Cardioprotective medication in Duchenne muscular dystrophy: a single-centre cohort study

Background: Duchenne muscular dystrophy (DMD) is a neuromuscular disorder characterised by progressive muscle wasting impacting mobility, ventilation and cardiac function. Associated neuromuscular cardiomyopathy remains a major cause of morbidity and mortality. We investigated the effects of cardioprotective medications [angiotensin-converting enzyme inhibitors (ACE-I), beta-blockers] on clinical outcomes in DMD patients. Methods: This was a retrospective cohort study (reference: 2021/12469) of DMD patients at a tertiary centre between 1993–2021 screening the electronic records for demographics, comorbidities, medication, disease specific features, echocardiography, hospitalisations, and ventilator use. Results: A total of 68 patients were identified aged 27.4 (6.6) years, of which 52 were still alive. There was a difference in body mass index (BMI) between survivors and deceased patients [23.8 (5.9) vs. 19.9 (3.8) kg/m2, P=0.03]. Home mechanical ventilation (HMV) was required in 90% of patients, 85% had DMD associated cardiomyopathy. About 2/3 of all hospitalisations during the observation period were secondary to cardiopulmonary causes. The left ventricular ejection fraction (LVEF) at initial presentation was 44.8% (10.6%) and declined by 3.3% [95% confidence interval (CI): 0.4% to −7.0%] over the follow up period (P=0.002). A total of 61 patients were established on ACE-I for 75.9% (35.1%), and 62 were on beta-blockers for 73.6% (33.5%) of the follow up period. There was a significant LVEF decline in those taking ACE-I for limited periods compared to those permanently on ACE-I (P=0.002); a similar effect was recorded with beta-blockers (P=0.02). Conclusions: Long-term use of ACE-I and beta-blockers is associated with a reduced decline in LVEF in patients with DMD and may be protective of adverse cardiovascular ill health.