Towards Phenotyping Suppressed Anger in Perimenopausal Women with Lyfas Biomedical Application: A Comprehensive Diagnostic Reliability Study

Biomedical applications are gaining popularity in decoding human emotion. Anger causes sympathetic overdrive and is a normal emotion, which is either expressed or kept suppressed. Suppressed anger (SA) is a major health issue often causing serious cardiometabolic and mental diseases due to cardiac autonomic neuropathy (CAN), where the sympathovagal homeostasis is compromised to compensate for it. Lyfas is a smartphone-based biomedical application that captures CAN through short (120 sec) heart rate variability (HRV) and its associated cardiovascular optical biomarkers (COBs). This paper attempts to diagnose SA with the help of Lyfas COBs and a few important physical parameters in a cohort of Indian perimenopausal women (N=415; case 205 and control 210), who suffer from mood dysregulation due to the depletion of natural estradiol (E2) in the brain. The clinical Anger Scale (CAS), a gold-standard anger assessment tool is taken into consideration as a reference scale. The strength of correlations of each COB and physical parameter with CAS and its reliability is calculated using Spearman’s correlation and Bland-Altman’s reliability assessment, respectively. The paper concludes that COBs such as SDNN, RMSSD, and LF/HF along with physical parameters (BMI) are hallmark biomarkers for SA phenotypes with 71% of accuracy, 74% of j-statistics, as well as 92% of precision. Early diagnosis of SA with Lyfas would facilitate early treatment, and thereby improve the quality of life.