Adipose tissue and volumetric bone mineral density of older Afro-Caribbean men

Abstract

Although low body weight is a risk factor for osteoporosis-related fractures, conflicting data exist for the association between adiposity and bone mineral density (BMD). Studies examining these relationships have measured body fat and BMD with dual-energy X-ray absorptiometry (DXA), which cannot distinguish subcutaneous adipose tissue area (SAT) from total adiposity or trabecular from cortical bone. To investigate the relationship between adiposity and BMD further, we analyzed body composition and adipose tissue distribution by quantitative computed tomography (QCT) in 1829 Afro-Caribbean men aged 40 years and older from a population-based sample. Cortical volumetric BMD, muscle cross-sectional area, total adipose tissue area (TAT), and percentage SAT were measured at the proximal tibia. Trabecular volumetric BMD was measured at the distal tibia. We used analysis of covariance to test for associations between quartile of the adipose tissue measures and BMD, adjusting for anthropometric, health, and lifestyle factors. Higher TAT was associated with lower cortical BMD in both unadjusted and adjusted models ( p < .001). Men with a higher percentage SAT had greater cortical BMD ( p < .001). Similar associations were seen between percent SAT and trabecular BMD at the distal tibia. These results indicate that total adiposity is a potentially important correlate of bone mass in older men and that different fat depots may have opposing associations with bone mass. Additional research is needed to better understand the mechanisms underlying the relationship between body fat distribution and bone mass. ß

Skeletal muscle and pediatric bone development

“…Total body lean mass and muscle cross-sectional area (MCSA) are common surrogates of the muscular contractile forces of which bone is particularly responsive as muscle size and strength are closely related [6]. As a second example, pathogenic fat depots, for example, adiposity stored within the skeletal muscle, have piqued recent interest, as muscle fat in adults has been shown to be predictive of suboptimal bone outcomes and hip fracture [7,8].…”

Advances in Osteoimmunology: Pathophysiologic Concepts and Treatment Opportunities

“…Nevertheless, when the distribution of body fat is taken into consideration, the relation of fat and bone becomes complex: whereas subcutaneous fat appears to be beneficial to bone, visceral fat negatively affects bone density or bone strength indices [107,108,109]. Experimental data clearly demonstrate that high fat diet-induced obesity increases bone resorption and impairs trabecular microarchitecture [89,110].…”

Longitudinal relationships between whole body and central adiposity on weight-bearing bone geometry, density, and bone strength: a pQCT study in young girls

“…To our knowledge, no studies have assessed the longitudinal relationship between total and regional (abdominal) body fat and indices of bone strength from pQCT in peri-pubertal girls, a critical phase of bone development. Given that metabolic derangements associated with obesity are closely related with a central (abdominal) fat pattern [16], and because cross-sectional analyses have shown inverse associations between fat mass and bone strength in young girls [24] and adults [25], we hypothesized that higher levels of total body fat and android fat would be inversely associated with gains in bone strength at weight-bearing bone sites in young girls.…”