Myotonic dystrophy type 1 in the COVID-19 era.

INTRODUCTION: Myotonic dystrophy type 1 (DM1) is the most prevalent muscular dystrophy in adults. People with DM1 might represent a high-risk population for respiratory infections, including COVID-19. Our aim was to evaluate the characteristics of COVID-19 infection and vaccination rate in DM1 patients. METHODS: This cross-sectional cohort study included 89 patients from the Serbian registry for myotonic dystrophies. Mean age at testing was 48.4 ± 10.4 years with 41 (46.1%) male patients. Mean duration of the disease was 24.0 ± 10.3 years. RESULTS: COVID-19 infection was reported by 36 (40.4%) DM1 patients. Around 14% of patients had a more severe form of COVID-19 requiring hospitalization. The severity of COVID-19 was in accordance with the duration of DM1. A severe form of COVID-19 was reported in 20.8% of patients who were not vaccinated against SARS-CoV-2 and in none of the vaccinated ones. The majority of 89 tested patients (66.3%) were vaccinated against SARS-CoV-2. About half of them (54.2%) received three doses and 35.6% two doses of vaccine. Mild adverse events after vaccination were recorded in 20.3% of patients. CONCLUSIONS: The percentage of DM1 patients who suffered from COVID-19 was like in general population, but with more severe forms in DM1, especially in patients with longer DM1 duration. The study indicated an overall favorable safety profile of COVID-19 vaccines among individuals with DM1 and its ability to protect them from severe COVID-19.

COVID-19 and myotonic dystrophy: Case reports and systematic review.

INTRODUCTION: Steinert's disease is a rare genetic disorder characterized by progressive myotonia and multi-organ damage. It is associated with respiratory and cardiological complications often leading patients to exitus. These conditions are also traditional risk factors for severe COVID-19. SARS-CoV-2 has affected people with chronic diseases, but the impact on people with Steinert's disease is poorly defined, with only a few reported and described. More data are needed to understand whether this genetic disease is a risk factor for more serious evolution or death in patients with COVID-19. METHODOLOGY: The study describes two cases of patients with SD and COVID-19 and summarizes available evidence of the clinical outcome of COVID-19 in patients with Steinert's disease, by performing a systematic review of the literature (following PRISMA statements and performing PROSPERO registration). RESULTS: Overall, 5 cases were retrieved from the literature review, with a median age of 47 years, of whom 4 had advanced SD and unfortunately died. By contrast, the 2 patients from our clinical practice and 1 from literature had a good clinical outcomes. Mortality ranged from 57% (all cases) to 80% (only literature review). CONCLUSIONS: There is a high mortality rate in patients with both Steinert's disease and COVID-19. It highlights the importance of strengthening prevention strategies, especially vaccination. All SD with SARS-CoV-2 infection/COVID-19 patients should be identified early and treated to avoid complications. It is still unknown which treatment regimen is best to use in those patients. Studies on a greater number of patients are necessary to provide clinicians with further evidence.

Neuromuscular disease: 2023 update.

This review highlights ten important advances in the neuromuscular disease field that were reported in 2022. As with prior updates in this article series, the overarching topics include (i) advances in understanding of fundamental neuromuscular biology; (ii) new / emerging diseases; (iii) advances in understanding of disease etiology and pathogenesis; (iv) diagnostic advances; and (v) therapeutic advances. Within this general framework, the individual disease entities that are discussed in more detail include neuromuscular complications of COVID-19 (another look at the topic first covered in the 2021 and 2022 reviews), DNAJB4-associated myopathy, NMNAT2-deficient hereditary axonal neuropathy, Guillain-Barré syndrome, sporadic inclusion body myositis, and amyotrophic lateral sclerosis. In addition, the review highlights a few other advances (including new insights into mechanisms of fiber maturation during muscle regeneration and fiber rebuilding following reinnervation, improved genetic testing methods for facioscapulohumeral and myotonic muscular dystrophies, and the use of SARM1 inhibitors to block Wallerian degeneration) that will be of significant interest for clinicians and researchers who specialize in neuromuscular disease.

Safety and immunogenicity of mRNA COVID-19 vaccine in inpatients with muscular dystrophy.

INTRODUCTION/AIMS: Due to muscular weakness and cardiopulmonary dysfunction, patients with muscular dystrophy (MD) have an increased risk of serious complications from coronavirus disease-2019 (COVID-19). Although vaccination is recommended, COVID-19 vaccination safety and immunogenicity in these patients are unknown. We investigated reaction frequency, post-vaccine antibody titers after two mRNA COVID-19 vaccine doses, and clinical predictors of antibody response among patients with MD. METHODS: We recruited 171 inpatients with MD receiving two BNT162b2 mRNA COVID-19 vaccine doses from seven hospitals. Blood samples were obtained from 53 inpatients before the first dose and 28 to 30 days after the second dose, and antibody titers were measured. RESULTS: Overall, 104 (60.8%) and 115 (67.6%) patients had side effects after the first and second doses, respectively. These were generally mild and self-limited. Multiple logistic regression analysis showed that a bedridden state was associated with reduced side effects (odds ratio [OR] = 0.29; 95% confidence interval [CI], 0.12 to 0.71). The antibody titers of all participants changed from negative to positive after two vaccine doses. The geometric mean titer (GMT) of the inpatients was 239 (95% CI, 159.3 to 358.7). Older age (relative risk [RR] = 0.97; 95% CI, 0.95 to 0.99) and bedridden state (RR = 0.27; 95% CI, 0.14 to 0.51) were associated with a lower antibody titer. Patients with myotonic dystrophy type 1 (DM1) had a lower GMT than patients with other MDs (RR = 0.42; 95% CI, 0.21 to 0.85). DISCUSSION: COVID-19 vaccination is safe and immunogenic in inpatients with MD. Patients with DM1 appear to have a poorer COVID-19 antibody response than those with other MDs.

Clinical Features of the UK Myotonic Dystrophy Patient Registry

The UK Myotonic Dystrophy Patient Registry is a patient self-enrolling online database collecting clinical and genetic information about myotonic dystrophy type 1 (DM1) and type 2 (DM2). The registry was established in May 2012 with support from Muscular Dystrophy UK and the Myotonic Dystrophy Support Group and is coordinated Newcastle University. The registry aims to facilitate academic and clinical research, better characterise and understand DM, and disseminate information relating to upcoming studies and research advancements. The registry is used to capture longitudinal, selfreported data through an online portal available to patients and clinicians. Where specialised clinical or genetic information is required, the neuromuscular specialist involved in the patient's care can be invited to provide some additional information and the patient can select them from a pre-populated list at the registration stage. The registry is a Core Member of the TREAT-NMD Global Registries Network for DM1. Between May 2012 and January 2022, there were 834 patient registrations. On average there are 5 new registrations per month. For those reporting a clinical diagnosis, 96% have DM1 (of which 14% have a diagnosis of congenital DM) and 4% have DM2. Overall, 40% of patients have had genetic confirmation of their condition provided. The registry has previously supported almost 30 research enquiries to date. Since 2020, the registry has facilitated 11 enquiries including an industry enquiry, three COVID-19 surveys, and various surveys capturing information on dysphagia, pregnancy, patient preferences for future treatments and the patient/ caregiver experience. The registry continues to be a versatile, cost-effective research tool, helping facilitate and advance a range of DM research. Additional work continues to be done to improve reporting of genetic information on the registry and there are future data linkage plans between the registry and the Newcastle Research Biobank for Rare and Neuromuscular Diseases.

Myotonic dystrophy type 1 as a major risk factor for severe COVID-19?

The coronavirus disease 2019 (COVID-19) pandemic is challenging health care systems worldwide. People with myotonic dystrophy type 1 (DM1) represent a high-risk population during infectious disease outbreaks, little is known about the potential impact of COVID-19 on patients with DM1. We studied the clinical course of COVID-19 in three hospitalized patients with myotonic dystrophy type 1 or Steinert's disease, between April 1, 2020-April 30-2020. All three had advanced Steinert's disease receiving non-invasive nocturnal home ventilatory support. Two of them lived in a residential care centre. Two patients had a limited respiratory capacity, whereas one patient had a rather preserved functional capacity but more comorbidities. Two out of three patients were obese, none of them had diabetes mellitus. Two patients received hydroxychloroquine. Despite maximal supportive care with oxygen therapy, antibiotics, intensive respiratory physiotherapy and non-invasive positive pressure ventilation, all three patients eventually died due to COVID-19. Our case series of three patients with DM1 admitted for COVID-19 confirms that they are at high risk for severe disease and poor outcome. Clinical trials are needed to define best practices and determinants of outcomes in this unique population.