Unobtrusive Sensing Technology Detects Ecologically Valid Spatiotemporal Patterns of Daily Routines Distinctive to Persons with Mild Cognitive Impairment

Background The ability to capture people’s movement throughout their home is a powerful approach to inform spatiotemporal patterns of routines associated with cognitive impairment. The study estimated indoor room activities over 24 hours and investigated relationships between diurnal activity patterns and mild cognitive impairment (MCI). Methods 161 older adults (26 with MCI) living alone (age=78.9±9.2) were included from two study cohorts–the Oregon Center for Aging & Technology and the Minority Aging Research Study. Indoor room activities were measured by the number of trips made to rooms (bathroom, bedroom, kitchen, living room). Trips made to rooms (transitions) were detected using passive infrared motion sensors fixed on the walls for a month. Latent trajectory models were used to identify distinct diurnal patterns of room activities and characteristics associated with each trajectory. Results Latent trajectory models identified two diurnal patterns of bathroom usage (high; low usage). Participants with MCI were more likely to be in the high bathroom usage group that exhibited more trips to the bathroom than the low usage group (OR=4.1,95%CI [1.3-13.5],p=0.02). For kitchen activity, two diurnal patterns were identified (high; low activity). Participants with MCI were more likely to be in the high kitchen activity group that exhibited more transitions to the kitchen throughout the day and night than the low kitchen activity group (OR=3.2,95%CI [1.1-9.1],p=0.03). Conclusions The linkage between bathroom and kitchen activities with MCI may be the result of biological, health, and environmental factors in play. In-home, real-time unobtrusive-sensing offers a novel way of delineating cognitive health with chronologically-ordered movement across indoor locations.