Wong A K O, Cawthon P M, Peters K W, Cummings S R, Gordon C L, Sheu Y, Ensrud K, Petit M, Zmuda J M, Orwoll E, Cauley J
Department of Medicine, McMaster University, Hamilton, ON, Canada.
J Musculoskelet Neuronal Interact. 2014 Sep;14(3):246-54.
To assess bone-muscle (B-M) indices as risk factors for incident fractures in men.
Participants of the Osteoporotic Fractures in Men (MrOS) Study completed a peripheral quantitative computed tomography scan at 66% of their tibial length. Bone macrostructure, estimates of bone strength, and muscle area were computed. Areal bone mineral density (aBMD) and body composition were assessed with dual-energy X-ray absorptiometry. Four year incident non-spine and clinical vertebral fractures were ascertained. B-M indices were expressed as bone-to-muscle ratios for: strength, mass and area. Discriminative power and hazards ratios (HR) for fractures were reported.
In 1163 men (age: 77.2±5.2 years, body mass index (BMI): 28.0±4.0 kg/m(2), 4.1±0.9 follow-up years, 7.7% of men ⋝1 fracture), B-M indices were smaller in fractured men except for bending and areal indices. Smaller B-M indices were associated with increased fracture risk (HR: 1.30 to 1.74) independent of age and BMI. Strength and mass indices remained significant after accounting for lumbar spine but not total hip aBMD. However, aBMD correlated significantly with B-M indices.
Mass and bending B-M indices are risk factors for fractures in men, but may not improve fracture risk prediction beyond that provided by total hip aBMD.
评估骨-肌肉（B-M）指数作为男性发生骨折的风险因素。
男性骨质疏松性骨折（MrOS）研究的参与者在胫骨长度66%处完成外周定量计算机断层扫描。计算骨宏观结构、骨强度估计值和肌肉面积。用双能X线吸收法评估面积骨密度（aBMD）和身体成分。确定四年内发生的非脊柱和临床椎体骨折情况。B-M指数表示为强度、质量和面积的骨与肌肉比率。报告骨折的判别能力和风险比（HR）。
在1163名男性中（年龄：77.2±5.2岁，体重指数（BMI）：28.0±4.0kg/m²，随访4.1±0.9年，7.7%的男性发生≥1次骨折），除弯曲和面积指数外，骨折男性的B-M指数较小。较小的B-M指数与骨折风险增加相关（HR：1.30至1.74），且独立于年龄和BMI。在考虑腰椎但不考虑全髋aBMD后，强度和质量指数仍具有显著性。然而，aBMD与B-M指数显著相关。
质量和弯曲B-M指数是男性骨折的风险因素，但可能无法比全髋aBMD更好地改善骨折风险预测。
