Kidney Week

Abstract: SA-PO654

Effect of Denosumab on Trabecular Bone Score (TBS) in De Novo Kidney Transplant Recipients (KTR)

Session Information

• Bone and Mineral Metabolism: Clinical - II
  October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 402 Bone and Mineral Metabolism: Clinical

Authors

• Wuthrich, Rudolf P., University Hospital, Zurich, ZH, Switzerland

Rudolf P. Wuthrich,

• Graf, Nicole, graf biostatistics, Winterthur, Switzerland

Nicole Graf,

• Bonani, Marco, University Hospital Zurich, Zurich, ZH, Switzerland

Marco Bonani,

Background

Kidney transplant recipients (KTR) are at high risk to lose bone mass in the first year after transplantation. The trabecular bone score (TBS) represents a recently developed parameter of lumbar spine bone texture that correlates with the occurrence of fractures. The utility of the TBS and its response to anti-resorptive treatment with denosumab in the first year after kidney transplantation is not known.

Methods

Post-hoc analysis of 1-year changes in TBS in 44 de novo KTR (mean age 50.6±12.6 years; 28 [64%] were male; mean baseline eGFR 54.1±16.5 ml/min/1.73 m²) which were randomized 1:1 to denosumab or no treatment, and correlation with 1-year areal bone mineral density (aBMD) changes at the lumbar spine and total hip as assessed by dual energy X-ray absorptiometry (DXA), and peripheral bone microarchitecture as assessed by high-resolution peripheral quantitative computed tomography (HRpQCT).

Results

The baseline TBS in KTR amounted to 1.312±0.101 which was reduced compared to an age-matched normal control population (1.464±0.071). There was a significant correlation between TBS and aBMD at the lumbar spine (Spearman’s ρ=0.56; p<0.001) and total hip (ρ=0.33; p<0.05). The TBS also correlated with HRpQCT-derived total (ρ=0.49; p<0.05) and trabecular volumetric BMD at the tibia (ρ=0.57; p<0.01), whereas no such correlation was found at the radius. Denosumab treatment led to an increase in TBS, paralleling the BMD changes at the lumbar spine. More denosumab-treated than control KTR showed an increase in TBS at 6 months (91% vs. 55%; p<0.01) and 12 months (87% vs 71%; p=ns). TBS increased more in denosumab-treated than control KTR (+4.0% vs +1.5%) in the first 6 months, but changed little (-0.4% vs +0.6%) in the subsequent 6 months.

Conclusion

The TBS represents a valuable parameter which provides additional data on bone health in KTR. The increase in TBS in denosumab-treated de novo KTR suggests that denosumab may improve bone microarchitecture in KTR.

Funding

• Government Support - Non-U.S.