Creation of the Age-Related TBS curve at Lumbar Spine in US Caucasian Women Derived from DXA

Type 2 diabetes mellitus (T2DM) is associated with fracture risk but, paradoxically, greater bone mineral density (BMD). The trabecular bone score (TBS) has been proposed as an index of bone microarchitecture associated with bone quality. This study compared the performance of TBS, BMD, and original and TBS-adjusted Fracture Risk Assessment Tool (FRAX®) scores in the discrimination of vertebral fractures (VFs) in T2DM patients. This retrospective study enrolled 169 Korean postmenopausal women with T2DM. Lateral plain radiographs of the thoracolumbar spine were taken. Lumbar spine and femur neck BMDs were obtained using dual-energy X-ray absorptiometry (DXA). TBS was obtained using the TBS iNsight software program (Med-Imaps, Pessac, France) with BMD DXA images (L1–L4). VFs were diagnosed when at least 1 of the 3 height measurements was decreased by >25% compared to the nearest uncompressed vertebral body. Among the subjects, 34 women (20.1%) had VFs. Significantly lower TBS (p = 0.008) and higher TBS-adjusted FRAX scores were shown (p = 0.019) in the group with VFs compared to the group without VFs. In contrast, there were no significant differences in BMD and original FRAX scores between the 2 groups. Odds ratios (ORs) per standard deviation decrease in BMD or TBS and per standard deviation increase in the FRAX score were estimated with adjustment for age. TBS (OR = 1.8, 95% confidence interval [CI]: 1.1–2.7, p = 0.011) and TBS-adjusted FRAX score (OR = 2.0, 95% confidence interval: 1.1–3.5, p = 0.020) showed statistically significant ORs but the others did not. TBS and TBS-adjusted FRAX could be supplementary tools to discriminate osteoporotic fractures in T2DM.