Hicks Gregory E, Simonsick Eleanor M, Harris Tamara B, Newman Anne B, Weiner Debra K, Nevitt Michael A, Tylavsky Frances A
Clinical Research Branch, National Institute on Aging, Baltimore, MD 21201, USA.
J Gerontol A Biol Sci Med Sci. 2005 Jul;60(7):882-7. doi: 10.1093/gerona/60.7.882.
Associations between trunk muscle composition and physical function have not been examined previously in older adults. We hypothesized that lower trunk muscle area and attenuation (higher fat infiltration) are associated with decreased functional capacity.
The study sample consisted of a biracial cohort of well functioning men (739) and women (788) aged 70-79 from the Pittsburgh site of the Health, Aging and Body Composition (Health ABC) study. Computed tomography was used to measure trunk muscle area (cm2) and muscle attenuation (Hounsfield Unit [HU]) of the following muscle groups: lumbar paraspinals, lateral abdominals, and rectus abdominis. An average score was calculated for both trunk area and attenuation. The Health ABC Physical Performance Battery (PPB) and its individual components (usual and narrow walk, chair stands, and standing balance) were used to measure functional capacity.
Linear regression analyses adjusting for demographic factors, height, body fat, thigh muscle composition, disease status, and low back pain (LBP) found that average trunk muscle area was not associated with any element of functional capacity (p >.10), whereas average trunk muscle attenuation was positively associated with the Health ABC Physical Performance Battery (p <.05) and chair stands (p <.001). Participants reporting higher LBP severity during the past year had lower muscle attenuation (p <.001 for trend), but there was no difference in average trunk muscle area according to LBP status.
Findings suggest a link between trunk muscle composition and history of LBP as well as reduced functional capacity in older adults. Improving trunk muscle quality may lead to reduced LBP severity and improved functional status.
此前尚未对老年人躯干肌肉组成与身体功能之间的关联进行过研究。我们假设较低的躯干肌肉面积和衰减（较高的脂肪浸润）与功能能力下降有关。
研究样本包括来自健康、衰老和身体成分（Health ABC）研究匹兹堡站点的739名功能良好的70 - 79岁男性和788名女性的双种族队列。使用计算机断层扫描测量以下肌肉群的躯干肌肉面积（平方厘米）和肌肉衰减（亨氏单位[HU]）：腰旁肌、腹外侧肌和腹直肌。计算躯干面积和衰减的平均得分。使用Health ABC身体性能测试组（PPB）及其各个组成部分（正常和窄幅行走、从椅子上站起以及站立平衡）来测量功能能力。
在对人口统计学因素、身高、体脂、大腿肌肉组成、疾病状态和腰痛（LBP）进行调整的线性回归分析中发现，平均躯干肌肉面积与功能能力的任何要素均无关联（p > 0.10），而平均躯干肌肉衰减与Health ABC身体性能测试组（p < 0.05）和从椅子上站起（p < 0.001）呈正相关。报告过去一年LBP严重程度较高的参与者肌肉衰减较低（趋势p < 0.001），但根据LBP状态，平均躯干肌肉面积没有差异。
研究结果表明老年人躯干肌肉组成与LBP病史以及功能能力下降之间存在联系。改善躯干肌肉质量可能会降低LBP严重程度并改善功能状态。
