IEEE J Biomed Health Inform. 2022 Jul;26(7):3409-3417. doi: 10.1109/JBHI.2022.3152538. Epub 2022 Jul 1.
Previous research showed that frailty can influence autonomic nervous system and consequently heart rate response to physical activities, which can ultimately influence the homeostatic state among older adults. While most studies have focused on resting state heart rate characteristics or heart rate monitoring without controlling for physical activities, the objective of the current study was to classify pre-frail/frail vs non-frail older adults using heart rate response to physical activity (heart rate dynamics). Eighty-eight older adults (≥65 years) were recruited and stratified into frailty groups based on the five-component Fried frailty phenotype. Groups consisted of 27 non-frail (age = 78.80±7.23) and 61 pre-frail/frail (age = 80.63±8.07) individuals. Participants performed a normal speed walking as the physical task, while heart rate was measured using a wearable electrocardiogram recorder. After creating heart rate time series, a long short-term memory model was used to classify participants into frailty groups. In 5-fold cross validation evaluation, the long short-term memory model could classify the two above-mentioned frailty classes with a sensitivity, specificity, F1-score, and accuracy of 83.0%, 80.0%, 87.0%, and 82.0%, respectively. These findings showed that heart rate dynamics classification using long short-term memory without any feature engineering may provide an accurate and objective marker for frailty screening.
先前的研究表明，虚弱会影响自主神经系统，进而影响老年人对身体活动的心率反应，这可能最终会影响他们的体内平衡状态。尽管大多数研究都集中在静息状态下的心率特征或心率监测上，而没有控制身体活动，但目前这项研究的目的是使用身体活动时的心率反应（心率动力学）来对虚弱的老年人进行分类（脆弱/虚弱与非脆弱）。研究招募了 88 名年龄在 65 岁及以上的老年人，并根据五个组成部分的弗莱德虚弱表型将他们分为虚弱组。组内包括 27 名非虚弱（年龄=78.80±7.23）和 61 名脆弱/虚弱（年龄=80.63±8.07）个体。参与者进行正常速度行走作为身体任务，同时使用可穿戴心电图记录器测量心率。在创建心率时间序列后，使用长短期记忆模型将参与者分为虚弱组。在 5 折交叉验证评估中，长短期记忆模型可以将上述两种脆弱类别分类，敏感性、特异性、F1 分数和准确率分别为 83.0%、80.0%、87.0%和 82.0%。这些发现表明，使用长短期记忆而无需任何特征工程的心率动力学分类可能为虚弱筛查提供准确、客观的标志物。
