability (0.646). Stage 2 of the PRPP-Assessment showed low ICCs due to a lack of variability within the sample. Four out of six hypotheses on validity were accepted. Rasch's analysis demonstrated sound goodness-of-fit, and supported the validity of the PRPP-Assessment. CONCLUSION: The PRPP-Assessment by parent-provided videos in this heterogenic group showed sufficient to good psychometric properties. In practice, careful task selection and formulating criterion is recommended.Implications for RehabilitationPRPP-Assessment by parent-provided videos is reliable and valid in the complex, heterogenous group of children with mitochondrial disordersThe PRPP-Assessment is suitable for children with mitochondrial disorders as it showed to contain familiar, functional and meaningful tasks and activities that fit with their level of functioningProfessionals should be aware that parents might not be used to the criterium-based frame of reference of the PRPP-AssessmentWhen applying the PRPP-Assessment, it is recommended to be careful in task selection and formulating the criterion.

Efficacy and Safety of Vamorolone vs Placebo and Prednisone Among Boys With Duchenne Muscular Dystrophy: A Randomized Clinical Trial.

Importance: Corticosteroidal anti-inflammatory drugs are widely prescribed but long-term use shows adverse effects that detract from patient quality of life. Objective: To determine if vamorolone, a structurally unique dissociative steroidal anti-inflammatory drug, is able to retain efficacy while reducing safety concerns with use in Duchenne muscular dystrophy (DMD). Design, Setting, and Participants: Randomized, double-blind, placebo- and prednisone-controlled 24-week clinical trial, conducted from June 29, 2018, to February 24, 2021, with 24 weeks of follow-up. This was a multicenter study (33 referral centers in 11 countries) and included boys 4 to younger than 7 years of age with genetically confirmed DMD not previously treated with corticosteroids. Interventions: The study included 4 groups: placebo; prednisone, 0.75 mg/kg per day; vamorolone, 2 mg/kg per day; and vamorolone, 6 mg/kg per day. Main Outcomes and Measures: Study outcomes monitored (1) efficacy, which included motor outcomes (primary: time to stand from supine velocity in the vamorolone, 6 mg/kg per day, group vs placebo; secondary: time to stand from supine velocity [vamorolone, 2 mg/kg per day], 6-minute walk distance, time to run/walk 10 m [vamorolone, 2 and 6 mg/kg per day]; exploratory: NorthStar Ambulatory Assessment, time to climb 4 stairs) and (2) safety, which included growth, bone biomarkers, and a corticotropin (ACTH)-challenge test. Results: Among the 133 boys with DMD enrolled in the study (mean [SD] age, 5.4 [0.9] years), 121 were randomly assigned to treatment groups, and 114 completed the 24-week treatment period. The trial met the primary end point for change from baseline to week 24 time to stand velocity for vamorolone, 6 mg/kg per day (least-squares mean [SE] velocity, 0.05 [0.01] m/s vs placebo -0.01 [0.01] m/s; 95% CI, 0.02-0.10; P = .002) and the first 4 sequential secondary end points: time to stand velocity, vamorolone, 2 mg/kg per day, vs placebo; 6-minute walk test, vamorolone, 6 mg/kg per day, vs placebo; 6-minute walk test, vamorolone, 2 mg/kg per day, vs placebo; and time to run/walk 10 m velocity, vamorolone, 6 mg/kg per day, vs placebo. Height percentile declined in prednisone-treated (not vamorolone-treated) participants (change from baseline [SD]: prednisone, -1.88 [8.81] percentile vs vamorolone, 6 mg/kg per day, +3.86 [6.16] percentile; P = .02). Bone turnover markers declined with prednisone but not with vamorolone. Boys with DMD at baseline showed low ACTH-stimulated cortisol and high incidence of adrenal insufficiency. All 3 treatment groups led to increased adrenal insufficiency. Conclusions and Relevance: In this pivotal randomized clinical trial, vamorolone was shown to be effective and safe in the treatment of boys with DMD over a 24-week treatment period. Vamorolone may be a safer alternative than prednisone in this disease, in which long-term corticosteroid use is the standard of care. Trial Registration: ClinicalTrials.gov Identifier: NCT03439670.

Orthopedic Interventions for Foot Deformities in Non-Ambulant People with Duchenne Muscular Dystrophy: A Retrospective Study on Indications, Post-Operative and Long-Term Outcomes.

BACKGROUND: Progressive equinovarus deformities are common in people with Duchenne Muscular Dystrophy (DMD); they may provoke pain, pressure spots, cause problems with wearing footwear, and may lead to an unstable sitting position. OBJECTIVE: Explore indications and compare complications and long-term outcomes after soft tissue and osseous interventions in people with DMD. METHODS: Retrospective, monocenter, longitudinal study. Data on indications, equinus and varus deformity before and after surgery, wound healing problems, 'pain', edema, and long-term outcomes were collected from medical files. Soft tissue interventions were compared with osseous interventions. RESULTS: From a series of 18 patients, data on 32 surgical interventions and 169 follow-up visits were analyzed. 'Footrest placement' was the most frequent surgical indication, followed by pain. Osseous interventions were performed in older patients with rigid deformities. Directly after surgery remaining deformities were reported after soft tissue interventions (18 %), no remaining deformities were reported after osseous interventions. Pain and edema were frequently present, especially after osseous surgery. Longitudinal follow-up showed that surgical interventions could lead to a neutral foot for a for more than 3 years on average years. Relapses of foot deformity occurred, especially the recurrence of varus deformity after osseous interventions. CONCLUSIONS: Surgical interventions can successfully lead to a neutral foot position for for more than 3 years on average. Soft tissue interventions appear to be superior to osseous corrections, considering the varus recurrence period and complications, and may be considered when feet are still (partly) correctable. Pain management and edema prevention should be anticipated before surgery. Future research on patient reported outcomes as well as evaluating the outcome of the initial indication is needed to further identify benefits.

The Black Box of Technological Outcome Measures: An Example in Duchenne Muscular Dystrophy.

BACKGROUND: Outcome measures for non-ambulant Duchenne muscular dystrophy (DMD) patients are limited, with only the Performance of the Upper Limb (PUL) approved as endpoint for clinical trials. OBJECTIVE: We assessed four outcome measures based on devices developed for the gaming industry, aiming to overcome disadvantages of observer-dependency and motivation. METHODS: Twenty-two non-ambulant DMD patients (range 8.6-24.1 years) and 14 healthy controls (HC; range 9.5-25.4 years) were studied at baseline and 16 patients at 12 months using Leap Motion to quantify wrist/hand active range of motion (aROM) and a Kinect sensor for reached volume with Ability Captured Through Interactive Video Evaluation (ACTIVE), Functional Workspace (FWS) summed distance to seven upper extremity body points, and trunk compensation (KinectTC). PUL 2.0 was performed in patients only. A stepwise approach assessed quality control, construct validity, reliability, concurrent validity, longitudinal change and patient perception. RESULTS: Leap Motion aROM distinguished patients and HCs for supination, radial deviation and wrist flexion (range p = 0.006 to <0.001). Reliability was low and the manufacturer's hand model did not match the sensor's depth images. ACTIVE differed between patients and HCs (p < 0.001), correlated with PUL (rho = 0.76), and decreased over time (p = 0.030) with a standardized response mean (SRM) of -0.61. It was appraised as fun on a 10-point numeric rating scale (median 9/10). PUL decreased over time (p < 0.001) with an SRM of -1.28, and was appraised as fun (median 7/10). FWS summed distance distinguished patients and HCs (p < 0.001), but reliability in patients was insufficient. KinectTC differed between patients and HCs (p < 0.01), but correlated insufficiently with PUL (rho = -0.69). CONCLUSIONS: Only ACTIVE qualified as potential outcome measure in non-ambulant DMD patients, although the SRM was below the commonly used threshold of 0.8. Lack of insight in technological constraints due to intellectual property and software updates made the technology behind these outcome measures a kind of black box that could jeopardize long-term use in clinical development.

Martial Arts Training for Boys With Duchenne Muscular Dystrophy.

PURPOSE: The primary aim of this pilot study was to investigate the safety and feasibility of a 3-month martial arts-based training (MAT) program for patients with Duchenne muscular dystrophy (DMD). The secondary aim was to examine changes in physical and psychosocial abilities after participating in the MAT program. METHODS: Twelve patients with DMD (10 ambulant and 2 nonambulant) were included. The MAT program was evaluated on feasibility and safety. Changes in physical abilities were measured using the Motor Function Measure, Performance of Upper Limb scale, and the North Star Ambulatory Assessment. Changes in psychosocial abilities were measured using the Strength and Difficulties Questionnaire, Personal Adjustment and Role Skills for DMD, and the Self-Perception Profile for Children/Adolescents. RESULTS: Two participants did not complete the MAT program. Attendance rate for the 10 remaining participants was 91%. Eleven falls were reported during the training, but these falls did not result in injuries. Therefore, the MAT program was found feasible and safe. After completing the MAT program, most participants showed an improvement of their psychosocial abilities, and their physical abilities did not show deterioration. CONCLUSION: The MAT program is feasible and safe for boys with DMD.

BMI-z scores of boys with Duchenne muscular dystrophy already begin to increase before losing ambulation: a longitudinal exploration of BMI, corticosteroids and caloric intake.

We aimed to investigate BMI-z course in patients with Duchenne muscular dystrophy (DMD) during transition to loss of ambulation, and to explore the contribution of caloric intake and corticosteroid use. A retrospective multicenter longitudinal study was conducted. First, analyses of characteristics at first visit were carried out. Second, discontinuous change models were fitted to explore associations between BMI-z, loss of ambulation, caloric intake and corticosteroid use. 790 visits of 159 patients were collected. Cross sectional first visit analyses showed the presence of overweight and obesity was 44% in the ambulant group and 51% in the non-ambulant group. In the non-ambulatory group, exceeding the recommended caloric intake was associated with higher BMI-z scores (r 0.36, p = 0.04). Patients who were using corticosteroids had significantly higher BMI-z scores compared with patients not using corticosteroids (1.06 and 0.51 respectively, p = 0.02). Longitudinal analyses on patients ambulant at first visit showed an increase in BMI-z score during transition to the non-ambulatory phase. Caloric intake and corticosteroid use were not associated with BMI-z. Transition to the non-ambulatory phase may be crucial in the development of excessive weight gain. Early measures - starting before this time frame - may contribute to reduce development of obesity.

Natural History of Facioscapulohumeral Dystrophy in Children: A 2-Year Follow-up.

BACKGROUND AND OBJECTIVES: Data on the natural history of facioscapulohumeral dystrophy (FSHD) in childhood are limited and critical for improved patient care and clinical trial readiness. Our objective was to describe the disease course of FSHD in children. METHODS: We performed a nationwide, single-center, prospective cohort study of FSHD in childhood assessing muscle functioning, imaging, and quality of life over 2 years of follow-up. RESULTS: We included 20 children with genetically confirmed FSHD who were 2 to 17 years of age. Overall, symptoms were slowly progressive, and the mean FSHD clinical score increased from 2.1 to 2.8 (p = 0.003). The rate of progression was highly variable. At baseline, 16 of 20 symptomatic children had facial weakness; after 2 years, facial weakness was observed in 19 of 20 children. Muscle strength did not change between baseline and follow-up. The most frequently and most severely affected muscles were the trapezius and deltoid. The functional exercise capacity, measured with the 6-minute walk test, improved. Systemic features were infrequent and nonprogressive. Weakness-associated complications such as lumbar hyperlordosis and dysarthria were common, and their prevalence increased during follow-up. Pain and fatigue were frequent complaints in children, and their prevalence also increased during follow-up. Muscle ultrasonography revealed a progressive increase in echogenicity. DISCUSSION: FSHD in childhood has a slowly progressive but variable course over 2 years of follow-up. The most promising outcome measures to detect progression were the FSHD clinical score and muscle ultrasonography. Despite this disease progression, an improvement on functional capacity may still occur as the child grows up. Pain, fatigue, and a decreased quality of life were common symptoms and need to be addressed in the management of childhood FSHD. Our data can be used to counsel patients and as baseline measures for treatment trials in childhood FSHD.

Association of Elbow Flexor MRI Fat Fraction With Loss of Hand-to-Mouth Movement in Patients With Duchenne Muscular Dystrophy.

BACKGROUND AND OBJECTIVES: To study the potential of quantitative MRI (qMRI) fat fraction (FF) as a biomarker in nonambulant patients with Duchenne muscular dystrophy (DMD), we assessed the additive predictive value of elbow flexor FF to age at loss of hand-to-mouth movement. METHODS: Nonambulant patients with DMD (age ≥8 years) were included. Four-point Dixon MRI scans of the right upper arm were performed at baseline and at the 12-, 18-, or 24-month follow-up. Elbow flexor FFs were determined from 5 central slices. Loss of hand-to-mouth movement was determined at study visits and by phone calls every 4 months. FFs were fitted to a sigmoidal curve by use of a mixed model with random slope to predict individual trajectories. The added predictive value of elbow flexor FF to age at loss of hand-to-mouth movement was calculated from a Cox model with the predicted FF as a time-varying covariate, yielding a hazard ratio. RESULTS: Forty-eight MRIs of 20 patients with DMD were included. The hazard ratio of a percent-point increase in elbow flexor FF for the time to loss of hand-to-mouth movement was 1.12 (95% confidence interval 1.04-1.21; p = 0.002). This corresponded to a 3.13-fold increase in the instantaneous risk of loss of hand-to-mouth movement in patients with a 10-percent points higher elbow flexor FF at any age. DISCUSSION: In this prospective study, elbow flexor FF predicted loss of hand-to-mouth movement independently of age. qMRI-measured elbow flexor FF can be used as a surrogate endpoint or stratification tool for clinical trials in nonambulant patients with DMD. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that qMRI FF of elbow flexor muscles in patients with DMD predicts loss of hand-to-mouth movement independently of age.

Prevalence of Bladder and Bowel Dysfunction in Duchenne Muscular Dystrophy Using the Childhood Bladder and Bowel Dysfunction Questionnaire.

INTRODUCTION: Lower urinary tract symptoms (LUTS) and gastrointestinal (GI) problems are common in Duchenne muscular dystrophy (DMD), but not systematically assessed in regular care. We aimed to determine the prevalence of bladder and bowel dysfunction (BBD) in DMD patients compared with healthy controls (HC). METHODS: The Childhood Bladder and Bowel Dysfunction Questionnaire (CBBDQ) based on the International Rome III criteria and the International Children's Continence Society was filled out by 57 DMD patients and 56 HC. Additionally, possible associations of BBD with, for example, medication use or quality of life were evaluated in an additional questionnaire developed by experts. RESULTS: In 74% of patients versus 56% of HC ≥ 1 LUTS (n.s.) were reported, 68% of patients versus 39% of HC reported ≥1 bowel symptom (p = 0.002) and 53% of patients versus 30% of HC reported combined LUTS and bowel symptoms (p = 0.019). A negative impact of BBD on daily life functioning was reported by 42% of patients. CONCLUSIONS: These data underscore that standard screening for BBD is needed and that the CBBDQ could be of added value to optimize DMD care.

Occurrence of symptoms in different stages of Duchenne muscular dystrophy and their impact on social participation.

INTRODUCTION/AIMS: As life expectancy improves for patients with Duchenne muscular dystrophy (DMD), new symptoms are likely to arise. This aims of this study are: (1) to explore the prevalence of a broad variety of symptoms in the various stages of DMD (with and without steroid use); (2) to explore the prevalence of common secondary diagnoses; and (3) to evaluate the social participation level of patients with DMD older than 16 y of age; and to explore correlations between social participation and symptoms. METHODS: A cross-sectional self-report questionnaire, including questions on functional level and health status, as well as a standardized participation scale was distributed among Dutch patients with DMD. RESULTS: Eighty-four male patients with a mean age of 22.0 (SD = 10.0) y were enrolled. The most prevalent and limiting symptoms were difficulty coughing (58%), coldness of hands (57%), contractures (51%), stiffness (49%), fatigue (40%), myalgia (38%), and low speech volume (33%). Prevalent secondary diagnoses included cardiac disease (14%), neurobehavioral diagnosis (13%), low blood pressure (13%), and arthrosis (5%). Social participation correlated negatively with coldness of hands (r = - .29; P < .03), decreased intelligibility (r = - .40; P < .003), and chewing problems (r = - .33; P < .02). DISCUSSION: The prevalence of a broad spectrum of symptoms and secondary diagnoses is high in patients with DMD, and some of these symptoms are correlated with social participation. Growing awareness of new symptoms and secondary diagnoses among patients, caregivers, and professionals can enhance their recognition, possibly facilitating prevention and early treatment.

Compliance to DMD Care Considerations in the Netherlands.

BACKGROUND AND OBJECTIVE: To optimize care for patients with DMD, it is essential to know to what extent current care complies with the recommended monitoring frequencies suggested by the DMD care considerations. The objective of this study was to investigate the current care for patients with DMD in the Netherlands and to what extent the care complies with the international care considerations. METHODS: A cross-sectional questionnaire was carried out among the Dutch DMD patients and caregivers about the patients' functional and health status, visits to healthcare professionals, clinical tests and assessments, therapy, medication use and access to medical aids and devices. Compliance to guidelines was defined by comparing the frequency of visits to health care providers and clinical tests with the recommended frequencies derived from the care considerations of 2010. RESULTS: Eighty-four participants completed the questionnaire. The majority of participants met the recommended visit frequencies to a neuromuscular specialist and cardiologist. Compliance was suboptimal for respiratory assessments in the non-ambulatory phase, monitoring of side effects of corticosteroid use and neuromuscular assessments. Disease specific information supply was perceived as sufficient and participants were satisfied with the received care. CONCLUSIONS: This study identifies areas in which compliance is lacking. Countries, such as the Netherlands, working according to a shared care system require easy and low-threshold communication between health care centers and a clear division of roles and responsibilities to reach optimal compliance. In the Netherlands the Duchenne Center Netherlands has the coordinating role.

Feasibility and effectiveness of a novel dynamic arm support in persons with spinal muscular atrophy and duchenne muscular dystrophy.

BACKGROUND: Neuromuscular disorders (NMD) commonly affect the upper extremity. Due to muscle weakness, performance of daily activities becomes increasingly difficult, which leads to reduced independence and quality of life. In order to support the performance of upper extremity tasks, dynamic arm supports may be used. The Yumen Arm is a novel dynamic arm support specially developed for people with NMD. The aim of this study is to evaluate the feasibility and effectiveness of the Yumen Arm in persons with Duchenne Muscular Dystrophy (DMD) and persons with Spinal Muscular Atrophy (SMA). METHODS: Three persons with DMD and three persons with SMA participated in this study. All participants conducted a set of measures with and without the Yumen Arm. Outcome measures were: active range of motion of the arm and trunk (i.e. Reachable Workspace, Functional Workspace, and trunk movement), fatigue (OMNI-RPE), Performance of Upper Limb (PUL) scale and some additional activities of daily living. User experiences were collected using a questionnaire. RESULTS: The Yumen Arm could be used by all participants. Results showed a median increase in active range of motion (4% relative surface area), and a median increase of function ability (> 11% PUL score) when using the Yumen Arm. In addition, three out of four (data from 2 participants was missing) participants indicated that activity performance was less fatiguing when using the Yumen Arm. Four out of five (data from 1 participant was missing) participants indicated that they would like to use the Yumen Arm in their daily lives. CONCLUSION: This study is one of the first studies describing a range of objective measures to examine the effectiveness of a dynamic arm support. Based on these measurements we can conclude that the Yumen Arm effectively improves arm function in NMD patients, however the effectiveness varies a lot between individual subjects. We provided detailed recommendations for the improvement of the Yumen Arm, and possible also for the development of other dynamic arm supports. This study showed a lot of variability between individual subjects, which emphasizes the importance of tuning dynamic arm supports based on individual user characteristics, such as scoliosis, functional capacity and muscle strength.

Clinical Management of Duchenne Muscular Dystrophy in the Netherlands: Barriers to and Proposals for the Implementation of the International Clinical Practice Guidelines.

BACKGROUND: In order to successfully implement the international clinical care guidelines for Duchenne muscular dystrophy (DMD) in the Netherlands, it is essential to know what barriers are experienced by healthcare practitioners regarding guideline adherence and organization of care. In the Netherlands, academic medical centers provide follow up visits and work together with peripheral hospitals, rehabilitation centers, centers for home ventilation and primary care centers for treatment. OBJECTIVE: To investigate perceived barriers to international clinical DMD guideline adherence and identify potential areas of improvement for implementation in the Dutch 'shared care' organization. METHODS: Semi-structured in-depth interviews with healthcare practitioners of academic medical hospitals and questionnaires for healthcare practitioners of rehabilitation centers, based on the framework of Cabana. RESULTS: The analyses identified 4 barriers for non-adherence to the DMD guideline: (i) lack of familiarity/awareness, (ii) lack of agreement with specific guideline, (iii) lack of outcome expectancy, (iv) external barriers. CONCLUSIONS: A heterogeneous set of barriers is present. Therefore, a multifaceted intervention strategy is proposed to overcome these barriers, including a clear division of roles, allowing for local (Dutch) adaptations per specialism by local consensus groups, and the facilitation of easy communication with experts/opinion leaders as well as between care professionals.