Background: Almost 90% of people with dementia develop serious symptoms such as apathy, agitation, pain, and sleep disturbances. Movement and participation in daily activities also decrease dramatically over time. Traditional measures for these symptoms are usually in the form of a questionnaire and are not very accurate. Technology, such as a smartwatch, can be an effective tool for complementing traditional measures. Currently, there are few studies which look at activity and symptom measurements at the end-of-life. This makes results from this study extremely valuable for future care decisions, especially for people which may not be able to communicate their needs during the end-of-life period. Method/

Design: DIgital PHenotyping in DEMentia (DIPH.DEM), a 3-year cross-sectional observational study (N=50), will look at activities, apathy, agitation, and sleep disturbances using sensing technologies to monitor participants at the end of life. The objective of the study is to use a smartwatch and wireless radar (bedside) device (Somnofy), in addition to validated assessment tools to describe the activity patterns for patients with dementia at the end of life (baseline and every 6.months). We hypothesize that this will enable better estimation of time of death, facilitating discussion surrounding improvement of end-of-life interventions and directives. Discussion: The use of sensors (smartwatch and wireless beside device) can provide valuable knowledge on living and dying with dementia, improve end-of-life directives, and provide guidance for timely, appropriate interventions, including referral to palliative services. Impact on society: DIPH.DEM has the potential to enable more timely, precise, and quality care for people with dementia living at home, in nursing homes, and hospitals.