Comparison of pulse rate variability from post-auricula and heart rate variability during different body states for healthy subjects

Abstract

Heart rate variability (HRV) extracted from the electrocardiogram (ECG) is an essential indicator for assessing the autonomic nervous system in clinical. Some scholars have studied the feasibility of pulse rate variability (PRV) instead of HRV. However, there is little qualitative research in different body states. In this paper, the photoplethysmography (PPG) of postauricular and finger and the ECG of fifteen subjects were synchronously collected for comparative analysis. The eleven experiments were designed according to the daily living state, including the stationary state, limb movement state, and facial movement state. The substitutability of nine variables was investigated in the time, frequency, and nonlinearity domain by Passing Bablok regression and Bland Altman analysis. The results showed that the PPG of the finger was destroyed in the limb movement state. There were six variables of postauricular PRV, which showed a positive linear relationship and good agreement (p > 0.05, ratio $\le$0.2) with HRV in all experiments. Our study suggests that the postauricular PPG could retain the necessary information of the pulse signal under the limb movement state and facial movement state. Therefore, postauricular PPG could be a better substitute for HRV, daily PPG detection, and mobile health than finger PPG.

Keywords:

• Heart rate variability
• pulse rate variability
• postauricular photoplethysmography
• finger photoplethysmography
• different body states

Acknowledgements

The authors acknowledge the suggestions of each author and the cooperation of the subjects in this research.

Ethical approval

Any study involving human participants in this study was conducted in compliance with the Declaration of Helsinki. All experiments were non-invasive, painless, did not cause psychological pressure on the subject, and did not involve disease research. Therefore, according to the government documents of The Regulations of Ethical Reviews of Biomedical Research Involving Human Subjects, ethical review and approval was not required without disclosure of the subject’s personal privacy.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by grant No.20JR5RA438 from the Youth Foundation of Gansu Province and personal funding of Aihua Zhang.