Electrophysiological Characteristics of Obstructive Sleep Apnea Syndrome with Insomnia: Polysomnography and Cardiopulmonary Coupling Analysis

Obstructive sleep apnea syndrome (OSA) and insomnia are two of most common sleep disorders encountered in the sleep clinic population, and substantial overlap between these two disorders was reported in previous studies. Considering a common concurrence of two disorders, understanding about characteristics of OSA with insomnia patients is important in order to optimize detection and treatment. However, little is known about OSA with insomnia patients’ unique characteristics, and clinicians tend to focus only on their respiratory symptoms in diagnosis and treatment. Overnight polysomnography (PSG) is the most commonly used test to diagnose sleep disorders, and especially it is gold standard for diagnosis of OSA. On the while, standard PSG is expensive and subjects feel inconvenience due to many electrodes and wires. Cardiopulmonary coupling (CPC) analysis is more convenient and less expensive because it uses a single channel electrocardiography (ECG) recording, and the association between the CPC indices and the sleep quality were proven in both OSA and insomnia in previous studies. The aim of this study is to characterize sleep and sleep quality of subjects with OSA with insomnia compared to OSA without insomnia in terms of PSG and CPC analysis.