Simultaneous Measurement of Respiratory and Pulse Information Using a Patch-Type Sensor for Sleep Apnea Hypopnea Detection

Sleep apnea hypopnea syndrome (SAHS) is one of the most common sleeping disorders. However, numerous people suffering from SAHS are left undiagnosed. SAHS causes arousal reactions, sleep fragmentation, and hypoxemia, thus leading to excessive daytime sleepiness, lack of concentration, and a high risk of cardiovascular complications. Although polysomnography is the standard way of SAHS screening, its high cost, limited accessibility, and requirement of operational skills hinder its applicability for SAHS diagnoses. Therefore, this letter proposes a novel approach for SAHS detection using a patch-type photoplethysmography sensor. As an initial study, both respiratory and pulse information are simultaneously measured, and the trend of pulse variation, which reportedly has a strong correlation to oxygen saturation (SpO
₂
), is thereby clarified. In addition, more real-time measurement of the pulse rate was possible on the chest compared to the fingertip. SAHS detection by incorporating respiratory and pulse information is beneficial for complete and credible screening and risk assessment of cardiovascular complications with less invasive devices. Therefore, this simple patch-type sensor can replace invasive, expensive, and limiting screening methods to facilitate the diagnosis of SAHS.