Efficient and cost-effective estimation of the influence of respiratory variables on respiratory sinus arrhythmia.
Researchers are interested in respiratory sinus arrhythmia (RSA) as an index of cardiac vagal activity. Yet, debate exists about how to account for respiratory influences on quantitative indices of RSA. T. Ritz, M. Thons, and B. Dahme (2001) developed a within-individual correction procedure by which the effects of respiration on RSA may be estimated using regression models. We replicated their procedure substituting a spectral high-frequency measure of RSA for a time-domain statistic and a respiratory belt's relative measure of tidal volume for the direct assessment provided by a pneumotachograph. The standardized slopes from the respiratory belt and pneumotachography-derived regression equations (estimated across a 6-min paced breathing protocol) were positively correlated (r=0.93, p<.001); correlations were similar across 2- and 4-min time courses parsed from the 6-min protocol. Our results offer methodological alternatives to the research community.
Egizio
Victoria B
VB
Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15213, USA. vbe1@pitt.edu
Eddy
Michael
M
Robinson
Matthew
M
Jennings
J Richard
JR
D001146:Arrhythmia, Sinus / Q000503:physiopathology*; D003362:Cost-Benefit Analysis; D003627:Data Interpretation, Statistical; D004562:Electrocardiography / Q000191:economics / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D012044:Regression Analysis; D015656:Respiratory Mechanics / Q000502:physiology*; D013990:Tidal Volume / Q000502:physiology; D055815:Young Adult