IMPACT OF COVID-19 ON HEART RATEVARIABILITY AND PULMONARY FUNCTION TESTS PARAMETERSAMONG PATIENTS WITH CHRONIC LUNG DISEASES - A CROSS SECTIONAL STUDY

Abstract

Introduction : Covid 19 pandemic, a contagious disease caused by virus, SARS- Cov-2 affected many systems in human body, predominantly respiratory and cardiovascular system.But these effects on the autonomicnervous system (ANS) in different locations in the world, over the long term remain unclear. Therefore, we tried to evaluate the alterations in cardiac autonomic functioning with long-term manifestations in population with chronic lung diseases of South India. Impaired lung compliance may have changes in pulmonary function tests (PFT) in chronic lung diseases along with variations in heart rate variability (HRV). HRV gives information about sympathovagal autonomic drives and used as a tool for the assessment of autonomic imbalance. Analysis of the beat to beat variation of cardiac R-R intervals has been used to quantify alteration in cardiac autonomic regulation.

Aim: To study the association of Covid – 19 with HRV and PFT among patients with chronic lung diseases.

Materials and methods: A cross sectional study was conducted in patients with interstitial lung diseases (ILD) and chronic obstructive pulmonary diseases (COPD) who had contracted with covid -19 and compared with control group of non covid ILD and COPD patients. Spectral analysis of HRV and PFT were taken in both groups and compared the changes. A total of 90 ILD and 125 COPD patients of age group 55-65 years were studied and compared with age and sex matched control group.

Results: The difference of PFT and HRV in both groups were analyzed by unpaired ‘T’ test and the difference of categorical variable in both groups wereanalyzed by Chisquare test.

All the covid patients, showed an increase in sympathetic activity irrespective of gender. Low Frequency and High Frequency Ratio (LF:HF ratio) was significantly more in females with Covid 19 compared to that of males. FEV1 % pred. was less in both the gender but females showed better values (73%).

Conclusion: There were significant changes in Lfnu, HFnu and LF/HF ratio (p ≤ 0.001), FEV1 % pred., FEV1/ FVC ratio predicted and PEF among both COPD and ILD patients when compared with Covid infected patients and shows that there increase in sympathetic tone with Covid infection.