The relationship between body composition and fracture risk using the FRAX model in central south Chinese...

To assess the relationship between body composition and fracture risk as determined by the FRAX(®) model in postmenopausal women in central south China.

A cross-sectional study was conducted in 779 women. Bone mineral density (BMD) of the left femur and total body composition were measured by dual X-ray absorptiometry. All clinical information was available for incorporation into the FRAX model to assess the 10-year fracture probability.

In the FRAX model, when BMD values were included, the 10-year probability of major osteoporotic fractures and hip fractures was 3·4% and 1·0%, respectively, which was significantly higher than the probability rates of 2·7% and 0·8%, respectively, for the same events when BMD values were not included (P < 0·01). Both fat mass and lean mass were negatively correlated with the predicted 10-year probability of fracture (P < 0·01), and femoral neck BMD was the most significant determinant of the predicted 10-year fracture probability. Compared with fat mass, lean mass had more impact on the 10-year probability of both major and hip osteoporotic fractures.

In postmenopausal women in central south China, both fat mass and lean mass were negatively correlated with the predicted 10-year fracture probability. The effect of lean mass and fat mass on fracture risk may be mediated through their impact on BMD. Compared with fat mass, lean mass had more of an impact on the risk of both major osteoporotic and hip fractures, showing that physical activity is an important component in the prevention of osteoporotic fracture.