Bone Marrow Adiposity and Fragility Fractures in Postmenopausal Women: The ADIMOS Case-Control Study.

Abstract

Noninvasive assessment of proton density fat fraction (PDFF) by MRI may improve the prediction of fractures. To determine if an association exists between PDFF and fractures. A case-control study with 2 groups of postmenopausal women: one with recent osteoporotic fractures, and the other with no fractures. Lille University Hospital, Lille, France. Lumbar spine and proximal femur (femoral head, neck, and diaphysis) PDFF, determined using chemical shift-based water-fat separation MRI (WFI) and DXA scans of the lumbar spine and hip. Our primary objective was to determine the relationship between lumbar spine PDFF and osteoporotic fractures in postmenopausal women. Analysis of covariance (ANCOVA) was used to compare PDFF measurements between cases (overall and according to the type of fracture) and controls, after adjusting for age, Charlson comorbidity index (CCI) and BMD. In 199 participants, controls (n = 99) were significantly younger (p < 0.001) and had significantly higher BMD (p < 0.001 for all sites) than cases (n = 100). 52 women with clinical vertebral fractures and 48 with nonvertebral fractures were included. When PDFFs in cases and controls were compared, after adjustment on age, CCI and BMD, no significant differences between the groups were found at lumbar spine or proximal femur. When PDFFs in participants with clinical vertebral fractures (n = 52) and controls were compared, femoral neck PDFF and femoral diaphysis PDFF were detected to be lower in participants with clinical vertebral fractures than in controls (adjusted mean (standard error) 79.3% (1.2) vs 83.0% (0.8), p = 0.020, and 77.7% (1.4) vs. 81.6% (0.9), p = 0.029, respectively). No difference in lumbar spine PDFF was found between those with osteoporotic fractures and controls. However, imaging-based proximal femur PDFF may discriminate between postmenopausal women with and without clinical vertebral fractures, independently of age, CCI and BMD.