Is ongoing testosterone required after pubertal induction in Duchenne muscular dystrophy?

Area of Science:

• Pediatric Endocrinology
• Neuromuscular Disorders

Background:

• Glucocorticoids (GC) are used to manage inflammation and muscle function in Duchenne muscular dystrophy (DMD), but they can delay puberty.
• Testosterone therapy is recommended for pubertal induction in these patients, but long-term outcomes require further investigation.

Purpose of the Study:

• To evaluate the long-term effects of testosterone therapy on the hypothalamic-pituitary-gonadal (HPG) axis, muscle volume, and function in boys with DMD up to 5 years after pubertal induction.

Main Methods:

• A prospective observational follow-up study involved 15 GC-treated males with DMD who received incremental testosterone therapy for 2 years.
• Assessments included testicular volume (TV), gonadotrophins, testosterone, inhibin B, muscle function, and limb muscle MRI at 2.5 and 5 years post-treatment.

Main Results:

• Testosterone levels remained stable at 5 years post-treatment. Testicular volume and Inhibin B levels significantly increased, indicating HPG axis activation, though Inhibin B remained below reference values.
• While testosterone and testicular volume improved, muscle contractile bulk decreased over the follow-up period.

Conclusions:

• Testosterone therapy in DMD patients is associated with HPG axis activation and improved reproductive hormone profiles, offering potential benefits for fertility.
• Monitoring and supplementing testosterone levels are crucial given its positive effects on bone health, muscle, and overall well-being in this population.