CHRONIC OBSTRUCTIVE PULMONARY DISEASE: GRADING OF SEVERITY AS REFLECTED BY SHORT TERM HEART RATE VARIABILITY.

Abstract

Chronic obstructive pulmonary disease (COPD) is a broad spectrum respiratory illness where there are structural and functional changesin the lungs. According to WHO, COPD is a leading global burden and by 2030 it will be the third leading cause of death worldwide. The structural and functional changes in the lungs in COPD patients tend to inuence the cardiac autonomic functions and heart rate variability (HRV). Previousstudiesshow that there is decrease in heart rate variability in COPD patients. In many previousstudies, it isfound that results ofshort term HRV analysis of 5minutes is comparable to standard 24hours HRV analysis and is very patient friendly and reproducible procedure to analyse the cardiac autonomic functions. So determination of parameters of cardiac autonomic functions with the help of short term HRV analysis in COPD patients is helpful in determining the pathophysiology and subsequent management of such patients. A Descriptive and observational study was conducted upon 100 previously diagnosed COPD patients at the Autonomic function research Laboratory, Department of Physiology, R G Kar Medical College and Hospital, Kolkata, West Bengal. The study includes short term (5min) HRV analysis in COPD patients between the age group 18years and 60years after fullling appropriate inclusion and exclusion criteria and the results were analyzed using proper statistical software. After analysis of different data it was found that there is decrease in heart rate variability (in both Time domain and Frequency domain analysis) in case of COPD and also the decrease is more in case of increasing severity grading of COPD. Sympathetic activity increases and vagal or parasympathetic activity upon heart rate decreases with the increase in COPD grading. Further studies with more number of subjects will be helpful in assessing pathophysiology and management of COPD patients with the help of HRV analysis.