Assessing bone impairment in ankylosing spondylitis (AS) using the trabecular bone score (TBS) and high-resolution peripheral quantitative computed tomography (HR-pQCT)

Author(s)

Caparbo, Valeria F. ^[1] ; Furlam, Pedro ^[1] ; Saad, Carla G. S. ^[1] ; Alvarenga, Jackeline C. ^[1] ; Aubry-Rozier, Berengere ^[2] ; Hans, Didier ^[2] ; de Brum-Fernandes, Artur J. ^[3] ; Pereira, Rosa M. R. ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Med, Hosp Clin HCFMUSP, Bone Metab Lab, Rheumatol Div, Sao Paulo, SP - Brazil

^[2] Lausanne Univ Hosp, Bone & Joint Dept, Rheumatol Div, Ctr Bone Dis, Lausanne - Switzerland

^[3] Univ Sherbrooke, Fac Med & Sci Sante, Serv Rhumatol, Dept Med, Sherbrooke, PQ - Canada

• Document type: Journal article
• Source: BONE; v. 122, p. 8-13, MAY 2019.
• Web of Science Citations: 0

Abstract

Objectives: To compare bone quality using the trabecular bone score (TBS) and bone microarchitecture in the distal tibia using high-resolution peripheral quantitative computed tomography (HR-pQCT) in ankylosing spondylitis (AS) patients and healthy controls (HC). Methods: Areal bone mineral density (aBMD) and TBS (TBS iNsight software) were evaluated using DXA (Hologic, QDR 4500); while volumetric bone mineral density (vBMD) and bone microarchitecture were analyzed in the distal tibia using HR-pQCT (Scanco) in 73 male patients with AS and 52 age-matched HC. Results: AS patients were a mean 41.6 +/- 7.9 years old and had a mean disease duration of 16.4 +/- 8.6 y, with a mean mSASSS 25.6 +/- 16.4. No difference was observed in lumbar spine aBMD in AS patients and HC (p = 0.112), but total hip BMD (p = 0.011) and TBS (p < 0.001) were lower in AS patients. In the distal tibia, reduced trabecular volumetric density {[}Tb.vBMD (p < 0.006)] and structural alterations - trabecular thickness (Tb.Th), p = 0.044 and trabecular separation (Tb.Sp), p = 0.039 - were observed in AS patients relative to controls. Further analysis comparing TBS < 1.310 and TBS >= 1.310 in AS patients revealed a higher mean body mass index {[}BMI] (p = 0.010), lower tibia cortical vBMD {[}Ct.vBMD] (p = 0.007), lower tibia cortical thickness {[}Ct.Th] : (p = 0.048) in the former group. On logistic regression analysis, BMI (OR = 1.27; 95%IC = 1.08-1.50, p = 0.005), (VF 4.65; 1.13-19.1, p = 0.033) and tibial Ct.vBMD (0.98; 0.97-1.00, p = 0.007) were associated with a lower TBS ( < 1.310). Conclusions: The present study demonstrates that TBS and HR-pQCT imaging are important technologies evaluating bone impairment in AS patients. Moreover, in these patients vertebral fractures were associated with lower TBS. (AU)

• FAPESP's process: 11/23781-2 - Role of osteoclastogenesis and osteoclasts activation in patients with ankylosing spondylitis
• Grantee: Rosa Maria Rodrigues Pereira
• Support Opportunities: Regular Research Grants