Cardio-respiratory coordination increases during sleep apnea.
Cardiovascular diseases are the main source of morbidity and mortality in the United States with costs of more than $170 billion. Repetitive respiratory disorders during sleep are assumed to be a major cause of these diseases. Therefore, the understanding of the cardio-respiratory regulation during these events is of high public interest. One of the governing mechanisms is the mutual influence of the cardiac and respiratory oscillations on their respective onsets, the cardio-respiratory coordination (CRC). We analyze this mechanism based on nocturnal measurements of 27 males suffering from obstructive sleep apnea syndrome. Here we find, by using an advanced analysis technique, the cardiogram, not only that the occurrence of CRC is significantly more frequent during respiratory sleep disturbances than in normal respiration (p-value<10(-51)) but also more frequent after these events (p-value<10(-15)). Especially, the latter finding contradicts the common assumption that spontaneous CRC can only be observed in epochs of relaxed conditions, while our newly discovered epochs of CRC after disturbances are characterized by high autonomic stress. Our findings on the connection between CRC and the appearance of sleep-disordered events require a substantial extension of the current understanding of obstructive sleep apneas and hypopneas.
Cardiovascular Physics, Department of Physics, Humboldt-Universität zu Berlin, Berlin, Germany.
Maik
M
Riedl
Cardiovascular Physics, Department of Physics, Humboldt-Universität zu Berlin, Berlin, Germany.
Andreas
A
Müller
Cardiovascular Physics, Department of Physics, Humboldt-Universität zu Berlin, Berlin, Germany.
Jan F
JF
Kraemer
Department for Cardiology, Sleep Medicine Centre, Charité Universitätsmedizin Berlin, Berlin, Germany.
Thomas
T
Penzel
Cardiovascular Physics, Department of Physics, Humboldt-Universität zu Berlin, Berlin, Germany; Research Domain on Transdisciplinary Concepts and Methods, Potsdam Institute for Climate Impact Research, Potsdam, Germany.
Juergen
J
Kurths
Cardiovascular Physics, Department of Physics, Humboldt-Universität zu Berlin, Berlin, Germany.
Niels
N
Wessel
D000328:Adult; D001341:Autonomic Nervous System / Q000503:physiopathology*; D002318:Cardiovascular Diseases / Q000209:etiology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008955:Models, Cardiovascular; D056152:Respiratory Rate / Q000502:physiology*; D012891:Sleep Apnea Syndromes / Q000150:complications / Q000503:physiopathology*; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology