Akl Ahmad, Snoek Jasper, Mihailidis Alex
Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
Harvard School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
IEEE J Biomed Health Inform. 2017 Mar;21(2):339-348. doi: 10.1109/JBHI.2015.2512273. Epub 2015 Dec 24.
The early detection of dementias such as Alzheimer's disease can in some cases reverse, stop, or slow cognitive decline and in general greatly reduce the burden of care. This is of increasing significance as demographic studies are warning of an aging population in North America and worldwide. Various smart homes and systems have been developed to detect cognitive decline through continuous monitoring of high risk individuals. However, the majority of these smart homes and systems use a number of predefined heuristics to detect changes in cognition, which has been demonstrated to focus on the idiosyncratic nuances of the individual subjects, and thus, does not generalize. In this paper, we address this problem by building generalized linear models of home activity of older adults monitored using unobtrusive sensing technologies. We use inhomogenous Poisson processes to model the presence of the recruited older adults within different rooms throughout the day. We employ an information theoretic approach to compare the generalized linear models learned, and we observe significant statistical differences between the cognitively intact and impaired older adults. Using a simple thresholding approach, we were able to detect mild cognitive impairment in older adults with an average area under the ROC curve of 0.716 and an average area under the precision-recall curve of 0.706 using activity models estimated over a time window of 12 weeks.
诸如阿尔茨海默病等痴呆症的早期检测在某些情况下可以逆转、阻止或减缓认知衰退,总体上还能大大减轻护理负担。鉴于人口统计学研究警示北美及全球人口老龄化问题,这一点愈发重要。人们已开发出各种智能家居和系统,通过持续监测高危个体来检测认知衰退。然而,这些智能家居和系统大多使用一些预定义的启发式方法来检测认知变化,事实证明这种方法关注的是个体受试者特有的细微差别,因而缺乏通用性。在本文中,我们通过对使用非侵入式传感技术监测的老年人家庭活动建立广义线性模型来解决这一问题。我们使用非齐次泊松过程对全天不同房间内被招募老年人的出现情况进行建模。我们采用信息论方法比较所学习的广义线性模型,并且观察到认知功能正常和受损的老年人之间存在显著的统计差异。使用一种简单的阈值方法,通过在12周时间窗口内估计的活动模型,我们能够检测出老年人的轻度认知障碍,受试者工作特征曲线下平均面积为0.716,精确率-召回率曲线下平均面积为0.706。