Report of a Muscular
Dystrophy Campaign funded workshop Birmingham, UK, January 16th 2004.
Osteoporosis in Duchenne muscular dystrophy; its prevalence, treatment and
prevention
R. Quinlivan, H. Roper, M. Davie, N.J. Shaw, J.
McDonagh, K. Bushby - UK
Neuromuscular Disorders, 2004
11. Conclusions and recommendations
11.1. DMD and osteoporosis
Duchenne muscular dystrophy leads to reduced
mobility, which is associated per se with an increased chance of fractures and
reduced bone mineral density. Bone mineral density, especially in the spine is
further reduced by longterm steroid treatment. The development of vertebral
fractures is dependent upon the cumulative steroid dose and the risk may be
very high for those children receiving long-term steroids. The investigation of
bone mineral density in children can be problematic and care is needed in the
interpretation of data, however, individual children can act as their own
controls. DXA scanning can therefore be used to monitor bone mineral density in
an individual patient, but there is no clear relationship between a particular
Z score and risk of fracture, and DXA results alone should not be used to
change practice or lead to specific treatment. When developing randomised
controlled treatment trials, different centres may not have compatible DXA
machines or software but this can be often overcome using statistical methods
for correction.
11.2. Prevention of complications
Fig. 1 is a schematic outline of the proposed management
plan agreed by the group. Preserving muscle function will protect long bones,
prolonging walking and standing is an important element of management. Sunshine
and nutrition are extremely important in maintaining healthy bones and care
must be taken to ensure optimal exposure. There is a lack of published evidence
for the prevention of vertebral fractures using calcium and vitamin D
supplements, there is no evidence based indication to prescribe supplements
alongside steroids unless there is a demonstrated deficiency or unless dietary
manipulation is not possible.
When commencing steroids in children with
DMD, it is prudent to check the 25OH vitamin D levels before treatment. All
children should be referred to a dietician in order to optimise the dietary
calcium and vitamin D intake. If the 25OH vitamin D levels are low, the
clinician may wish to consider treatment with calcium and vitamin D
supplements. A baseline DXA scan to assess bone mineral density is probably
advisable with follow up scans every 1–2 years, however, at the moment there is
no consensus on how to manage worsening bone mineral density in an individual
child in the absence of a vertebral fracture. More research is required to
establish the long-term effects of bisphosphonates in children, the most
effective dose and frequency of treatment, especially oral treatment, before
they can be recommended for prophylactic use.
11.3. Treatment of complications
Any patient receiving steroids who complain
of back pain should have X-rays (Anterior, Posterior, and Lateral) of the spine
taken and if a vertebral fracture is evident urgent referral to a metabolic
bone specialist for intravenous bisphosphonate treatment is indicated. Under
these circumstances it is not necessary to stop steroid treatment. In the
presence of a long bone fracture, a common complication in DMD, no
pharmacological treatment is required unless a silent vertebral fracture is
discovered on a lateral spine X-ray.