HHT based cardiopulmonary coupling analysis for sleep apnea detection
Dongdong Liu, Xiaochen Yang, Guangfa Wang, Jing Ma, Yanhui Liu, Chung-Kang Peng, Jue Zhang, Jing Fang
Sleep Medicine 13(5):503-509, May 2012
To validate the feasibility of the Hilbert–Huang transform (HHT) based cardiopulmonary coupling (CPC) technique in respiratory events detection and estimation of the severity of apnea/hypopnea.
The HHT-CPC spectrum provides much finer temporal resolution and frequency resolution (8s and 0.001Hz) compared with the original CPC (8.5min and 0.004Hz). The area under the ROC curve of pLFC was 0.79 in distinguishing respiratory events from normal breathing. Significant differences were found in TVDF among groups with different severities of OSAHS (normal, mild, moderate, and severe, p<0.001). TVDF has a strong negative correlation with the apnea/hypopnea index (AHI, correlation coefficient −0.71).
The spectrographic markers, pLFC and TVDF can be used to identify respiratory events and represent the disruption extent of sleep architecture in patients with sleep apnea/hypopnea, respectively.