National Institute on Aging, Translational Gerontology Branch , Baltimore, MD 21224, USA.
National Institute on Aging, Laboratory of Behavioral Neuroscience, Baltimore, MD 21224, USA.
Age Ageing. 2017 May 1;46(3):445-451. doi: 10.1093/ageing/afw185.
most older individuals who experience mobility decline, also show cognitive decline, but whether cognitive decline precedes or follows mobility limitation is not well understood.
examine the temporal sequence of mobility and cognition among initially unimpaired older adults.
mobility and cognition were assessed every 2 years for 6 years in 412 participants aged ≥60 with initially unimpaired cognition and gait speed. Using autoregressive models, accounting for the dependent variable from the prior assessment, baseline age, sex, body mass index and education, we examine the temporal sequence of change in mobility (6 m usual gait speed, 400 m fast walk time) and executive function (visuoperceptual speed: Digit Symbol Substitution Test (DSST); cognitive flexibility: Trail Making Test part B (TMT-B)) or memory (California Verbal Learning Test (CVLT) immediate, short-delay, long-delay).
there was a bidirectional relationship over time between slower usual gait speed and both poorer DSST and TMT-B scores (Bonferroni-corrected P < 0.005). In contrast, slower 400 m fast walk time predicted subsequent poorer DSST, TMT-B, CVLT immediate recall and CVLT short-delay scores (P < 0.005), while these measures did not predict subsequent 400 m fast walk time (P > 0.005).
among initially unimpaired older adults, the temporal relationship between usual gait speed and executive function is bidirectional, with each predicting change in the other, while poor fast walking performance predicts future executive function and memory changes but not vice versa. Challenging tasks like the 400 m walk appear superior to usual gait speed for predicting executive function and memory change in unimpaired older adults.
大多数经历行动能力下降的老年人也表现出认知能力下降，但认知能力下降是先于还是后于行动能力受限尚不清楚。
检查最初认知和行动能力无障碍的老年人中行动能力和认知能力的时间顺序。
412 名年龄≥60 岁、最初认知和步速无障碍的参与者，每 2 年评估一次，共 6 年，评估内容包括行动能力（6 米常速步行、400 米快走时间）和执行功能（视知觉速度：数字符号替代测验（Digit Symbol Substitution Test，DSST）；认知灵活性：连线测验 B 部分（Trail Making Test part B，TMT-B））或记忆（加利福尼亚语言学习测验（California Verbal Learning Test，CVLT）即时、短延迟、长延迟）。
常速步行速度较慢与 DSST 和 TMT-B 评分较差均呈双向关系（Bonferroni 校正 P < 0.005）。相比之下，400 米快走时间较慢预测随后的 DSST、TMT-B、CVLT 即时回忆和 CVLT 短延迟评分较差（P < 0.005），而这些措施不能预测随后的 400 米快走时间（P > 0.005）。
在最初认知无障碍的老年人中，常速步行速度与执行功能之间的时间关系是双向的，两者相互预测变化，而较差的快走表现预测未来的执行功能和记忆变化，但反之则不然。在认知无障碍的老年人中，400 米快走等具有挑战性的任务似乎优于常速步行速度，可用于预测执行功能和记忆变化。
