Impact of bisphosphonates on survival for patients with Duchenne muscular dystrophy

OBJECTIVE: In this article we describe the association of bisphosphonate therapy on survival within a regional cohort of patients with Duchenne muscular dystrophy (DMD) who received steroid therapy and were managed in a single center. PATIENTS AND METHODS: The records of all patients with confirmed DMD who were born between 1963 and 2006 and who had received at least 1 year of steroid therapy were reviewed from birth until they reached the study end points (death, loss to follow-up, or the last follow-up was in 2009). A survival analysis was used to account for the variable follow-up duration within this cohort. RESULTS: Forty-four boys from this cohort with DMD were exposed to continuous steroid use. Bisphosphonate therapy was initiated for 16 patients (36%) between 1997 and 2007 at a median age of 12.5 years (range: 7-23 years). At the time of the last follow-up in 2009, 13 patients had died (30%) at a median age of 16 years (range: 14-27 years). Survival curves demonstrate that the prescription of bisphosphonates was associated with a significant improvement in survival rate (P = .005, log-rank test). Furthermore, a possible therapy-duration effect could be shown for bisphosphonate use (P = .007, log-rank test). CONCLUSIONS: The treatment of patients with DMD with steroids and bisphosphonates seems to be associated with significantly improved survival compared with treatment with steroids alone.