Uso de alendronato em pacientes com distrofia muscular de Duchenne
USA – neste estudo os autores demonstram que a osteoporose esta presente na distrofia muscular de Duchenne, que é progressiva. O diagnóstico precoce é benéfico e o uso de alendronato reduz a perda de massa óssea.
O resumo em inglês pode ser lido abaixo:
(Endocrine Review, 2012, 33) Low Bone Density and Effects of Alendronate Therapy in Patients with Duchenne Muscular Dystrophy
Caroline Houston, and Amal Shibli-Rahhal – USA
Background: Duchenne Muscular Dystrophy (DMD) is characterized by progressive muscle weakness that leads to loss of mobility by age 10 and death by age 20. Glucocorticoids are the mainstay of treatment, as they have been shown to slow disease progression. DMD patients develop low bone density as a result of glucocorticoid use and loss of mobility; however, little data exists to guide efforts towards screening for and treating low bone density in this population. We examined changes in bone density and the effects of alendronate therapy in DMD patients treated at the University of Iowa in the last decade.Methods: We conducted a retrospective cohort study of 39 patients with DMD for whom bone density data was available between December 2000 and September 2011. We examined baseline patient characteristics and bone density. We then assessed changes in bone density with alendronate therapy.Results: The mean patient age at the time of diagnosis was 3.5 years. Mean follow-up was 15.1 years. Ninety percent became wheelchair bound at a mean age of 10.6 years. Seventy-four percent were treated with glucocorticoids for an average period of 8.4 years. Seventy-two percent were treated with alendronate for an average period of 3.8 years.Patients received their first DXA scan an average of 8.5 years after diagnosis. Their bone density was low for their age, and the mean z-score was lower at the hip than at the lumbar spine (-3.27 versus -1.84, p < 0.0001). Patients treated with glucocorticoids received their first DXA scan sooner after diagnosis (7.7 versus 10.9 years), yet had lower z-scores at the lumbar spine (-2.04 versus -1.12, p = 0.0014). Among 8 patients who received multiple DXA scans prior to starting alendronate, the mean z-score at the hip declined from -2.85 to -3.04 (p = 0.70) over an average of 4.0 years. Among 18 patients treated with alendronate for an average of 3.0 years, mean z-scores increased at the hip (-3.31 to -3.25, p = 0.836) and lumbar spine (-2.09 to -1.80, p = 0.523).Conclusions: Patients with DMD develop low bone density that is more severe at the hip than the lumbar spine. Our patients were found to have low bone density 8.5 years after diagnosis and may have benefitted from earlier screening. Z-scores at the hip tended to decline with time prior to alendronate therapy. Z-scores at the hip and lumbar spine tended to improve with alendronate therapy. These trends were non-significant, likely due to small sample size.
