Sarcopenia and sarcopenic leg as potential risk factors for acute osteoporotic vertebral fracture among older women

Sarcopenia-related falls and fractures among women with osteoporosis are becoming an emerging problem because of rapid aging worldwide. We aimed to investigate the association between sarcopenia, given by the muscle mass of the arms and legs, and osteoporotic vertebral fracture (OVF) among female patients. This cross-sectional study examined 216 women with fresh OVF (OVF group) diagnosed by magnetic resonance imaging and 1,608 women from an outpatient clinic who did not have a OVF [non-fracture (NF) group]. We performed whole-body dual-energy X-ray absorptiometry to analyze body composition, including skeletal muscle mass index (SMI; lean mass/height(2)) and bone mineral density (BMD). We used stepwise logistic regression analysis to determine the risk factors associated with OVF. After controlling for age, the OVF group showed lower appendicular SMI (5.62 vs. 5.97 kg/m(2), P < 0.001), lower arm SMI (1.36 vs. 1.42 kg/m(2), P = 0.004), lower leg SMI (4.27 vs. 4.55 kg/m(2), P < 0.001), and higher prevalence of sarcopenia (42.3 vs. 25.9 %, P < 0.001), compared with the NF group. Reduced leg muscle mass and presence of sarcopenia were independent risk factors for acute OVF in multivariate analysis (odds ratio = 1.4, P = 0.002; odds ratio = 1.96, P < 0.001, respectively). We found higher prevalence of sarcopenia and lower leg muscle mass among patients with acute OVF compared with patients who did not have an OVF. These results suggest that sarcopenia may be a risk factor for OVF.