Background: Cardiac disease is a major contributor to morbidity and mortality in patients with Duchenne and Becker muscular dystrophy (MD).
Objectives: Characterize the burden of cardiac disease and management in pediatric MD.
Methods: Males <18y at time of first claim for MD (index date) with continuous enrollment for ≥12 months post-index date were identified from the MarketScan Database (2013-2018). Healthcare resource use were summarized using descriptive statistics and reported per patient per year (PPPY).
Results: 1341 patients were included with a median follow-up of 2.8y (IQR 1.8, 4.3). 295 (22%) were 1-6y, 494 (37%) 7-12y, and 552 (41%) 13-18y at index date. 72 (5.4%) had heart failure with a higher prevalence in the 13-18y group (7%, n=38) compared to the 1-6y (1.7%, n=5) (p=0.001), but not the 7-12y group (6%, n=29) (p=0.50). 568 (42%) of patients had ≥1 outpatient cardiology visits PPPY, including only 244 (44%) of patients in the 13-18y group. The median number of cardiology visits amongst patients with >1 outpatient cardiology visit PPPY was higher in the 13-18y group (median 1.1, IQR [0.7-1.7]) compared to the 7-12y (0.9, IQR [0.5-1.3]) (p=0.0002) and 1-6y group (0.7, IQR [0.4-1.3]) (p=0.0001). 379 (28%) had ≥ 1 echocardiograms (echo) PPPY with the highest rate in the 13-18y group (35%, n=191) compared to the 7-12y (28%, n=136) (p=0.026) and 1-6y group (18%, n=52) (p<0.001). 31% (n=420) did not have an echo. Ambulatory rhythm monitoring was infrequent, observed in 19% of the cohort.
Conclusions: Visits and echos increased with age among patients with ≥1 visit PPPY, which parallels an increased heart failure prevalence with age. However, over half of patients in the 13-18y group did not have yearly cardiac follow up or echocardiograms, and 81% of the study group did not undergo ambulatory rhythm monitoring. Significant changes to management are needed in order to observe updated Duchenne MD Care Considerations and optimize cardiac outcomes.