A Markov Chain Model for Identifying Changes in Daily Activity Patterns of People Living With Dementia

Nan Fletcher-Lloyd, Alina-Irina Serban, Magdalena Anita Kolanko, David Wingfield, Danielle Wilson, Ramin Nilforooshan, Payam M. Barnaghi, Eyal Soreq

Abstract: Malnutrition and dehydration are strongly associated with increased cognitive and functional decline in people living with dementia (PLWD), as well as an increased rate of hospitalisations in comparison to their healthy counterparts. Extreme changes in eating and drinking behaviors can often lead to malnutrition and dehydration, accelerating the progression of cognitive and functional decline and resulting in a marked reduction in quality of life. Unfortunately, there are currently no established methods by which to objectively detect such changes. Here, we present the findings of an extensive quantitative analysis conducted on in-home monitoring data collected from 73 households of PLWD using Internet of Things technologies. The Coronavirus 2019 (COVID-19) pandemic has previously been shown to have dramatically altered the behavioral habits, particularly the eating and drinking habits, of PLWD. Using the COVID-19 pandemic as a natural experiment, we conducted linear mixed-effects modeling to examine changes in mean kitchen activity within a subset of 21 households of PLWD that were continuously monitored for 499 days. We report an observable increase in day-time kitchen activity and a significant decrease in night-time kitchen activity ( $t $ (147) $=\,\,-2.90 $ , ${p}$ < 0.001). We further propose a novel analytical approach to detecting changes in behaviors of PLWD using Markov modeling applied to remote monitoring data as a proxy for behaviors that cannot be directly measured. Together, these results pave the way to introduce improvements into the monitoring of PLWD in naturalistic settings and for shifting from reactive to proactive care.