Assessment of Subclinical Derangement of Cardiovascular Autonomic Regulation in Stable Asthmatic Patients
Background and Aim: Autonomic nervous system (ANS) is linked to asthma. The ANS controls several aspects of airway function. It was planned to assess the autonomic cardiovascular regulation in stable asthmatic patients by short‑term heart rate variability (HRV) analysis. Methods: The present study was conducted in the Department of Respiratory Medicine in collaboration with the Department of Physiology, Pt. B.D.S PGIMS, Rohtak in a total of eighty subjects/patients with comparable age, sex, weight, and height. Two groups with forty subjects/ patients in each were formed as follows: Group 1: stable asthmatics and Group 2: nonasthmatics (controls). Electrocardiography and HRV of the participants were measured using digitalized polyrite‑D as per the standard protocol. Results: Frequency domain parameters showed statistically significant difference between two groups. Low frequency (LF) (nu) was (48.9 ± 17.8 vs. 53.3 ± 16.9) significantly less (P < 0.05), while high frequency (HF) (nu) significantly more (41.4 ± 15.19 vs. 38.3 ± 1.2) in Group 1 as compared to Group 2. LF/HF (1.2 ± 0.6 vs. 1.39 ± 0.78) ratio was decreased significantly (P < 0.05) in Group 1. Conclusion: An overall reduced HRV (sympathetic activity) and deranged sympathovagal balance with vagal dominance (decreased LF, increased HF) in stable asthmatics. Hence, HRV could serve as a potential noninvasive tool to assess autonomic cardiovascular regulation in asthmatics.