Session Information
Session Type: ACR Poster Session B
Session Time: 9:00AM-11:00AM
Background/Purpose: Ankylosing Spondylitis (AS) is a chronic inflammatory disease characterized by new bone growth that leads to syndesmophytes formation. However, AS patients present low bone mineral density (BMD) or osteoporosis that can be associated to systemic inflammation and decreased mobility. Low bone mass diagnosis in AS patients is based on data using dual-energy X-ray absorptiometry (DXA), which may present confusion factor for the presence of syndesmophytes and difficulty in patient positioning on the DXA table.Other limitation of DXA is that it cannot distinguish between bone compartments.Thus, the objective of this study is evaluate bone microarchitecture, cortical and trabecular, at spine and peripheral sites analyzing bone parameters using other images technology in AS patients. Patients and
Methods: Seventy-nine male patients with AS were evaluated compared with age-matched male controls. Demographic, anthropometric, disease duration, disease activity Score (BASDAI) and medication using were recorded. None patient was using bisphosphonates. Bone mineral density (BMD) was evaluated by using dual-energy X-ray absorptiometry (DXA-Hologic). Trabecular bone score (TBS iNsight software) was analyzed from lumbar spine measurement for vertebrae L1–L4 exactly at the same ROI as spine BMD DXA. Trabecular and cortical parameters were measured by High-resolution peripheral quantitative computed tomography (HR-pQCT- Scanco) at distal tibia.
Results: Patients with AS had a mean 42.6 ± 8.9 yrs and a mean disease duration of 17.4 ± 9.7 yrs. Bone mineral density at lumbar spine in AS patients showed higher values compared with control group (1.104 ± 0.206 vs 1.041 ± 0.117g/cm2, p = 0.023) and lower BMD at total hip (0.951 ± 0.015 vs. 1.003 ± 0.015 g/cm2, p= 0.017). Differently, TBS analysis showed lower values of this score in patients than control group (1.317 ± 0.121 vs. 1.396 ± 0.070, p <0.001). AS patients had lower values than controls of trabecular parameters as Tb.N (1.82 ± 0.34 vs. 1.94 ± 0.32, p=0.03), Tb.Th (0.07 ± 0.01 vs 0.08 ± 0.01, p= 0.008); cortical parameter as Ct.Th (1.24 ± 0.32 vs 1.36 ± 0.27, p=0.024) and total vBMD parameters (293.2 ± 67.69 vs. 319.15 ± 55.07, p= 0.019) at distal tibia measured by HR-pQCT. The bone strength parameters such as stiffness and stress estimated by finite element analysis were lower in AS patients than controls (p<0.001). In AS patients, TBS correlated negatively with mSASSS (r=-0.325; p=0.003). Furthermore, TBS correlated positively with trabecular thickness (Tb.Th) at tibia (r=0.228; p=0.047).
Conclusion: The TBS and HR-pQCT imaging measurements seems to be a good technologies to analysis the bone microarchitecture parameters in AS patients allowing better interpretation and possible predicting the fracture risk in these patients.
To cite this abstract in AMA style:
Caparbo VF, Saad CGS, Alvarenga JC, Pereira RMR. Evaluation of Spine and Tibia Bone Microarchitecture Using Trabecular Bone Score (TBS) and HR-pQCT in Patients with Ankylosing Spondylitis [abstract]. Arthritis Rheumatol. 2016; 68 (suppl 10). https://acrabstracts.org/abstract/evaluation-of-spine-and-tibia-bone-microarchitecture-using-trabecular-bone-score-tbs-and-hr-pqct-in-patients-with-ankylosing-spondylitis/. Accessed .« Back to 2016 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/evaluation-of-spine-and-tibia-bone-microarchitecture-using-trabecular-bone-score-tbs-and-hr-pqct-in-patients-with-ankylosing-spondylitis/