Kabir, M.Dimitri, H.Sanders, P.Antic, R.Nalivaiko, E.Abbott, D.Baumert, M.Dheda, K.2010-08-022010-08-022010PLoS One, 2010; 5(5):e10602-1-e10602-121932-62031932-6203http://hdl.handle.net/2440/59569Cardiac and respiratory rhythms reveal transient phases of phase-locking which were proposed to be an important aspect of cardiorespiratory interaction. The aim of this study was to quantify cardio-respiratory phase-locking in obstructive sleep apnea (OSA). We investigated overnight polysomnography data of 248 subjects with suspected OSA. Cardiorespiratory phase-coupling was computed from the R-R intervals of body surface ECG and respiratory rate, calculated from abdominal and thoracic sensors, using Hilbert transform. A significant reduction in phase-coupling was observed in patients with severe OSA compared to patients with no or mild OSA. Cardiorespiratory phase-coupling was also associated with sleep stages and was significantly reduced during rapid-eye-movement (REM) sleep compared to slow-wave (SW) sleep. There was, however, no effect of age and BMI on phase coupling. Our study suggests that the assessment of cardiorespiratory phase coupling may be used as an ECG based screening tool for determining the severity of OSA.en© 2010 Kabir et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Humans; Polysomnography; Body Mass Index; Sleep Stages; Demography; Heart Rate; Respiration; Aging; Adult; Aged; Middle Aged; Young Adult; Time Factors; Sleep Apnea, Obstructive; Sex Characteristics; Electrocardiography; Female; Male; HeartJournal article00200976632010080111561310.1371/journal.pone.001060292 Health9202 Health and Support Services920203 Diagnostic Methods09 Engineering0906 Electrical and Electronic Engineering090609 Signal Processing0002776335000072-s2.0-7795627802334238Sanders, P. [0000-0003-3803-8429]Abbott, D. [0000-0002-0945-2674]Baumert, M. [0000-0003-2984-2167]