In January 2005, the American Academy of Neurology (AAN) released its long-awaited report on the use of corticosteroids (prednisone or deflazacort) in Duchenne muscular dystrophy (DMD). The report is also published in the Jan. 11 issue of Neurology. It finds that corticosteroids are beneficial in DMD, but that some drawbacks to their use must be considered. To see the report for physicians and a version for families, visit “Practice Guidelines” on the AAN website.
Known as a practice parameter, the report results from a review of relevant articles published from 1966 to 2004, of which 25 were chosen for detailed analysis. The AAN subcommittee preparing the report was composed mostly of MDA clinic directors and research grantees. Several of the 25 selected studies received MDA funding. The report concluded that:
- Prednisone and deflazacort (the latter isn't available in the United States) are beneficial in the treatment of DMD. Seven high-quality studies showed a significant increase in strength, timed muscle function and pulmonary function with these medications.
- Effective initial treatments are 0.75 milligrams per kilogram of body weight per day for prednisone, or 0.9 milligrams per kilogram per day for deflazacort.
- The most frequent side effects are weight gain and the development of a Cushingoid facial appearance (rounded, puffy face).
- There are insufficient data comparing prednisone and deflazacort to determine whether deflazacort has fewer side effects.
The subcommittee’s recommendations included:
- Maintaining a daily dosage of 0.75 milligrams of prednisone per kilogram is best, but if side effects require a decrease in dosage, a gradual tapering to as low as 0.3 milligrams will still provide some improvement.
- Benefits and side effects of corticosteroid therapy need to be monitored. Timed function tests, pulmonary function tests, and age at loss of independent walking are useful to assess benefits. An offer of treatment with corticosteroids should include a discussion of risks.
- Possible side effects, such as weight gain, Cushingoid appearance, cataracts, short stature from slowed growth rate, acne, excessive hair growth, gastrointestinal symptoms and behavioral changes, need to be assessed. If a boy gains more than 20 percent over the estimated normal weight for his height in a year, the dosage of prednisone should be decreased to 0.5 milligrams per kilogram per day, with a further decrease to 0.3 milligrams after three to four months if excessive weight gain continues.
- Deflazacort at 0.9 milligrams per kilogram per day can also be used for the treatment of DMD in countries where it’s available. Patients taking deflazacort should be monitored for cataracts and weight gain.
Valerie Cwik, MDA’s chief medical and scientific officer, said that while the guidelines are useful, they also identify many questions about corticosteroid therapy and DMD that remain unanswered.
©2005, Muscular Dystrophy Association