Abstract

This study aimed to evaluate glucose tolerance in adult males with Becker muscular dystrophy (BMD) and Duchenne muscular dystrophy (DMD) using an oral glucose tolerance test (OGTT). The study investigated whether body composition influences glucose response.

• Participants: 28 adults with dystrophinopathy (13 BMD, 15 DMD) and 12 non-dystrophic controls.
• Method: 75g glucose ingestion with fingertip blood sampling every 30 minutes for 2 hours.
• Results: Higher glucose levels in MD groups compared to controls at 60, 90, and 120 minutes.
• Conclusion: Routine glucose tolerance assessments are crucial for early detection of impaired glucose tolerance (IGT) in these populations.

Introduction

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are genetic disorders resulting from mutations in the dystrophin gene. DMD is characterized by a complete absence of dystrophin, whereas BMD involves partially functional dystrophin.

Methods

• Participants: 28 adults with dystrophinopathy (13 BMD, 15 DMD) and 12 healthy controls.
• Test: OGTT (75g glucose), glucose measured at 0, 30, 60, 90, and 120 minutes.
• Body Composition Analysis: Bioelectrical impedance analysis (BIA) and muscle size measurement via B-mode ultrasonography (vastus lateralis muscle).

Results

• Higher Blood Glucose Levels: MD groups showed significantly higher glucose levels than controls at 60, 90, and 120 minutes.
• Lower Fat-Free Mass (FFM): FFM relative to body mass (FFM/BM) and vastus lateralis muscle cross-sectional area (VL ACSA) were significantly lower in the MD groups.
• Correlation: Glucose tolerance at 120 minutes correlated with FFM/BM and body fat percentage in BMD participants.
• Impaired Glucose Tolerance (IGT): Identified in 53% of DMD and 46% of BMD participants, but none in controls.

Discussion

This study highlights marked impairment in glucose tolerance in adults with DMD and BMD. The impairment is potentially due to reduced muscle mass and increased adiposity. Regular glucose monitoring is essential to prevent and manage metabolic complications.

Conclusion

Adults with Duchenne and Becker muscular dystrophy exhibit significantly impaired glucose tolerance compared to healthy controls. This highlights the importance of routine OGTTs for early detection and intervention to mitigate long-term metabolic risks in patients with dystrophinopathies.