An interpretable machine learning tool for in-home monitoring of agitation episodes in people living with dementia: a proof-of-concept study

Background Agitation affects around 30% of people living with dementia (PLwD), increasing carer burden and straining care services. Agitation identification typically relies on subjective clinical scales and direct patient observation, which are resource-intensive and challenging to incorporate into routine care. Clinical applicability of data- driven methods for agitation monitoring is limited by constraints such as short observational periods, data granularity, and lack of interpretability and generalisation. Current interventions for agitation are primarily medication-based, which may lead to severe side effects and lack personalisation. Understanding how real-world factors interact with agitation within home settings offers a promising avenue towards identifying potential personalised non-pharmacological interventions. Methods We used longitudinal data (32,896 person-days from n = 63 PLwD) collected using in-home monitoring devices between December 2020 and March 2023. Employing machine learning techniques, we developed a monitoring tool to identify the presence of agitation during the week. We incorporated a traffic-light system to stratify agitation probability estimates supporting clinical decision-making, and employed the SHapley Additive exPlanations (SHAP) framework to enhance interpretability. We designed an interactive tool that enables the exploration of personalised non-pharmacological interventions, such as modifying ambient light and temperature. Findings Light Gradient-boosting Machine (LightGBM) achieved the highest performance in identifying agitation over an 8-day period with a sensitivity of 71.32% +/- 7.38 and specificity of 75.28% +/- 7.38. Implementing the traffic-light system for stratification increased specificity to 90.3% +/- 7.55 and improved all metrics. Key features for identifying agitation included low nocturnal respiratory rate, heightened alertness during sleep, and increased indoor illuminance, as revealed by statistical and feature importance analysis. Using our interactive tool, we identified indoor lighting and temperature adjustments as the most promising and feasible intervention options within our cohort. Interpretation Our interpretable framework for agitation monitoring, developed using data from a dementia care study, showcases significant clinical value. The accompanying interactive interface allows for the in-silico simulation of non-pharmacological interventions, facilitating the design of personalised interventions that can improve in-home dementia care.