Psychological Stress Detection in Older Adults with Cognitive Impairment Using Photoplethysmography

Psychological stress can have significant impacts on both physical and mental health. Chronic stress brings multiple adverse health outcomes, including cognitive difficulties. Unfortunately, there is a dearth of literature on the use of physiological sensor data to detect stress and analysis on the effects of gender and cognitive impairment on stress response in older adults, an especially important cohort as the population of the United States continues to age. We developed a physiological signal data collection system based on a portable device and a smartphone and used it to acquire signal data from 62 older adults (72 ± 10 years old; 30 cognitively healthy, 31 with mild cognitive impairment, and 1 with Alzheimer’s disease) in three conditions: rest, psychological stress, and recovery. Through a classifier trained on this data and our own analysis, we show the different impacts of psychological stress in healthy and cognitively impaired older adults as well as in males and females. Our classifier achieved a 0.84 F1-score when discriminating between the rest and stress conditions. Our proposed system can be used as a continuous stress monitoring system in real-world settings that is non-invasive, portable, and easy to use.