As of yet, there's no cure for Duchenne muscular dystrophy
— only attempts at dampening the progressive muscle
wastage. One treatment strategy is to use the immune-muting
prowess of corticosteroids. Side effects of these drugs
can be as mild as weight gain and a spot of acne. But
when you add intestinal upset and behavioural changes
to the list, it's enough to give most doctors pause before
prescribing these drugs. Despite the litany of side effects
that have put a question mark over the use of corticosteroids,
a report in the January 11 issue of Neurology recommends
them to slow the progression of muscle weakness in these
patients.
Practice guidelines from the Quality
Standards Subcommittee of the American Academy of Neurology
and the Practice Committee of the Child Neurology Society
advocate prednisone use saying that it "has been demonstrated
to have a beneficial effect on muscle strength and function
in boys with Duchenne dystrophy and should be offered
as treatment." Deflazacort — another corticosteroid
that's similar to prednisone — also received two-thumbs
up. Unfortunately, this drug isn't available yet in
Canada.
HOW
LOW CAN YOU GO?
The available relevant literature on the use of corticosteroids
in the treatment of this disease showed that a six-month
course of prednisone (0.75 or 1.5mg/kg/day) "increased
muscle strength, performance, and pulmonary function
and significantly slowed the progression of weakness."
Two trials that studied the effects of lower levels
of prednisone revealed that "tapering to dosages as
low as 0.3mg/kg/day gives less robust but significant
improvement."
Other options to quell the discomfort
and muscle wasting of Duchenne muscular dystrophy include
physical therapy, devices to support weak muscles and
even surgery. All these are more invasive and cumbersome
than the drug route. So, the latest practice guideline
offers clinicians some ammunition in opting for corticosteroids.
Nonetheless the guidelines still
advocate caution. "If the side effects outweigh the
benefits, it is recommended to lower the dose of the
drugs," commented lead author Dr Richard Moxley, III,
of the University of Rochester in the state of New York.
On the other hand he concedes that "if the dose is decreased,
the level of improvement in muscle strength and function
may not be as great."
Neurology Jan 11, 2005;64:13-20
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