Association of Visceral and Subcutaneous Fat Mass With Bone Density and Vertebral Fractures in Women With Severe Obesity

Abstract

Introduction: The aim of this study was to evaluate the association of visceral and subcutaneous adipose tissue with bone mineral density (BMD), geometric indices of femoral neck strength and vertebral fractures in pre- and postmenopausal women with severe obesity.

Methods: A cross-sectional study was conducted with pre- (n = 37) and postmenopausal (n = 21) women with body mass index higher than 40 kg/cm². BMD at total body, lumbar spine, hip and forearm, presence of vertebral fractures, lean mass, visceral, and subcutaneous adipose tissue were assessed by DXA. Geometric indices of femoral neck strength were calculated by DXA. Serum bone turnover markers (CTX and osteocalcin) and 25(OH)D were also measured.

Results: BMD at all studied sites was similar in pre- and postmenopausal women. In postmenopausal women, total subcutaneous adipose tissue was inversely associated with BMD at total femur (β = -0.009; 95% confidence interval [CI] -0.017; -0.002) and with strength index (β = -0.03; 95% CI -0.04; -0.01). In premenopausal women, visceral adipose tissue was inversely associated with cross-sectional moment of inertia (β = -0.95; 95%CI -1.89; -0.01). Vertebral fractures were highly prevalent in premenopausal (32%), and even more frequent among postmenopausal women (55%).

Conclusion: Taken together, our results suggest that both visceral and subcutaneous fat may be detrimental for bone health in pre- and postmenopausal women, and that severe obesity may increase the risk of vertebral fractures, even in young women.

Keywords: Body composition; bone mineral density; bone turnover markers; geometric indices of hip strength; menopause; vertebral fracture.