Gender- and Age-Associated Differences in Bone Marrow Adipose Tissue and Bone Marrow Fat Unsaturation Throughout the...

Area of Science:

• Biomedical Imaging
• Skeletal Biology
• Adipose Tissue Research

Background:

• Bone marrow adipose tissue (BMAT) is metabolically active and linked to bone health and diseases like osteoporosis and cancer.
• Understanding BMAT's regional, age, and gender variations is crucial for interpreting its role in skeletal pathophysiology.

Purpose of the Study:

• To investigate region-specific variations in BMAT quantity and composition across the human skeleton.
• To determine age- and gender-specific differences in BMAT distribution and characteristics.

Main Methods:

• Cross-sectional study of 40 healthy subjects (26 male, 14 female).
• Utilized chemical shift encoding-based water-fat imaging (WFI) with multiple gradient echoes (mGRE).
• Quantified bone marrow fat fraction and unsaturation in the spine, pelvis, femora, and tibiae.

Main Results:

• BMAT fat fraction increased caudally in the spine and femur, but decreased caudally in the tibia.
• Age significantly correlated with spinal and pelvic BMAT fat fraction in females, and spinal BMAT in males.
• BMAT unsaturation showed distinct associations with fat fraction: negative in the spine, positive in extremities, independent of age and gender.

Conclusions:

• BMAT exhibits distinct, age- and gender-dependent distributions throughout the human skeleton.
• Human bone marrow unsaturation is highest in the axial skeleton, contrasting with animal studies.
• BMAT and its unsaturation have differing correlations within the axial versus appendicular skeleton.