Myotonic dystrophy family registry. The patient experience.

IntroductionThe Myotonic Dystrophy Family Registry (MDFR) is a disease-specific, patient-reported online registry designed to capture real-world data on disease burden and lived experience in myotonic dystrophy (DM). By integrating patient-reported data with mechanisms for participant engagement, the MDFR provides a platform to characterize disease heterogeneity and support clinical research and trial readiness.AimsTo characterize patient-reported disease burden and registry participation in DM, and to explore associations between disease subtype, age-related variables, and repeat expansion length.MethodsDe-identified MDFR data collected between 2013 and 2024 were aggregated and analyzed. Patient demographics and symptom prevalence were tested for associations between DM subtype, age, and repeat expansion length.ResultsThe analysis demonstrated substantial, age-dependent disease burden in both DM1 and DM2, with multisystem involvement across central nervous system, cardiac, pulmonary, visual, and neuromuscular domains. Daytime sleepiness, myotonia, and fatigue were among the most frequently reported manifestations. Significant genotype-phenotype associations were identified in DM1, with CTG repeat length associated with increased prevalence of motor, cardiac, and central nervous system manifestations.ConclusionsPatient-reported data from the MDFR provide complementary insights into disease burden and heterogeneity in DM, including domains that may be underrepresented in clinically derived datasets. Going forward, these findings support the integration of patient-reported, clinical, and genetic data to improve disease characterization, inform clinical trial design, and advance therapeutic development. Continued efforts to harmonize and expand longitudinal data collection and standardize data elements will be important to enhance the utility of registries.