We investigated how baseline values and rates of decline in components of sarcopenia and other body composition parameters relate to adverse clinical outcomes using the Health, Aging, and Body Composition Study. 2689 participants aged 70–79 years were studied. Appendicular lean mass, whole body fat mass, and total hip BMD were ascertained using DXA; muscle strength by grip dynamometry; and muscle function by gait speed. Baseline values and 2–3 year conditional changes (independent of baseline) in each characteristic were examined as predictors of mortality, hospital admission, low trauma fracture, and recurrent falls in the subsequent 10–14 years using Cox regression (generalized estimating equations used for recurrent falls) with adjustment for sex, ethnicity, age, and potential confounders. Lower levels and greater declines in all parameters (excluding hip BMD level) were associated (p < 0.05) with increased rates of mortality; fully-adjusted hazard ratios per SD lower gait speed and grip strength were 1.27 (95% CI 1.19, 1.36) and 1.14 (1.07, 1.21), respectively. Risk factors of hospital admission included lower levels and greater declines in gait speed and grip strength, and greater declines in hip BMD. Lower levels and greater declines in fat mass and hip BMD were associated with low trauma fracture. Lower gait speed, higher fat mass, and both lower levels and greater declines in grip strength were related to recurrent falls. Lower baseline levels and greater declines in musculoskeletal parameters were related to adverse outcomes. Interventions to maximize peak levels in earlier life and reduce rates of age-related decline may reduce the burden of disease in this age group.

我们利用健康、衰老和身体成分研究，研究了肌少症成分和其他身体成分参数的基线值和下降率与不良临床结果的关系。对 2689 名 70-79 岁的参与者进行了研究。使用 DXA 确定四肢去脂质量、全身脂肪质量和总髋部 BMD；通过握力测力法测量肌肉力量；和步态速度的肌肉功能。使用 Cox 回归（广义估计方程反复跌倒），并根据性别、种族、年龄和潜在的混杂因素进行调整。所有参数（不包括髋部 BMD 水平）的较低水平和较大下降与死亡率增加相关（ p < 0.05）；完全调整后的每 SD 步速和握力降低的风险比分别为 1.27 (95% CI 1.19, 1.36) 和 1.14 (1.07, 1.21)。入院的危险因素包括步态速度和握力水平较低且下降幅度较大，以及髋部 BMD 下降幅度较大。脂肪量和髋部骨密度的较低水平和较大下降与低创伤性骨折相关。较低的步态速度、较高的脂肪量以及较低水平和较大的握力下降都与反复跌倒有关。较低的基线水平和肌肉骨骼参数的较大下降与不良后果有关。最大限度地提高生命早期峰值水平并降低与年龄相关的衰退率的干预措施可能会减轻该年龄段的疾病负担。