COOPERATIVE INTERNATIONAL NEUROMUSCULAR RESEARCH GROUP DUCHENNE NATURAL HISTORY STUDY DEMONSTRATES INSUFFICIENT DIAGNOSIS AND TREATMENT OF CARDIOMYOPATHY IN DUCHENNE MUSCULAR DYSTROPHY

Introduction: Cardiomyopathy is a common cause of morbidity and death in patients with Duchenne muscular dystrophy (DMD). Methods: This investigation was a cross-sectional cross-sectional analysis of clinical data from the multi-institutional Cooperative International Neuromuscular Research Group (CINRG) DMD Natural History Study of 340 DMD patients aged 2-28 years. Cardiomyopathy was defined as shortening fraction (SF) <28% or ejection fraction (EF) <55%. Results: Two hundred thirty-one participants reported a prior clinical echocardiogram study, and 174 had data for SF or EF. The prevalence of cardiomyopathy was 27% (47 of 174), and it was associated significantly with age and clinical stage. The association of cardiomyopathy with age and clinical stage was not changed by glucocorticoid use as a covariate (P>0.68). In patients with cardiomyopathy, 57% (27 of 47) reported not taking any cardiac medications. Cardiac medications were used in 12% (15 of 127) of patients without cardiomyopathy. Conclusions: We found that echocardiograms were underutilized, and cardiomyopathy was undertreated in this DMD natural history cohort.