Is Acute Exacerbation of Terminal Restlessness Predictable Using Continuous Monitoring with a Sheet-Type Nonwearable Sensor Device?

Abstract

Restlessness is a common and distressing symptom in terminally ill patients with cancer. It is often described as a sudden phenomenon near death; however, its longitudinal progression has not been well characterized. To examine whether terminal restlessness that worsens suddenly is preceded by changes detectable based on continuous monitoring using a sheet-type nonwearable sensor device. We conducted secondary analysis of a single-center prospective observational study in a Japanese palliative care unit (2019-2022). The severity of restlessness was measured as activity scores using a sheet-type nonwearable sensor device placed under the mattress. Group-based trajectory modeling was applied to night-time activity scores during the last 30 days of life. Richmond Agitation-Sedation Scale (RASS) scores and medication use were compared across trajectory groups. Of the 1,209 enrolled patients, 959 were included in the final analysis (median age: 75 years, 55% male). A specific patient cluster showing acute exacerbation of terminal restlessness just before death was identified (model-estimated group proportion, 11.1%). In this group, RASS scores and rates of using antipsychotics and benzodiazepines in the final days were significantly higher compared with those in the other groups. Activity scores did not show a sudden increase immediately prior to death; a gradual upward trend was observed beginning approximately two weeks before death, preceding the terminal rise. Approximately 10% of patients experienced exacerbation of terminal restlessness just before death. Continuous monitoring with a non-invasive sensor device may enable earlier detection and prevent exacerbation of terminal restlessness.