The Study of Muscle, Mobility and Aging with Knee OA

项目摘要/摘要 随着年龄的增长，肌肉骨骼组织的退化会导致骨关节炎、活动度降低和增加 残疾。骨关节炎(OA)经常影响膝盖，是世界范围内导致残疾的主要原因。穷 肌肉特征与膝关节骨性关节炎(KOA)和健康人的横断面比较有关 对照组和膝关节骨性关节炎受试者在肌肉成分、股四头肌肌力和力量方面表现出差异。一个 很少有小规模的横断面研究也严格地研究了与肌肉质量下降有关的 独立于膝关节骨性关节炎的老年人的活动能力，据报道肌肉质量减少，产生 三磷酸腺苷、失神经、氧化损伤和自噬减少。然而，这些临床研究一直是 小，只有横断面的，通常不包括有固定活动或有记录的膝骨性关节炎风险的个人。多么 这些肌肉质量随膝关节骨性关节炎的变化尚不清楚，这是理解减少的障碍 KOA中的行动不便和残疾增加。NIA/NIH最近资助了一项关于肌肉、活动能力和衰老的研究 (Somma)，刚刚开始招收875名中等功能、种族多样的年龄段的女性和男性 &gt；=70年。在两个中心。Somma研究的目的是：1)了解骨骼肌质量的贡献， 能量学，以及肌肉组织的关键特性，从活组织检查到严重的静止和残疾；以及2)产生 独一无二的肌肉组织、血液、基因表达数据和临床表型数据库，供 科学界。我们建议在第一次Somma后续访问时获得膝关节X光片，以了解 骨骼肌质量和组成对膝关节骨性关节炎患者活动能力降低和残疾的影响 受试者，如果这与没有KOA的受试者不同。具体目标是：目标1.比较基线 接受与不接受放射检查的个体的肌肉特性(肌肉力量、力量、成分、最大ATPmax) 膝关节骨性关节炎和无症状性膝关节骨性关节炎(放射学膝关节骨性关节炎和疼痛)。我们将检验这一假设 这些肌肉特性在有放射学和症状性膝骨性关节炎的受试者中有所不同 无膝关节骨性关节炎患者(有无疼痛)。目的2.确定放射学上的膝骨性关节炎和有症状 KOA与功能结果相关(400米步行速度和活动能力评估工具-缩写， MAT-SF功能障碍)与肌肉特性(肌肉力量、力量和成分、ATPmax)无关。 我们将检验这样一种假设，即患有放射学膝骨性关节炎和有症状的膝骨性关节炎患者的病情会更差。 独立于肌肉特征的功能结果。目标3.比较肌肉的关联性 特征(成分、力量、力量、最大ATPmax)和功能结果(400米步行速度和 MAT-SF残疾)在有和没有膝关节骨性关节炎以及有和没有症状的膝关节骨性关节炎的受试者中。我们将测试 假设肌肉特征与功能结果的关联在患有以下疾病的受试者中不同， 无放射学膝骨性关节炎，有无症状性膝骨性关节炎。

PROJECT SUMMARY / ABSTRACT Deterioration of musculoskeletal tissues with age results in osteoarthritis, reduced mobility, and increased disability. Osteoarthritis (OA) frequently affects the knee and is the leading cause of disability worldwide. Poor muscle characteristics are associated with knee OA (KOA) and cross-sectional comparisons of healthy controls and KOA subjects show differences in muscle composition, quadriceps muscle strength and power. A few, small cross-sectional studies have also rigorously investigated muscle qualities associated with reduced mobility in older adults, independent of KOA, and reported reduced muscle mass, decreased ability to generate ATP, denervation, oxidative damage, and decreased autophagy. However, these clinical studies have been small, only cross-sectional, and often did not include individuals at risk for immobility or documented KOA. How these muscle qualities change with KOA is not known and represents a roadblock to understanding reduced mobility and increased disability in KOA. The NIA/NIH recently funded a Study of Muscle, Mobility and Aging (SOMMA), which just began enrolling 875 intermediate functioning, ethnically diverse women and men age >=70yrs. at two centers. The SOMMA study aims to 1) understand the contributions of skeletal muscle mass, energetics, and key properties of muscle tissue from biopsies to major immobility and disability; and 2) produce a unique bank of muscle tissue, blood, gene expression data, and clinical phenotyping to be used by the scientific community. We propose to obtain knee radiographs at the first SOMMA follow-up visit to understand the contributions of skeletal muscle mass and composition that leads to reduced mobility and disability in KOA subjects and if this differs from subjects without KOA. The Specific Aims are: Aim 1. Compare the baseline muscle properties (muscle strength, power, composition, ATPmax) in individuals with vs. without radiographic KOA, and with vs. without symptomatic KOA (radiographic KOA and pain). We will test the hypothesis that these muscle properties differ in subjects with radiographic KOA and symptomatic KOA compared to individuals without KOA (with and without pain). Aim 2. Determine whether radiographic KOA and symptomatic KOA are associated with functional outcomes (400m walking speed and Mobility Assessment Tool- short form, MAT-sf Disabiilty) independently of muscle characteristics (muscle strength, power and composition, ATPmax). We will test the hypothesis that persons with radiographic KOA and symptomatic KOA will have worse functional outcomes independent of muscle characteristics. Aim 3. Compare the association of muscle characteristics (composition, strength, power, ATPmax) with functional outcomes (400m walking speed and MAT-sf disability) in subjects with and without KOA, and with and without symptomatic KOA. We will test the hypothesis that the association of muscle characteristics with functional outcomes is different in subjects with, and without radiographic KOA and with and without symptomatic KOA.