Block V J, Lizée A, Crabtree-Hartman E, Bevan C J, Graves J S, Bove R, Green A J, Nourbakhsh B, Tremblay M, Gourraud P-A, Ng M Y, Pletcher M J, Olgin J E, Marcus G M, Allen D D, Cree B A C, Gelfand J M
Department of Physical Therapy and Rehabilitation, University of California, San Francisco and San Francisco State University, San Francisco, CA, USA.
Department of Neurology, University of California San Francisco, 675 Nelson Rising Lane, Box 3206, San Francisco, CA, 94158, USA.
J Neurol. 2017 Feb;264(2):316-326. doi: 10.1007/s00415-016-8334-6. Epub 2016 Nov 28.
Disability measures in multiple sclerosis (MS) rely heavily on ambulatory function, and current metrics fail to capture potentially important variability in walking behavior. We sought to determine whether remote step count monitoring using a consumer-friendly accelerometer (Fitbit Flex) can enhance MS disability assessment. 99 adults with relapsing or progressive MS able to walk ≥2-min were prospectively recruited. At 4 weeks, study retention was 97% and median Fitbit use was 97% of days. Substudy validation resulted in high interclass correlations between Fitbit, ActiGraph and manual step count tally during a 2-minute walk test, and between Fitbit and ActiGraph (ICC = 0.76) during 7-day home monitoring. Over 4 weeks of continuous monitoring, daily steps were lower in progressive versus relapsing MS (mean difference 2546 steps, p < 0.01). Lower average daily step count was associated with greater disability on the Expanded Disability Status Scale (EDSS) (p < 0.001). Within each EDSS category, substantial variability in step count was apparent (i.e., EDSS = 6.0 range 1097-7152). Step count demonstrated moderate-strong correlations with other walking measures. Lower average daily step count is associated with greater MS disability and captures important variability in real-world walking activity otherwise masked by standard disability scales, including the EDSS. These results support remote step count monitoring as an exploratory outcome in MS trials.
多发性硬化症（MS）的残疾评估严重依赖于行走功能，而目前的指标未能捕捉到行走行为中潜在的重要变异性。我们试图确定使用方便消费者的加速度计（Fitbit Flex）进行远程步数监测是否能增强MS残疾评估。前瞻性招募了99名能够行走≥2分钟的复发型或进展型MS成年患者。在4周时，研究保留率为97%，Fitbit的中位使用天数为97%。子研究验证显示，在2分钟步行测试期间，Fitbit、ActiGraph与手动步数统计之间以及在7天家庭监测期间Fitbit与ActiGraph之间具有高度组内相关性（ICC = 0.76）。在连续4周的监测中，进展型MS患者的每日步数低于复发型MS患者（平均差异2546步，p < 0.01）。较低的平均每日步数与扩展残疾状态量表（EDSS）上更严重的残疾相关（p < 0.001）。在每个EDSS类别中，步数的显著变异性很明显（即EDSS = 6.0时，范围为1097 - 7152）。步数与其他行走测量指标显示出中度至高度的相关性。较低的平均每日步数与更严重的MS残疾相关，并捕捉到了现实世界中行走活动的重要变异性，而这些变异性在包括EDSS在内的标准残疾量表中被掩盖了。这些结果支持将远程步数监测作为MS试验中的一项探索性结果。
