Tratamento da osteoporose na distrofia muscular de Duchenne com bifosfonados injetáveis

Canadá - esta pesquisa foi apresentada no congresso anual da Sociedade de Endocrinologia - ENDO-2010. A osteoporose é frequente em Duchenne, em especial nos que usam corticóides. A osteoporose predispõe a fraturas e o uso de bifosfonados é recomendado com tratamento para esta condição. Nesta pesquisa os autores testaram o uso de pamidronato ou zoledronato por via venosa (ambas as drogas são dadas uma vez por ano) em 7 meninos com Duchenne e fraturas em coluna, O tratamento com a droga mostrou-se eficaz com aumento da densidade óssea e redução das dores decorrentes das fraturas. Os efeitos colaterais observados foram febre (2 casos), náuseas (2 casos), dores musculares (3 casos) e hipocalcemia (2 casos).

O resumo em inglês pode ser lido abaixo:

(Annual Meeting Endocrinology Society - ENDO-2010) Effect of Intravenous Bisphosphonate Therapy among Boys with Duchenne Muscular Dystrophy and Osteoporosis: Clinical Outcomes.

AM Sbrocchi, F Rauch, V Konji, M Tomiak, P Jacob, LM Ward. Children's Hosp of Eastern Ontario, Ottawa, Canada; Shriners Hosp for Children, Montreal, Canada.

Introduction: Boys with Duchenne Muscular Dystrophy (DMD) may develop symptomatic vertebral fractures. Bisphosphonates have been used to treat the spine fragility; however, detailed analyses of the response to therapy are lacking. The objective of this study was to assess the efficacy and safety of IV bisphosphonate treatment in boys with spinal osteoporosis due to DMD.
Methods: This was a one-year, retrospective observational study of 7 boys (age 8.5-14.3 years) with DMD who had received either IV pamidronate (9 mg/kg/year) or zoledronate (0.1 mg/kg/year) to treat painful vertebral fractures. The primary outcome was change in vertebral morphometry at 12 months post-bisphosphonate initiation. Secondary outcomes included back pain status, changes in lumbar spine volumetric bone mineral density (vBMD), and adverse events.
Results: A description of the cohort is presented in the Table. All but one had received glucocorticoid therapy prior to treatment initiation, and all but one was non-ambulatory. There were 27 fracture events noted in the 7 patients at baseline; 15/27 were in the T4-T9 region. Grade 2 (moderate) and Grade 3 (severe) vertebral fractures reconstituted at 12 months, and this was associated with either improvement or complete resolution of back pain. The median spine vBMD also increased. First-dose side effects were present in 4 patients and included fever (N=2), nausea (N=2), myalgias (N=3) and hypocalcemia (N=2).
Conclusion: In boys with spinal osteoporosis and DMD, IV bisphosponate therapy administered over 12 months was associated with improved vertebral morphometry and density; similarly, there was amelioration in back pain. The therapy was generally well-tolerated.

Table. Clinical Parameters Pre- and 12 Months Post-Treatment

Values reported are median (min, max) unless otherwise specified. VH=Vertebral height, BMD= Bone mineral density.

Fonte: http://distrofiamuscular.net/noticias.htm