Bone microstructure and TBS in diabetes: what have we learned? A narrative review.

Abstract

Diabetes is associated with an increased risk of fracture. Areal bone mineral density (aBMD), the most reliable indicator of fracture risk in healthy adults, is low in patients with type 1 diabetes mellitus but normal or high in patients with type 2 diabetes mellitus. Most trabecular and cortical parameters measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) are lower in type 1 diabetes and higher in type 2 diabetes, in parallel with aBMD. In contrast, lumbar spine trabecular bone score (TBS) has been reported to be lower in women with both type 1 and type 2 diabetes. The discordance between improved bone microstructure and degraded TBS reflects the effect of central obesity (currently the subject of a revision to the TBS algorithm). Meanwhile, evidence supports use of TBS in conjunction with aBMD and/or FRAX for improved fracture prediction in patients with type T2D. This position paper, on behalf of the Bone and Diabetes Working Group of the International Osteoporosis Foundation, summarizes alterations in bone microarchitecture measured by HR-pQCT in diabetes. It also addresses the technical and clinical considerations of the trabecular bone score, particularly discussing the significance of this measurement in individuals with diabetes and the influence of abdominal fat.