Correlation of Heart Rate Variability as a Measure of Autonomic Dysregulation in Stable Chronic Obstructive Pulmonary Disease

Background: Chronic obstructive pulmonary disease (COPD) affects not only the lungs but also the cardiovascular system and other organs, contributing to high morbidity and mortality. Recent studies suggest that patients with COPD exhibit autonomic dysfunction, which may increase the risk of cardiovascular mortality. Therefore, early detection and close monitoring of autonomic dysfunction in COPD patients are essential. Methods: Patients were recruited using a convenience sampling method. Data on sociodemographic characteristics were collected, and assessments included the St. George’s Respiratory Questionnaire (SGRQ), spirometry, six-minute walk test (6MWT), and heart rate variability (HRV). Data were analyzed using standard statistical methods. Results: A total of 47 patients were included in the study. Sociodemographic variables, habitual and environmental factors, spirometric characteristics, and clinicophysiological profiles were analyzed in relation to COPD parameters. No significant correlation was found between the body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index and HRV parameters, nor between COPD severity and HRV frequency- and time-domain measures. However, a significant negative association was observed between the duration of COPD and HRV time-domain parameters. Specifically, COPD duration was negatively correlated with the root mean square of successive differences between normal heartbeats (rMSSD; r = -0.324, p = 0.026). Additionally, a significant negative correlation was found between the SGRQ impact score and standard deviation of NN intervals (SDNN). Conclusion: These findings support the concept that autonomic dysregulation is an integral component of COPD pathophysiology. HRV is a simple, non-invasive biomarker for assessing autonomic nervous system function in patients with COPD and may help identify those at increased cardiovascular risk. Incorporating HRV evaluation, particularly through standardized long-term monitoring, into routine clinical assessment may enhance disease stratification, prognostication, and personalized management.