Endocrinology Considerations in Duchenne Muscular Dystrophy

DMD patient

While endocrinologists are not always part of a core DMD treatment team, their expertise is necessary, especially in handling the effects of long-term glucocorticoid therapy.

When the first Duchenne Muscular Dystrophy (DMD) Care Considerations were published in 2010, the guidelines and recommendations were intended to address the range of care a patient with DMD might need. But they largely omitted endocrinology concerns.

The updated Care Considerations – published in a general form earlier this year in Lancet Neurology, and in more detail this October in Pediatrics – remedy the lack of specific information for endocrinologists, and highlight how important the physicians are in treating the effects of long-term glucocorticoid therapy for these patients.

“Neurologists, cardiologists, pulmonologists and other specialists treat the symptoms of Duchenne itself, but there is not always the realization that as a result of therapy, Endocrinology may need to become involved,” says Garey Noritz, MD, chief of Complex Care at Nationwide Children’s Hospital and a co-author of both the general and endocrine-specific DMD Care Considerations.

Dr. Noritz was also senior author of the P.J. Nicholoff Steroid Protocol in 2017, an effort to help clinicians recognize and prevent acute adrenal crisis for patients with DMD who receive emergency care.

“Endocrinologists are often consulted if there’s a rheumatologic condition or a gastrointestinal condition that requires long-term steroid therapy. That should be the case with Duchenne as well,” Dr. Noritz says.

Glucocorticoid therapy is now a standard DMD treatment and has helped patients live longer with a higher quality of life. Patients with DMD are already at risk of obesity and growth failure, however, and glucocorticoid therapy can exacerbate those problems and lead to osteoporosis, delayed puberty and adrenal insufficiency.

The publication includes flow charts and tables to guide the referral of patients to endocrinologists when they experience certain obesity related comorbidities such as hyperglycemia; when they meet certain thresholds of delayed growth, such as a height of less than the 3rd percentile for age; and when they demonstrate delayed puberty, such as having a testicular volume of less than 4 cubic centimeters at 14 years of age.

The publication also makes recommendations to endocrinologists of appropriate assessment and treatment of delayed puberty, impaired growth and management of adrenal suppression. Endocrinologists have an important role to play in the management of low bone density as well, says Dr. Noritz.

Even before those downstream effects of DMD and glucocorticoid therapy, a DMD care team would be wise to work with Endocrinology colleagues, says Dr. Noritz. “Prescriber counseling” is an important part of initiating steroid therapy, and endocrinologists are perhaps best equipped to inform families not only of the long-term effects but also about warning signs of adrenal suppression and crisis.

References:

Weber DR, Hadjiyannakis S, McMillan HJ, Noritz G, Ward LM.  Obesity and endocrine management of the patient with Duchenne muscular dystrophy. Pediatrics. 2018 Oct; 142(Suppl 2):S43-S52.

Birnkrant DJ, Bushby K, Bann CM, Apkon SD, Blackwell A, Colvin MK, Cripe L, Herron AR, Kennedy A, Kinnett K, Naprawa J, Noritz G, Poysky J, Street N, Trout CJ, Weber DR, Ward LM; DMD Care Considerations Working Group. Diagnosis and management of Duchenne muscular dystrophy, part 3: primary care, emergency management, psychosocial care, and transitions of care across the lifespan. Lancet Neurology. 2018 May; 17(5): 445-455.

 Kinnett K, Noritz G. The PJ Nicholoff Steroid Protocol for Duchenne and Becker muscular dystrophy and adrenal suppression. PLOS Currents. 2017 Jun 27; 9.