Bone Abstracts

Objectives: To investigate the impact of Type 1 Diabetes Mellitus (T1DM) on cortical and trabecular microarchitecture, and bone strength in adolescents; using High Resolution peripheral Quantitative Computed Tomography (HRpQCT) and microfinite element analysis. To our knowledge, this is the first study in children, assessing the impact of T1DM on skeletal microstructure and strength using HRpQCT.

Methods: We recruited 22 patients aged 12–16 years with T1DM who were matched by age and gender with healthy controls. Recruits underwent a standard medical and fracture history; and diabetic therapy and control was assessed in T1DM patients. Participants then underwent DXA and HRpQCT scans. Paired t-tests were applied to assess differences in total body, lumbar and pelvic DXA parameters, cortical and trabecular microstructural parameters and skeletal strength. Regression analysis was used to determine if there was an association between HbA1C and duration of diabetes with changes in cortical and trabecular microarchitecture, and bone strength.

Results: There was no significant difference in the total body, lumbar spine and pelvic bone mineral density. Tibial trabecular thickness was lower in T1DM patients (−0.005 mm; CI −0.01, −0.001, P=0.029). There was a reduction in trabecular loading at the distal radius (Tb.F/TF distal: −6.2; CI −12.4, −0.03, P=0.049),and distal and proximal tibia (Tb.F/TF distal: −5.2; CI −9.2, −1.2, P=0.013), (Tb.F/TF proximal: −5.0; CI −9.8, −0.1, P=0.047). Regression models demonstrated a reduction in tibial stiffness (−0.877 kN.mm, P=0.03) and tibial failure load (−0.044 kN, P=0.03) with higher HbA1C before and after adjusting for age and gender.

Conclusion: Alteration of tibial trabecular microarchitecture is associated with an alteration in tibial loading properties. Similar loading alterations at the radius also appear to emerge in children with T1DM. Poor diabetic control may contribute to reduced tibial bone strength. Larger patient cohorts are required to determine if T1DM results in changes in skeletal integrity driven by duration and control of T1DM in childhood.

Disclosure: This study was funded by Sir Halley Stewart Trust and Internis Pharmaceuticals.