Background:Telemedicine (TM) contributes to bridge the gap between healthcare facilities and patients’ homes with neuromuscular disease (NMD) because of mobility issues. However, its deployment is... Show moreBackground:Telemedicine (TM) contributes to bridge the gap between healthcare facilities and patients’ homes with neuromuscular disease (NMD) because of mobility issues. However, its deployment is limited due to difficulties evaluating subtle neurological signs such as mild weakness or sensory deficits. The COVID-19 pandemic has disrupted healthcare delivery worldwide, necessitating rapid measures implementation by health care providers (HCPs) to protect patients from acquiring SARS-CoV-2 while maintaining the best care and treatment.Objectives:Given the challenges faced by remote healthcare assistance of NMD patients, we aim to evaluate the use of TM in NMD during the COVID-19 pandemic.Methods:Based on the Model for Assessment-of-Telemedicine-Applications (MAST), we conducted a survey amongst clinicians of the ERN EURO NMD (European-Reference-Network-for-Rare-Neuromuscular-Diseases).Results:Based on 42 responses over 76 expected ones, our results show that the COVID-19 pandemic significantly increased the number of HCPs using TM (from 60% to 100%). The TM types most used during the COVID-19 period are teleconsultation and consultation by phone, particularly in the context of symptoms worsening in NMD patients with COVID-19 infection. Most European HCPs were satisfied when using TM but as a complementary option to physical consultations. Many responses addressed the issue of technical aspects needing improvement, particularly for elderly patients who need caregivers’ assistance for accessing the TM platform.Conclusions:TM has been essential during COVID-19, but its use still presents some limitations for NMD patients with cognitive deficits or for first-time diagnosis. Thus, TM should be used as complement to, rather than substitute, for face-to-face consultations. Show less
Introduction:MRI of extra-ocular muscles (EOM) in patients with myasthenia gravis (MG) could aid in diagnosis and provide insights in therapy-resistant ophthalmoplegia. We used quantitative MRI to... Show moreIntroduction:MRI of extra-ocular muscles (EOM) in patients with myasthenia gravis (MG) could aid in diagnosis and provide insights in therapy-resistant ophthalmoplegia. We used quantitative MRI to study the EOM in MG, healthy and disease controls, including Graves’ ophthalmopathy (GO), oculopharyngeal muscular dystrophy (OPMD) and chronic progressive external ophthalmoplegia (CPEO).Methods:Twenty recently diagnosed MG (59±19yrs), nineteen chronic MG (51±16yrs), fourteen seronegative MG (57±9yrs) and sixteen healthy controls (54±13yrs) were included. Six CPEO (49±14yrs), OPMD (62±10yrs) and GO patients (44±12yrs) served as disease controls. We quantified muscle fat fraction (FF), T2water and volume. Eye ductions and gaze deviations were assessed by synoptophore and Hess-charting.Results:Chronic, but not recent onset, MG patients showed volume increases (e.g. superior rectus and levator palpebrae [SR+LPS] 985±155 mm3 compared to 884±269 mm3 for healthy controls, p < 0.05). As expected, in CPEO volume was decreased (e.g. SR+LPS 602±193 mm3, p < 0.0001), and in GO volume was increased (e.g. SR+LPS 1419±457 mm3, p < 0.0001). FF was increased in chronic MG (e.g. medial rectus increased 0.017, p < 0.05). In CPEO and OPMD the FF was more severely increased. The severity of ophthalmoplegia did not correlate with EOM volume in MG, but did in CPEO and OPMD. No differences in T2water were found.Interpretation:We observed small increases in EOM volume and FF in chronic MG compared to healthy controls. Surprisingly, we found no atrophy in MG, even in patients with long-term ophthalmoplegia. This implies that even long-term ophthalmoplegia in MG does not lead to secondary structural myopathic changes precluding functional recovery. Show less
Background: In Becker muscular dystrophy evidence for neurocognitive and behavioral comorbidity is evolving. More insight into the extend of these problems is of great importance for early... Show moreBackground: In Becker muscular dystrophy evidence for neurocognitive and behavioral comorbidity is evolving. More insight into the extend of these problems is of great importance for early detection and remediation in clinical practice.Objective: In this study we aimed to describe the neurocognitive and behavioral features of a Dutch adult cohort of BMD patients, and to evaluate correlations to motor function outcomes.Methods: 28 adult BMD patients were included. Intelligence, executive functioning, verbal memory and reaction times were assessed cross-sectionally. Additionally, patients completed questionnaires on behavioral and emotional symptoms, psychosocial and executive functions. Results were compared to normative data and correlated with disease severity as measured by the 10-meter run/walk test and Performance of the Upper Limb version 1.2.Results: 15 patients (53.6%) had a high educational level despite frequent grade repeating (48.3%) during primary or secondary school. Neuropsychological testing revealed that intellectual abilities, verbal memory, processing speed and executive functioning were statistically significant below average, but still within normal range. Regarding outcomes of the behavioral questionnaires, no significant differences were reported compared to the norm population. No relevant correlations with disease severity were found.Conclusions: This cohort of adult BMD patients exhibits minor cognitive impairments and no significant behavioral problems. The lower outcomes on processing speed and verbal memory, combined with the relatively high prevalence of grade repeating during primary and secondary school, implies that these minor impairments played a role in childhood. However, the on average high educational levels suggests that they grow out of their cognitive impairments with ageing. Show less
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... Show moreBackground: 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 (rangep = 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. Show less
Heutinck, L.; Gameren, M. van; Verschuuren, J.J.G.M.; Geurts, A.C.H.; Jansen, M.; Groot, I.J.M. de 2021
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... Show moreBackground: 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. Show less
Lin, N. van; Paliouras, G.; Vroom, E.; Hoen, P.A.C. 't; Roos, M. 2021
Background: For patients with rare diseases such as Duchenne and Becker muscular dystrophy (DMD/BMD), access to their health data is key to being able to advocate for themselves and be in control... Show moreBackground: For patients with rare diseases such as Duchenne and Becker muscular dystrophy (DMD/BMD), access to their health data is key to being able to advocate for themselves and be in control of their care. Since 2018, the DMD/BMD patient community has been committed to making DMD/BMD-related data FAIR, i.e., Findable, Accessible, Interoperable, and Reusable. On March 3, 2021, the second international meeting on FAIR data sharing for DMD/BMD was held virtually.Objective: The aim of this meeting report is to summarize the presentations and discussions of the meeting.Methods: During this meeting, the progress of FAIRification efforts since the first international meeting in 2019, new developments, stakeholder perspectives, and experiences from implementing FAIR data principles in practice were presented and discussed.Results: Over 120 attendees representing various stakeholder groups (ie, patient organizations, clinicians, clinical and academic researchers, pharmaceutical companies, regulators, and EU organizations) from 22 countries participated in the meeting. This meeting report summarizes the presentations and discussions from the meeting, provides an overview of the key lessons learned since the first meeting, and outlines the next steps.Conclusions: Patient organizations are key drivers of the FAIRification process in practice and dialogue with stakeholders is critical to success. Show less
Heutinck, L.; Houwen-van Opstal, S.L.S.; Krom, Y.D.; Niks, E.H.; Verschuuren, J.J.G.M.; Jansen, M.; Groot, I.J.M. de 2021
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... Show moreBackground 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. Show less
Duchenne muscular dystrophy is an X-linked, recessive muscular dystrophy in which the absence of the dystrophin protein leads to fibrosis, inflammation and oxidative stress, resulting in loss of... Show moreDuchenne muscular dystrophy is an X-linked, recessive muscular dystrophy in which the absence of the dystrophin protein leads to fibrosis, inflammation and oxidative stress, resulting in loss of muscle tissue. Drug repurposing, i.e. using drugs already approved for other disorders, is attractive as it decreases development time. Recent studies suggested that simvastatin, a cholesterol lowering drug used for cardiovascular diseases, has beneficial effects on several parameters in mdx mice. To validate properly the effectiveness of simvastatin, two independent labs tested the effects of 12-week simvastatin treatment in either young (starting at 4 weeks of age) or adult (starting at 12 weeks of age) mdx mice. In neither study were benefits of simvastatin treatment observed on muscle function, histology or expression of genes involved in fibrosis, regeneration, oxidative stress and autophagy. Unexpectedly, although the treatment protocol was similar, simvastatin plasma levels were found to be much lower than observed in a previous study. In conclusion, in two laboratories, simvastatin did not ameliorate disease pathology in mdx mice, which could either be due to the ineffectiveness of simvastatin itself or due to the low simvastatin plasma levels following oral administration via the food. Show less
Greco, A.; Straasheijm, K.R.; Mul, K.; Heuvel, A. van den; Maarel, S.M. van der; Joosten, L.A.B.; ... ; Pruijn, G.J.M. 2021
Background: FSHD is caused by specific genetic mutations resulting in activation of the Double Homeobox 4 gene (DUX4). DUX4 targets hundreds of downstream genes eventually leading to muscle atrophy... Show moreBackground: FSHD is caused by specific genetic mutations resulting in activation of the Double Homeobox 4 gene (DUX4). DUX4 targets hundreds of downstream genes eventually leading to muscle atrophy, oxidative stress, abnormal myogenesis, and muscle inflammation. We hypothesized that DUX4-induced aberrant expression of genes triggers a sustained autoimmune response against skeletal muscle cells.Objective: This study aimed at the identification of autoantibodies directed against muscle antigens in FSHD. Moreover, a possible relationship between serum antibody reactivity and DUX4 expression was also investigated.Methods: FSHD sera (N=138, 48 +/- 16 years, 48% male) and healthy control sera (N=20, 47 +/- 14 years, 50% male) were analyzed by immunoblotting for antibodies against several skeletal muscle protein extracts: healthy muscle, FSHD muscle, healthy and FSHD myotubes, and inducible DUX4 expressing myoblasts. In addition, DUX4 expressing myoblasts were analyzed by immunofluorescence with FSHD and healthy control sera.Results: The results showed that the reactivity of FSHD sera did not significantly differ from that of healthy controls, with all the tested muscle antigen extracts. Besides, the immunofluorescent staining of DUX4-expressing myoblasts was not different when incubated with either FSHD or healthy control sera.Conclusion: Since the methodology used did not lead to the identification of disease-specific autoantibodies in the FSHD cohort, we suggest that autoantibody-mediated pathology may not be an important disease mechanism in FSHD. Nevertheless, it is crucial to further unravel if and which role the immune system plays in FSHD pathogenesis. Other innate as well as adaptive immune players could be involved in the complex DUX4 cascade of events and could become appealing druggable targets. Show less
Background: Natural history data are essential for trial design in Duchenne (DMD) and Becker muscular dystrophy (BMD), but recruitment for observational studies can be challenging.Objective: We... Show moreBackground: Natural history data are essential for trial design in Duchenne (DMD) and Becker muscular dystrophy (BMD), but recruitment for observational studies can be challenging.Objective: We reviewed reasons why patients or caregivers declined participation, and compared characteristics of participants and non-participants to assess possible selection bias in four observational studies, three on DMD and one on BMD.Methods: Three pediatric DMD studies focused on cross-sectional cognitive function and brain MRI (DMDbrain, n=35 and DMDperfusion, n = 12), and on longitudinal upper extremity function and muscle MRI (DMDarm, n = 22). One adult BMD study assessed longitudinal functioning (n = 36). Considerations for non-participation were retrospectively reviewed from screening logs. Age, travel-time, DMD gene mutations and age at loss of ambulation (DMDarm and BMD study only), of participants and non-participants were derived from the Dutch Dystrophinopathy Database and compared using nonparametric tests (p < 0.05).Results: The perceived burden of the protocol (38.2%), use of MRI (30.4%), and travel-time to the study site (19.1%) were the most frequently reported considerations for non-participation. Only few patients reported lack of personal gain (0.0–5.9%). Overall, participating patients were representative for the studied sub-populations, except for a younger age of DMDarm study participants and a complete lack of participants with a mutation beyond exon 63.Conclusion: Optimizing patient involvement in protocol design, improving MRI experiences, and integrating research into clinics are important factors to decrease burden and facilitate participation. Nationwide registries are essential to compare participants and non-participants and ensure representative observational research. Specific effort is needed to include patients with distal mutations in cognitive studies. Show less
In an minority of Myasthenia Gravis (MG) patients, the autoantibodies bind to muscle-specific kinase (MUSK). These MuSK antibody-mediated MG (MuSK MG) patients are not only immunologically distinct... Show moreIn an minority of Myasthenia Gravis (MG) patients, the autoantibodies bind to muscle-specific kinase (MUSK). These MuSK antibody-mediated MG (MuSK MG) patients are not only immunologically distinct, but also have different characteristic clinical features. Dysautonomia in MG is rarely reported. We present a MuSK MG patient who suffered from life-threatening autonomic dysfunction. MuSK MG should be considered in the differential diagnosis in cases of unclarified dysautonomia, given the potential for treatment in those cases. Show less
Introduction: The recently developed Myasthenia Gravis Impairment Index (MGII) is a promising measure as it has less floor effects and a higher relative efficiency in its responsiveness to... Show moreIntroduction: The recently developed Myasthenia Gravis Impairment Index (MGII) is a promising measure as it has less floor effects and a higher relative efficiency in its responsiveness to treatment effect compared to other MG measures. This study aimed at validating the MGII in a Dutch cohort of MG patients and analyzing the sensitivity of MGII compared to MG-ADL for changes in generalized weakness.Methods: We analyzed (generalized items of; -gen) MGII, quantitative myasthenia gravis (QMG), Myasthenia Gravis Activities of Daily Living (MG-ADL), EQ-5D visual analog, Myasthenia Gravis Composite (MGC) and ACTIVLIM (an ADL questionnaire focusing on generalized weakness) scores in a prospective cohort of 99 MG patients. We investigated correlations between MGII and other outcome measures. We used a generalized linear model to assess whether MGIIgen had an additional sensitivity on top of MG-ADLgen for changes (A) in QMGgen in individual patients.Results: MGII had a lower floor effect (4%) compared to QMG (6%), MG-ADL (11%) and MGC (16%). MGII correlated well with QMG (r = 0.68), MG-ADL (r = 0.83) and MGC (r = 0.74). As expected, the correlations with EQ visual analog and ACTIVLIM were lower (r = -0.57 and -0.48). AMGIIgen had an additional value on top of AMG-ADLgen in the prediction of Delta QMGgen (B = 0.54, p = 0.01).Discussion: The MGII score was cross-culturally validated in a Dutch cohort of MG patients. MGII had a higher sensitivity for generalized weakness than MG-ADL. Show less
Background: Natural history data are essential for trial design in Duchenne (DMD) and Becker muscular dystrophy (BMD), but recruitment for observational studies can be challenging.Objective: We... Show moreBackground: Natural history data are essential for trial design in Duchenne (DMD) and Becker muscular dystrophy (BMD), but recruitment for observational studies can be challenging.Objective: We reviewed reasons why patients or caregivers declined participation, and compared characteristics of participants and non-participants to assess possible selection bias in four observational studies, three on DMD and one on BMD.Methods: Three pediatric DMD studies focused on cross-sectional cognitive function and brain MRI (DMDbrain, n = 35 and DMDperfusion, n = 12), and on longitudinal upper extremity function and muscle MRI (DMDarm, n= 22). One adult BMD study assessed longitudinal functioning (n = 36). Considerations for non-participation were retrospectively reviewed from screening logs. Age, travel-time, DMD gene mutations and age at loss of ambulation (DMDarm and BMD study only), of participants and non-participants were derived from the Dutch Dystrophinopathy Database and compared using nonparametric tests (p < 0.05).Results: The perceived burden of the protocol (38.2%), use of MRI (30.4%), and travel-time to the study site (19.1%) were the most frequently reported considerations for non-participation. Only few patients reported lack of personal gain (0.0-5.9%). Overall, participating patients were representative for the studied sub-populations, except for a younger age of DMDarm study participants and a complete lack of participants with a mutation beyond exon 63.Conclusion: Optimizing patient involvement in protocol design, improving MRI experiences, and integrating research into clinics are important factors to decrease burden and facilitate participation. Nationwide registries are essential to compare participants and non-participants and ensure representative observational research. Specific effort is needed to include patients with distal mutations in cognitive studies. Show less
Lochmüller, H.; Ambrosini, A.; Van Engelen, B.; Hansson, M.; Tibben, A.; Breukel, A.; ... ; Willmann, R. 2019
Background: Duchenne muscular dystrophy (DMD) is characterized by progressive cardiomyopathy. Left ventricular (LV) function may worsen by factors increasing LV afterload such as hypertension and... Show moreBackground: Duchenne muscular dystrophy (DMD) is characterized by progressive cardiomyopathy. Left ventricular (LV) function may worsen by factors increasing LV afterload such as hypertension and obesity.Objective: To identify potential modifiable risk factors for progression of cardiomyopathy in Duchenne muscular dystrophy (DMD).Methods: We retrospectively analysed systolic blood pressures (SBP) and body-mass indexes (BMI) from 273 visits of 65 DMD patients aged 4-18 years between 2003 and 2016, divided in 14 age groups. Values were normalized using Z-scores (Z-SBP and Z-BMI). A linear mixed model was used to analyse correlations between Z-SBP and BMI, steroid use, age, ambulatory status and cardiac medication (CM) use. To study the relationship between SBP and BMI and myocardial deformation prior to the onset of clinical cardiomyopathy, LV deformation, defined by global longitudinal strain (GLS), was quantified in a subset of 36 patients <11 years. Multiple linear regression was used to study the relation between GLS and clinical parameters.Results: Median follow-up was 5 years. SBP was significantly elevated in all age groups under 14 years (p <= 0.04) and 15-16 years (p = 0.033) and correlated positively with BMI (p = 0.001) and negatively with CM use over time (p = 0.018). Z-BMI followed a bell-shaped distribution and plotted approximately one standard deviation above the mean in patients between 7 and 15 years. In the subset of younger patients, reduced GLS was associated with higher BMI ((beta = 0.348, p = 0.004).Conclusions: SBP and BMI may be potentially modifiable factors to retard deterioration of LV function in DMD. Show less