Saturated and unsaturated bone marrow lipids have distinct effects on bone density and fracture risk in older adults
Journal of Bone and Mineral Research — Woods GN, Ewing SK, Schafer AL, et al. | January 19, 2022
Findings demonstrate worse skeletal outcomes in relation to saturated marrow lipids, while better outcomes in relation to unsaturated lipids, in general.
As greater bone marrow adiposity (BMAT) is related to lower bone mineral density (BMD) and vertebral fractures, this analysis of 465 participants from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study was conducted to study BMAT composition and bone outcomes.
Using magnetic resonance spectroscopy, BMAT saturation and unsaturation were defined as the ratio of saturated (1.3 ppm peak) or unsaturated (5.3 ppm peak) lipid to total marrow contents, respectively.
Each SD increase in BMAT saturation was found to be linked with lower trabecular BMD: -23.6% (spine), -13.0% (total hip).
Conversely, higher trabecular BMD: +17.5% (spine), +11.5% (total hip) were reported in relation to BMAT unsaturation (per SD increase).
A greater risk for prevalent [OR = 1.46] and incident [OR = 1.55] vertebral fracture was observed in relation to BMAT saturation (per SD increase).
BMAT unsaturation (per SD increase) was identified to be linked with lower risk for incident vertebral fracture [OR = 0.58].
In gender stratified studies, BMAT saturation and unsaturation were found to have opposite links with incident clinical fracture in men.