Del Rocio Cruz-Guzman O, Rodriguez-Cruz M, Almeida-Becerril T, Maldonado-Hernandez J, Baeza CW. Muscle function and age are associated with loss of bone mineral density in Duchenne muscular dystrophy. Muscle & nerve 2019;59:417-421
In this study was found that the loss of bone density seen in DMD patients, is related to both age and reduction in muscle function. The study, however, neglects that, since muscle function decreases with age, that if one is correlated with loss of bone density, it is likely the other one also shows a correlation.
INTRODUCTION: Patients with Duchenne muscular dystrophy (DMD) demonstrate decreased bone mineral density (BD). It is not clear which factors exert the greatest impact on BD loss in these patients.
METHODS: In 63 patients with DMD, serum cytokines (IL-1, IL-6, and TNF-), C-reactive protein (CRP), creatine kinase (CK), muscle function (by Vignos Scale), body composition, and total BD (the latter two measured by dual-energy x-ray absorptiometry, or DEXA) were determined.
RESULTS: The main factors associated with BD loss were muscle function (34.0%, beta = -0.139; p <0.023) and age (36.7 %, beta = -0.151; p = 0.004). Cytokines, CRP, body fat mass and CK did not contribute to BD loss.
DISCUSSION: Muscle function and age contribute to BD loss in DMD. We propose that a cut-off of >/=6 points for the Vignos Scale and of >/=10.5 years of age predict a Z-score of </=-2.0. This article is protected by copyright. All rights reserved.