Background
Duchenne muscular dystrophy (DMD) is a progressive X-linked neuromuscular disorder caused by dystrophin deficiency, resulting in muscle weakness and loss of ambulation. Corticosteroids, including prednisone, prednisolone, and deflazacort, are central to DMD management, helping slow disease progression and preserve motor function. However, the long-term effects on motor, respiratory, and cardiac outcomes remain unclear. This review and meta-analysis examine the longitudinal outcomes of corticosteroid therapy in DMD.
Objectives
To assess the impact of corticosteroids on motor, respiratory, cardiac function, and adverse effects in DMD. Secondary objectives include evaluating the efficacy, safety, and influence on quality of life of different corticosteroid regimens.
Methods
A systematic review and meta-analysis following PRISMA guidelines was conducted. Searches of PubMed, Embase, Cochrane Library, and ClinicalTrials.gov identified randomized controlled trials (RCTs), non-randomized trials, and longitudinal studies. Data extraction was performed by two independent reviewers. Meta-analyses were done using random-effects models in R and Python. The GRADE approach assessed evidence quality.
Results
Eighteen studies with 1,245 participants were included. Corticosteroid therapy delayed loss of ambulation by 2.1 years. NSAA scores were better maintained in treated groups, especially when treatment began before age 7. Pulmonary function declined slower, with an annual reduction of 0.8% in FVC. Cardiac outcomes showed mixed results, but deflazacort was suggested to offer superior cardioprotection. Adverse effects included weight gain, growth delay, and vertebral fractures. Quality of life improved with slower disease progression, though side effects raised concerns.
Conclusion
Corticosteroids are effective in preserving motor and respiratory function in DMD. Deflazacort may provide cardioprotective benefits, but more research is needed. Personalized treatment approaches could optimize outcomes and minimize adverse effects.