Body composition as an index of the trabecular bone score in postmenopausal women

Obesity is considered to exert a protective effect on bone mineral density (BMD). However, emerging data indicate that the effect of adipose tissue on bone health is much more complex. Trabecular bone score (TBS) provides information on bone texture and predicts fracture risk independently of BMD. This study investigated the association of body composition and bone quality as evaluated by lumbar spine (LS) TBS.

Cross-sectional study including 118 postmenopausal women (mean age 60.73 ± 8.97 years and mean BMI 28.36 ± 5.8) with no history of secondary osteoporosis or previous anti-osteoporotic treatment.

Body composition, BMD and LS TBS were evaluated by dual-energy X-ray absorptiometry (DXA). Τo explore the associations among the variables of interest, Spearman's correlations were used. Simple and multiple linear regression models were also applied to explore the associations among variables of interest.

Visceral adipose tissue (VAT) mass, android fat mass and android/gynoid fat ratio were negative predictors of TBS (Stb = -0.413, p < 0.001; Stb = -0.369, p < 0.001; Stb = -0.333, p < 0.001, respectively). Similarly, both the right (Stb = -0.313, p < 0.001) and left arm fat mass (Stb = -0.313, p < 0.001) were negative predictors of TBS. In a multiple linear regression model, VAT mass exhibited a significant negative association with TBS (Stb = -0.415, p < 0.05).

The present study offers evidence that VAT mass has a negative association with bone texture as estimated by TBS in postmenopausal women. Moreover, the findings suggest that the body composition of the arms (arm fat mass) correlates inversely with the bone texture. Further research is required to validate these findings in large cohorts of postmenopausal women.