Impact of mental stress on heart rate asymmetry

Abstract

This article studies the impact of mental stress induced by open-road driving on heart rate asymmetry (HRA), a physiological phenomenon that quantifies imbalance of heart rate acceleration and deceleration. Using ECG data of 10 individuals from a retrospective database from Physionet, three common HRA indexes (i.e., Porta Index-PI, Guzik Index-GI, and Slope Index-SI) were calculated within five minutes time windows across different stress levels. Results revealed that on average HRA significantly reduced by 2.1% with stress level (p<0.05) and HRA was lower in high stress, compared to moderate and low stress. Further pairwise comparison revealed that PI was significantly different between low and moderate stress (p=0.004) as well as moderate and high stress (p=0.047). Also, GI and SI were independent discriminators between low and moderate stress (p<0.001), and low and high stress (p<0.001). These results suggest that HRA can be used as a new biomarker for stress assessment.