A Contemporary View of the Diagnosis of Osteoporosis in Patients With Axial Spondyloarthritis

Abstract

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that primarily affects the axial joints. Altered bone metabolism associated with chronic inflammation leads to both new bone formation in the spine and increased bone loss. It is known that patients with axSpA have a high prevalence of osteoporosis and fractures. However, there is no consensus on which imaging modality is the most appropriate for diagnosing osteoporosis in axSpA. Bone mineral density measurement using dual-energy X-ray absorptiometry is the primary diagnostic method for osteoporosis, but it has notable limitations in patients with axSpA. This method may lead to the overestimation of bone density in patients with axSpA because they often exhibit abnormal calcification of spinal ligaments or syndesmophytes. Therefore, the method may not provide adequate information about bone microarchitecture. These limitations result in the underdiagnosis of osteoporosis. Recently, new imaging techniques, such as high-resolution peripheral quantitative computed tomography, and trabecular bone score have been introduced for the evaluation of osteoporosis risk in patients with axSpA. In this review, we summarize the current knowledge regarding imaging techniques for diagnosing osteoporosis in patients with axSpA.

Low-dose CT hounsfield units: a reliable methodology for assessing vertebral bone density in radiographic axial spondyloarthritis

“…3 4 The most appropriate and valid method to assess bone mineral density (BMD) in patients with r-axSpA is still unclear. 3 Dual-energy X-ray absorptiometry (DXA) is considered an accurate, repeatable and quantitative 2D method to assess BMD at the spine and hip, with a low dose up to less than 1 μSv. 5 Notwithstanding, new bone formation and aberrant…”

“…RMD Open RMD Open RMD Open hyperostosis may artificially increase BMD of the spine. 3 New imaging techniques for measuring BMD at the vertebral level have emerged in the past years. 6 Quantitative CT, a 3D technique, has been shown to estimate trabecular vertebral BMD avoiding the ectopic osteoproliferative changes.…”

Effects of Biological/Targeted Therapies on Bone Mineral Density in Inflammatory Arthritis

“…Pathological bone formation is one of the most iconic hallmarks of spondyloarthritis (SpA), including axial-SpA and psoriatic arthritis (PsA) [94]. In patients suffering from long-term axial-SpA, bone formations that manifest as entheseal bone formation, periostitis, and spinal syndesmophytes are strongly correlated with the burden of the disease and resulting disability [94]. The adverse effects caused by bone losses in spondyloarthritis may impair the patients' quality of life and activities of daily living [94].…”

“…In patients suffering from long-term axial-SpA, bone formations that manifest as entheseal bone formation, periostitis, and spinal syndesmophytes are strongly correlated with the burden of the disease and resulting disability [94]. The adverse effects caused by bone losses in spondyloarthritis may impair the patients' quality of life and activities of daily living [94]. Previous observational studies have evaluated the association between SpA and osteopenia or osteoporosis, with conflicting results [95].…”

“…Psoriatic patients had lower volumetric BMD than non-psoriatic controls. On the other hand, osteoporosis is a frequent complication in patients with ankylosing spondylitis (AS) [94]. Low BMD, osteoporosis, and fractures are reported to be associated with AS [98].…”