Treatment of Becker Muscular Dystrophy
Becker Muscular Dystrophy (BMD) requires a multidisciplinary approach focusing on glucocorticoid therapy, cardiac monitoring, respiratory care, and rehabilitation to improve quality of life and reduce mortality. 1
Core Treatment Components
Medication Management
- Glucocorticoid Therapy:
- First-line treatment to slow decline in muscle strength and function
- Options: prednisone/prednisolone (0.75 mg/kg/day) or deflazacort (0.9 mg/kg/day)
- Continue therapy even after loss of ambulation to slow scoliosis progression, decline in pulmonary function, and delay heart failure 1
Cardiac Care
- Early Cardiac Therapy:
Respiratory Management
- Regular pulmonary function testing to monitor disease progression
- Early introduction of nocturnal ventilation when indicated
- Proactive discussion about mechanical ventilation options before urgent need arises 1
- Respiratory care becomes increasingly important as disease progresses 2
Rehabilitation and Physical Therapy
- Regular physical therapy to maintain muscle extensibility and minimize contractures
- Appropriate exercise within tolerance limits:
- Adaptive devices for mobility and function as needed 1
Supportive Care
Bone Health Management
- Monitor vitamin D levels annually (25-hydroxy vitamin D)
- Supplement with vitamin D3 if levels are <32 nmol/L
- Ensure adequate calcium intake
- Consider bisphosphonates (e.g., pamidronate) if fracture risk is high 1
Orthopedic Care
- Monitor for scoliosis and joint contractures
- Consider surgical options for contractures in specific situations
- Ensure proper wheelchair positioning with appropriate foot support
- Custom orthotic insoles to improve biomechanics and reduce pressure points 1
Nutritional Support
- Regular monitoring of weight
- Nutritional assessment for both underweight and overweight concerns
- Attention to potential swallowing difficulties with dietary modifications as needed 1
Psychosocial Support
- Assessment and intervention for coping strategies
- Promotion of independence and social development
- Educational support through individualized education programs
- Preparation for transition to adult services 1
Disease Monitoring
Initial Assessment
- Genetic testing to confirm BMD diagnosis
- Comprehensive assessment including:
- Muscle strength and range of motion evaluation
- Cardiac function assessment via echocardiogram
- Pulmonary function testing
- Bone density scan (DEXA)
- Serum creatine kinase muscle isoforms 1
Follow-up Assessments
- Muscle strength and range of motion evaluation every 6 months
- Cardiac monitoring every 1-2 years, more frequently if abnormalities detected
- Annual pulmonary function testing
- Regular assessment for complications 1, 4
Important Considerations
Genotype-Phenotype Correlation
- Specific DMD mutations may predict disease severity and progression
- Patients with del45-49 tend to have earlier loss of ambulation
- Patients with del45-55, del48, and del48-49 typically have later loss of ambulation
- del45-55 and del48 are associated with decreased odds of developing pathological left ventricular ejection fraction 4
Female Carriers
- Require cardiac monitoring as they may develop mild to moderate dilated cardiomyopathy in their fifth decade 1
Common Pitfalls to Avoid
- Discontinuing glucocorticoids prematurely despite side effects
- Neglecting cardiac care in asymptomatic patients
- Overlooking respiratory support needs
- Focusing only on muscle strength while ignoring other affected systems 1
- Prescribing high-intensity exercise which can accelerate muscle damage 3
BMD management requires coordinated care from neurology, cardiology, pulmonology, rehabilitation medicine, orthopedics, and psychology to optimize outcomes and quality of life.