Trabecular Bone Score And Bone Mineral Density In Older Adults

Abstract

The Trabecular Bone Score (TBS) is an estimate of the healthiness of bone microarchitecture that is based on the mathematical reconstruction of 3D micro-computed tomography (μCT) scans using 2D Dual-energy X-ray Absorptiometry (DXA). Compared to bone mineral density (BMD), TBS is a relatively new DXA-derived metric for predicting fracture risk. PURPOSE: This study examined the associations between classically measured vertebral bone mineral density (BMD) and TBS in inactive older adults. METHODS: For the present analyses, we included pre-training data from 19 older adults (X±SD; 71±4.2y, 4 black, 6 males) participating in an ongoing exercise intervention (REALPA). Whole-body and lumbar spine scans were acquired using a Hologic Horizon®A DXA scanner to determine BMD. TBS iNsight™ was used to determine the TBS score from lumbar spine DXA scans. Multivariate analyses were used to determine associations between whole-body and lumbar spine BMD with TBS scores, and sex differences were assessed by t-tests. RESULTS: A strong correlation between both whole-body BMD and lumbar spine TBS (r=0.815, p<0.0001) was observed; this was also true for lumbar spine BMD and lumbar spine TBS (r=0.834, p<0.0001). Sex differences were found (males vs. females) for Whole-body BMD (g/cm2; 1.156±0.12 vs 0.972±0.10, p<0.009), lumbar spine BMD (1.150±0.20 vs 0.920±0.15, p<0.05), and lumbar spine TBS (1.409±0.10 vs 1.285±.09, p<0.05). CONCLUSION: The sex differences for BMD and TBS are consistent with the literature, with males having higher BMD and TBS. Strong correlations between BMD and TBS suggest that TBS bone has construct validity. However, future studies are still warranted to determine whether TBS scoring provides clinically meaningful insight into fracture risk beyond traditional BMD. Furthermore, future research studies are warranted to determine whether exercise induced changes TBS are sensitive markers for exercise induced bone remodeling, which would provide additional insight into the clinical utility of TBS. This study was supported by the NIH 5R21AG058181-02.