Comparison of Ring Pulse Oximetry Using Reflective Photoplethysmography and PSG in the Detection of OSA in Chinese Adults: A Pilot Study

• Published in: Nature and science of sleep Vol. 14; pp. 1427 - 1436
• Main Authors: Zhao, Rui, Xue, Jianbo, Zhang, Xueli, Peng, Maohuan, Li, Jing, Zhou, Bing, Zhao, Long, Penzel, Thomas, Kryger, Meir, Dong, Xiao Song, Gao, Zhancheng, Han, Fang
• Format: Journal Article
• Language: English
• Published: Macclesfield Dove Medical Press Limited 31-08-2022; Taylor & Francis Ltd; Dove; Dove Medical Press
• Subjects: Adults; Algorithms; Automation; Comparative analysis; Heart rate; Hypoxia; Laboratories; obstructive sleep apnea; Original Research; Oximetry; Oxygen saturation; Patient monitoring equipment; Pattern recognition; polysomnography; Pulse oximetry; reflective photoplethysmography; Signal processing; Sleep apnea; Sleep apnea syndromes; Sleep disorders; Software; China; United States > US
• ISSN: 1179-1608; 1179-1608
• DOI: 10.2147/NSS.S367400

Objective: A novel ring-worn oximeter (Circul) uses reflective photoplethysmography and automated signal processing to calculate oxygen desaturations. We evaluated the ability of Circul to detect obstructive sleep apnea in Chinese adults. Methods: We recruited 207 Chinese Han subjects: 70% males, mean age 48.2[+ or -]14.7 years, mean BMI 27.6[+ or -]4.8 kg/m2 and mean AHI 28.6[+ or -]25.2 events/h. All participants underwent simultaneous polysomnography (PSG) and Circul testing in a sleep laboratory. Oxygen desaturation index (ODI), mean oxygen saturation (MSp[O.sub.2]), cumulative time at SpO2<90% (CT90), cumulative percentage of sleep time spent with SpO2<90% (CT90/TST) were derived and compared for the Circul and the PSG. Results: The ODI was 25.3[+ or -]24.5 events/h using PSG and 22.2[+ or -]24.5 events/h using Circul (P<0.0001), with an intraclass correlation coefficient (ICC) of 0.884. CT90 and CT90/TST between the two methods were not different; the MSp[O.sub.2] level calculated by PSG was slightly lower than Circul, 95.0% (93.0-96.0%) vs 95.3% (93.9-96.6%), P<0.0001. Circul-ODI had a good correlation (r=0.91, p<0.0001) and close agreement with PSG-AHI (Bland-Altman analysis: Mean Difference 6.4, 95% CI -14.8 to 27.5 events/h). Using a threshold of AHI [greater than or equal to]5 events/h, the Circul had 87% sensitivity, 83% specificity, 5.09 positive likelihood ratio (LR+), 86% accuracy, and 0.929 area under the curve (AUC). Conclusion: Circul ring pulse oximetry can detect OSA with reasonable reliability. The Circul system is a reliable and comfortable choice for OSA assessment. Keywords: obstructive sleep apnea, reflective photoplethysmography, pulse oximetry, polysomnography