Relationship between linear and nonlinear dynamics of heart rate and impairment of lung function in COPD patients

Abstract

Background

In chronic obstructive pulmonary disease (COPD), functional and structural impairment of lung function can negatively impact heart rate variability (HRV); however, it is unknown if static lung volumes and lung diffusion capacity negatively impacts HRV responses. We investigated whether impairment of static lung volumes and lung diffusion capacity could be related to HRV indices in patients with moderate to severe COPD.

Methods

Sixteen sedentary males with COPD were enrolled in this study. Resting blood gases, static lung volumes, and lung diffusion capacity for carbon monoxide (DL _CO) were measured. The RR interval (RRi) was registered in the supine, standing, and seated positions (10 minutes each) and during 4 minutes of a respiratory sinus arrhythmia maneuver (M-RSA). Delta changes (Δsupine-standing and Δsupine-M-RSA) of the standard deviation of normal RRi, low frequency (LF, normalized units [nu]) and high frequency (HF [nu]), SD1, SD2, alpha1, alpha2, and approximate entropy (ApEn) indices were calculated.

Results

HF, LF, SD1, SD2, and alpha1 deltas significantly correlated with forced expiratory volume in 1 second, DL _CO, airway resistance, residual volume, inspiratory capacity/total lung capacity ratio, and residual volume/total lung capacity ratio. Significant and moderate associations were also observed between LF/HF ratio versus total gas volume (%), r=0.53; LF/HF ratio versus residual volume, %, r=0.52; and HF versus total gas volume (%), r=−0.53 ( P<0.05). Linear regression analysis revealed that ΔRRi supine-M-RSA was independently related to DL _CO ( r=−0.77, r ²=0.43, P<0.05).

Conclusion

Responses of HRV indices were more prominent during M-RSA in moderate to severe COPD. Moreover, greater lung function impairment was related to poorer heart rate dynamics. Finally, impaired lung diffusion capacity was related to an altered parasympathetic response in these patients.

Journal

Journal ID (nlm-ta): Int J Chron Obstruct Pulmon Dis

Journal ID (iso-abbrev): Int J Chron Obstruct Pulmon Dis

Journal ID (publisher-id): International Journal of COPD

Title: International Journal of Chronic Obstructive Pulmonary Disease

Publisher: Dove Medical Press

ISSN (Print): 1176-9106

ISSN (Electronic): 1178-2005

Publication date Collection: 2015

Publication date (Electronic): 17 August 2015

Volume: 10

Pages: 1651-1661

Affiliations

[1 ]Cardiopulmonary Physiotherapy Laboratory, Federal University of São Carlos, São Carlos, Brazil

[2 ]Pulmonary Function and Clinical Exercise Physiology Unit, Respiratory Division, Department of Medicine, Federal University of São Paulo, São Paulo, Brazil

[3 ]Laboratory of Clinical Exercise Physiology, Division of Respiratory and Critical Care Medicine, Department of Medicine, Queen’s University, Kingston, ON, Canada

[4 ]Department of Physical Therapy and Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois Chicago, Chicago, IL, USA

Author notes

Correspondence: Audrey Borghi-Silva, Cardiopulmonary Physiotherapy Laboratory, Federal University of São Carlos, Rodovia Washington Luís, km 235, Bairro Monjolinho, CEP 13565-905 São Carlos, SP, Brazil, Tel [phone], Email audrey@ 123456ufscar.br

Article

Publisher ID: copd-10-1651

DOI: 10.2147/COPD.S81736

PMC ID: 4544724

Copyright statement: © 2015 Mazzuco et al. This work is published by Dove Medical Press Limited, and licensed under Creative Commons Attribution – Non Commercial (unported, v3.0) License

License:

The full terms of the License are available at http://creativecommons.org/licenses/by-nc/3.0/. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed.

Categories

Subject: Original Research