Sarcopenia, osteoporosis and the burden of prevalent vertebral fractures: a cross-sectional study of 350 women with hip fracture

BACKGROUND: The concurrent presence of sarcopenia and osteoporosis may enhance fracture risk. AIM: The aim of this study was to evaluate the association between sarcopenia, osteoporosis. or the concurrent presence of both the conditions (osteosarcopenia) and the burden (number and severity) of vertebral fractures in women with hip fracture. DESIGN: Cross-sectional study. SETTING: Division of Physical and Rehabilitation Medicine. POPULATION: We studied 350 women with subacute hip fracture. METHODS: Lateral radiographs of the spine were taken 18.2 +/- 4.5 days after fracture occurrence and the Spine Deformity Index (SDI) was calculated. Body composition was assessed by dual-energy X-ray absorptiometry. Low muscle mass was identified with appendicular lean mass <15.02 kg and low bone mineral density with a femoral T-Score <-2.5. RESULTS: The presence of sarcopenia (P=.033) and osteoporosis (P=.032) was associated with the SDI scores independently of each other and independently of age, percentage of body fat and hip-fracture type. The 350 women were categorized into 3 groups according to the absence of both osteoporosis and sarcopenia (N.=25)., presence of either osteoporosis or sarcopenia (N.=95) or presence of osteosarcopenia (N.=230). We found a significant difference in SDI scores across the 3 groups: chi(2) (2, N.=350) = 15.29; P<0.001. The categorization of the 350 women into the 3 groups was associated with the SDI scores (P=0.001) independently of age, percentage of body fat and hip-fracture type. CONCLUSIONS: Both osteoporosis and sarcopenia were independently associated with the burden of prevalent vertebral fractures in women with hip fracture. The concurrent presence of sarcopenia and osteoporosis was associated with a higher SDI Score than the presence of only one of the 2 conditions. CLINICAL REHABILITATION IMPACT: Subjects with both low bone mass and low muscle mass should be considered at particularly high risk for vertebral fractures. Interventions targeting both the components of the muscle-bone unit, including exercise, nutrition, and possibly new medications, should be investigated to optimize fracture prevention.