Validation of Contact-Free Sleep Monitoring Device with Comparison to Polysomnography

• Published in: Journal of clinical sleep medicine Vol. 13; no. 3; pp. 517 - 522
• Main Authors: Tal, Asher, Shinar, Zvika, Shaki, David, Codish, Shlomi, Goldbart, Aviv
• Format: Journal Article
• Language: English
• Published: United States American Academy of Sleep Medicine 15.03.2017
• Subjects: Actigraphy - instrumentation; Actigraphy - methods; Adolescent; Adult; Aged; Emerging Technologies; Female; Heart Rate - physiology; Humans; Male; Middle Aged; Monitoring, Physiologic - instrumentation; Monitoring, Physiologic - methods; Movement - physiology; Polysomnography; Reproducibility of Results; Respiration; Sensitivity and Specificity; Sleep Wake Disorders - diagnosis; Sleep Wake Disorders - physiopathology; Smartphone; Young Adult; home sleep monitoring; sleep architecture; actigraphy; polysomnography
• ISSN: 1550-9389; 1550-9397; 1550-9397
• DOI: 10.5664/jcsm.6514

To validate a contact-free system designed to achieve maximal comfort during long-term sleep monitoring, together with high monitoring accuracy. We used a contact-free monitoring system (EarlySense, Ltd., Israel), comprising an under-the-mattress piezoelectric sensor and a smartphone application, to collect vital signs and analyze sleep. Heart rate (HR), respiratory rate (RR), body movement, and calculated sleep-related parameters from the EarlySense (ES) sensor were compared to data simultaneously generated by the gold standard, polysomnography (PSG). Subjects in the sleep laboratory underwent overnight technician-attended full PSG, whereas subjects at home were recorded for 1 to 3 nights with portable partial PSG devices. Data were compared epoch by epoch. A total of 63 subjects (85 nights) were recorded under a variety of sleep conditions. Compared to PSG, the contact-free system showed similar values for average total sleep time (TST), % wake, % rapid eye movement, and % non-rapid eye movement sleep, with 96.1% and 93.3% accuracy of continuous measurement of HR and RR, respectively. We found a linear correlation between TST measured by the sensor and TST determined by PSG, with a coefficient of 0.98 (R = 0.87). Epoch-by-epoch comparison with PSG in the sleep laboratory setting revealed that the system showed sleep detection sensitivity, specificity, and accuracy of 92.5%, 80.4%, and 90.5%, respectively. TST estimates with the contact-free sleep monitoring system were closely correlated with the gold-standard reference. This system shows good sleep staging capability with improved performance over accelerometer-based apps, and collects additional physiological information on heart rate and respiratory rate.