Key result
10-second PPG data predicts the Baevsky stress index with an R2 of ~0.70.
Why the study?
Traditional ultra-short-term stress measurement using HRV or PRV requires over one minute, limiting real-time stress monitoring and accurate prediction.
Does ultra-short-term PPG measurement (under 1 minute) accurately predict stress indices compared to standard 1-minute measurements in healthy adults?
Does ultra-short-term PPG measurement (under 1 minute) accurately predict stress indices compared to standard 1-minute measurements in healthy adults?
Ultra-short-term PPG measurements of at least 10 seconds, combined with machine learning regression, can effectively predict physiological stress indices, enabling real-time monitoring.
May support wearable stress monitoring in research; leaves open clinical validation and outcome studies before adoption.
Stress is a direct or indirect cause of reduced work efficiency in daily life. It can damage physical and mental health, leading to cardiovascular disease and depression. With increased interest and awareness of the risks of stress in modern society, there is a growing demand for quick assessment and monitoring of stress levels. Traditional ultra-short-term stress measurement classifies stress situations using heart rate variability (HRV) or pulse rate variability (PRV) information extracted from electrocardiogram (ECG) or photoplethysmography (PPG) signals. However, it requires more than one minute, making it difficult to monitor stress status in real-time and accurately predict stress levels. In this paper, stress indices were predicted using PRV indices acquired at different lengths of time (60 s, 50 s, 40 s, 30 s, 20 s, 10 s, and 5 s) for the purpose of real-time stress monitoring. Stress was predicted with Extra Tree Regressor, Random Forest Regressor, and Gradient Boost Regressor models using a valid PRV index for each data acquisition time. The predicted stress index was evaluated using an R2 score between the predicted stress index and the actual stress index calculated from one minute of the PPG signal. The average R2 score of the three models by the data acquisition time was 0.2194 at 5 s, 0.7600 at 10 s, 0.8846 at 20 s, 0.9263 at 30 s, 0.9501 at 40 s, 0.9733 at 50 s, and 0.9909 at 60 s. Thus, when stress was predicted using PPG data acquired for 10 s or more, the R2 score was confirmed to be over 0.7.
No takes yet. Share an insight, caveat, or question.
Lee et al. (2023) studied Stress (n=17). Ultra-short-term PPG data acquisition (10 to 60 seconds) vs. Standard 1-minute PPG measurement was evaluated on R2 score between the predicted stress index and the actual Baevsky Stress Index calculated from one minute of the PPG signal. Predicting the stress index using photoplethysmography (PPG) data acquired for 10 seconds or more achieved an R2 score of over 0.70 compared to standard 1-minute measurements.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: