Zhou He, Sabbagh Marwan, Wyman Rachel, Liebsack Carolyn, Kunik Mark E, Najafi Bijan
Interdisciplinary Consortium on Advanced Motion Performance (iCAMP), Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX,, USA.
Gerontology. 2017;63(2):189-200. doi: 10.1159/000452309. Epub 2016 Nov 18.
Objective and time-effective tools are needed to identify motor-cognitive impairment and facilitate early intervention.
We examined the feasibility, accuracy, and reliability of an instrumented trail-making task (iTMT) using a wearable sensor to identify motor-cognitive impairment among older adults.
Thirty subjects (age = 82.2 + 6.1 years, body mass index = 25.7 + 4.8, female = 43.3%) in 3 age-matched groups, 11 healthy, 10 with amnestic mild cognitive impairment (aMCI), and 9 with Alzheimer disease (AD), were recruited. Subjects completed iTMT, using a wearable sensor attached to the leg, which translates the motion of the ankle into a human-machine interface. iTMT tests included reaching to 5 indexed circles on a computer screen by moving the ankle-joint while standing. iTMT was quantified by the time required to reach all circles in the correct sequence. Three iTMT tests were designed, including numbers (1-5) positioned in a fixed (iTMTfixed) or random (iTMTrandom) order, or numbers (1-3) and letters (A and B) positioned in random order (iTMTnumber-letter). Each test was repeated twice to examine test-retest reliability. In addition, the conventional trail-making task (TMT A and B), Montreal Cognitive Assessment (MoCA), and dual-task cost (DTC: gait-speed difference between walking alone and walking while counting backward) were used as references. Re sults: Good-to-excellent reliability was achieved for all iTMT tests (intraclass correlation [ICC] = 0.742-0.836). Between-group difference was more pronounced, when using iTMTnumber-letter, with average completion time of 26.3 ± 12.4, 37.8 ± 14.1, and 61.8 ± 34.1 s, respectively, for healthy, aMCI, and AD groups (p = 0.006). Pairwise comparison suggested strong effect sizes between AD and healthy (Cohen's d = 1.384, p = 0.001) and between aMCI and AD (d = 0.923, p = 0.028). Significant correlation was observed when comparing iTMTnumber-letter with MoCA (r = -0.598, p = 0.001), TMT A (r = 0.519, p = 0.006), TMT B (r = 0.666, p < 0.001), and DTC (r = 0.713, p < 0.001).
This study demonstrated proof of concept of a simple, safe, and practical iTMT system with promising results to identify cognitive and dual-task ability impairment among older adults, including those with aMCI and AD. Future studies need to confirm these observations in larger samples, as well as iTMT's ability to track motor-cognitive decline over time.
需要客观且高效的工具来识别运动认知障碍并促进早期干预。
我们使用可穿戴传感器检测了一种仪器化连线测试（iTMT）在识别老年人运动认知障碍方面的可行性、准确性和可靠性。
招募了30名受试者（年龄 = 82.2 ± 6.1岁，体重指数 = 25.7 ± 4.8，女性占43.3%），分为3个年龄匹配组，11名健康者，10名患有遗忘型轻度认知障碍（aMCI），9名患有阿尔茨海默病（AD）。受试者使用连接在腿部的可穿戴传感器完成iTMT，该传感器将踝关节的运动转换为人机界面。iTMT测试包括站立时通过移动踝关节在电脑屏幕上触及5个索引圆圈。iTMT通过按正确顺序触及所有圆圈所需的时间进行量化。设计了3项iTMT测试，包括数字（1 - 5）按固定顺序（iTMTfixed）或随机顺序（iTMTrandom）排列，或数字（1 - 3）和字母（A和B）按随机顺序排列（iTMTnumber - letter）。每项测试重复两次以检验重测信度。此外，使用传统连线测试（TMT A和B）、蒙特利尔认知评估（MoCA）以及双重任务成本（DTC：独自行走与倒着数数时行走的步态速度差异）作为对照。结果：所有iTMT测试均获得了良好至优秀的信度（组内相关系数[ICC] = 0.742 - 0.836）。使用iTMTnumber - letter时，组间差异更为明显，健康组、aMCI组和AD组的平均完成时间分别为26.3 ± 12.4秒、37.8 ± 14.1秒和61.8 ± 34.1秒（p = 0.006）。两两比较显示AD组与健康组之间（科恩d值 = 1.384，p = 0.001）以及aMCI组与AD组之间（d = 0.923，p = 0.028）效应量较大。将iTMTnumber - letter与MoCA（r = -0.598，p = 0.001）、TMT A（r = 0.519，p = 0.006）、TMT B（r = 0.666，p < 0.001）和DTC（r = 0.713，p < 0.001）进行比较时，观察到显著相关性。
本研究证明了一种简单、安全且实用的iTMT系统的概念验证，该系统在识别老年人（包括患有aMCI和AD的老年人）的认知和双重任务能力障碍方面取得了有前景的结果。未来的研究需要在更大样本中证实这些观察结果，以及iTMT随时间追踪运动认知衰退的能力。
