TBS as a Tool to Differentiate the Impact of Antiresorptives onCortical and Trabecular Bone in Children With OsteogenesisImperfecta

J Clin Densitom. 2019 Apr-Jun;22(2):229-235. doi: 10.1016/j.jocd.2018.09.001. Epub 2018 Sep 8.

Abstract

Introduction/background: Osteogenesis imperfecta is a hereditary connective tissue disorder, resulting in low bone mass and high bone fragility. Dual-energy X-ray absorptiometry (DXA) and in adulthood also the trabecular bone score (TBS) are well established to assess bone health and fracture risk. The purpose of this investigation was to assess the usefulness of TBS in respect to different treatment regimes in children with osteogenesis imperfecta. Changes of areal bone mineral density (aBMD) and TBS using DXA scans of children treated with antiresorptive therapies were evaluated.

Methodology: DXA scans (aBMD, TBS) of 8 children with OI were evaluated. The scans were taken during a 1 yr period of treatment with bisphosphonates and during 1 yr pilot trial using denosumab. Changes of aBMD and TBS during both treatment regimens were compared.

Results: During bisphosphonate treatment aBMD increased about 6.2%, while TBS increased about 2.1%. The difference between aBMD and TBS before and after bisphosphonate treatment was not significant (p = 0.25). During denosumab treatment aBMD increased around 25.1%, while TBS increased 6.7%. The change of aBMD was significant (p = 0.007), as was the difference between aBMD and TBS (p < 0.001).

Conclusions: Denosumab had a significant effect on both aBMD and TBS but was significantly more pronounced in aBMD. These results suggest a stronger effect of denosumab on cortical bone and the growth plate in comparison to bisphosphonates. Beside the lack of paediatric reference data and the small sample size, the results suggest TBS to be a useful tool for monitoring skeletal changes during development, growth, and antiresorptive therapy in children with OI.

Keywords: Bone mineral density; Osteogenesis imperfecta; Retrospective trial; Trabecular bone score.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorptiometry, Photon
  • Bone Density
  • Bone Density Conservation Agents / therapeutic use*
  • Cancellous Bone / diagnostic imaging*
  • Child
  • Child, Preschool
  • Cortical Bone / diagnostic imaging*
  • Denosumab / therapeutic use*
  • Diphosphonates / therapeutic use*
  • Female
  • Growth Plate / diagnostic imaging
  • Humans
  • Lumbar Vertebrae / diagnostic imaging*
  • Male
  • Osteogenesis Imperfecta / diagnostic imaging
  • Osteogenesis Imperfecta / drug therapy*
  • Treatment Outcome

Substances

  • Bone Density Conservation Agents
  • Diphosphonates
  • Denosumab