Age of Onset, Functional Status, and Quality of Life Outcomes in Patients with Congenital and Childhood-Onset Myotonic Dystrophy Type 1 (P3.6-069)

Objective: To determine if the quality of life of congenital and childhood-onset myotonic dystrophy type 1 (DM1) patients differs with age of onset, ambulatory status, and functional progress. Background: DM1 is a devastating multisystem disease for which treatment is solely supportive. Finding the greatest areas of burden on quality of life is therefore important in best directing available therapies. Design/Methods: This study was a retrospective analysis of electronic health records of DM1 patients attending the Cincinnati Children’s Hospital Medical Center Comprehensive Neuromuscular Care Canter from January 1, 2012 until June 1, 2018. The primary outcome measure was patient-reported quality of life. The PedsQL™ 4.0 Generic Core Scale measures emotional, physical, school, and social functioning, while the PedsQL™ 3.0 Neuromuscular Module measures family resources, disease severity, and communication ability. Secondary outcome measures included age of onset, ambulation status, and motor function progress. Inclusion criteria included a confirmed diagnosis, evident symptoms, and genetic confirmation of DM1, along with completion of at least one quality of life survey at a clinic visit. Thirty-two DM1 patients were included: 18 congenital and 14 childhood-onset. Results: Congenital DM1 patients rated their overall quality of life significantly lower than patients in the childhood-onset cohort (p = 0.049). Additionally, congenital-onset patients scored lower in both parent- and patient-reported health and activities (p = 0.001 and p = 0.005, respectively). When motor function progress was studied amongst all patients, all parent-reported PedsQL™ 4.0 Generic Core Scale domains were significantly lower in the declining group versus the stable or improving group. In congenital-only analyses, neither motor function progress nor ambulatory status significantly impacted quality of life. Conclusions: This study demonstrates that patients with congenital DM1 experience a lower quality of life than those with childhood-onset of disease. It also demonstrates that worse physical functioning negatively impacts quality of life in DM1 patients. Disclosure: Dr. Kelder has nothing to disclose. Dr. Horn has nothing to disclose. Dr. Bange has nothing to disclose. Dr. Rybalsky has received research support from Pfizer, BMS, Roche, Fibrogen, PTC, and Sarepta. Dr. Tian has received research support from Pfizer, BMS, Roche, Fibrogen, PTC, Sarepta.