Association between myosteatosis and bone mineral density in postmenopausal women
摘要
This study examined the association between abdominal muscle quality and bone mineral density (BMD) in 2021 postmenopausal women. A better muscle quality was associated with higher BMD and lower osteoporosis risk, independent of fat and muscle mass, highlighting the clinical relevance of muscle quality in bone health.
PurposeLoss of skeletal muscle and bone strength increases the risk of falls and fractures. The association between abdominal muscle quality—assessed by myosteatosis using computed tomography (CT)—and bone mineral density (BMD) remains unclear. We investigated this association in postmenopausal women who underwent abdominal CT during health check-ups.
MethodsThe total abdominal muscle area (TAMA), visceral fat area (VFA), subcutaneous fat area (SFA), and skeletal muscle area (SMA) at the third lumbar vertebral level were measured. SMA was classified into normal attenuation muscle area (NAMA) and low attenuation muscle area (LAMA). The NAMA/TAMA index, which reflects the proportion of higher-quality muscle, was calculated.
ResultsAmong 2021 women, 259 (12.8%) had osteoporosis. TAMA, SMA, NAMA (p < 0.001), and the NAMA/TAMA index (p = 0.012) were lower in the osteoporosis group. The prevalence of osteoporosis tended to decrease with increasing tertiles of the NAMA/TAMA index (15.3%, 12.2%, and 11.0%; p = 0.051). The prevalence of vertebral fractures decreased with increasing tertiles of the NAMA/TAMA index (p = 0.005). Lumbar spine, femoral neck, and total hip BMD increased significantly with higher NAMA/TAMA index tertiles after adjusting for confounders (p < 0.001, p = 0.011, and p < 0.001, respectively). The adjusted odds ratio (OR) for osteoporosis in the highest tertile was lower than in the lowest (OR = 0.58, 95% confidence interval = 0.38–0.87), even after adjusting for both abdominal fat and muscle area.
ConclusionPostmenopausal women with higher-quality abdominal muscles exhibited higher BMD at all sites and a lower prevalence of osteoporosis, independent of abdominal adiposity and total muscle mass.