A comparison of respiratory metrics from a patch-based 2-EEG channel full PSG device and a traditional PSG device in a large, multi-center clinical trial.

Introduction: The gold standard for sleep monitoring is in-lab, polysomnography (PSG), an expensive test that places unnecessary burden on the patient, is uncomfortable, and which due to a lack of personnel and hospital resources cannot meet current and future demands for sleep testing. Onera has developed the first wireless, patch-based PSG, the Onera Sleep Test System (STS), which consists of four disposable patches and four reusable pods that allows for PSG studies to be performed outside of the clinic while maintaining the standards of an in-lab attended PSG.

Methods: 206 subjects with a suspected sleep disorder recruited from 7 clinical sites in Germany underwent a single-night simultaneous in-lab PSG and patch-based PSG recording. Studies were blind scored by three independent scorers according to AASM criteria providing 618 records for the analysis. Respiratory metrics were compared between the devices using correlation and classification metrics.

Results: The subjects were middle-aged and mildly obese (50.9±12.3 years of age, BMI 30.2±6.2). There was a strong positive correlation of the AHI 3% (0.91), Apnea Index (AI) (0.90), Central Apnea Index (0.84), Obstructive Apnea Index (0.86), Hypopnea Index 3% or arousal (0.70), and arousal index (0.87) between the devices. The accuracy, sensitivity, and specificity of the patch-based PSG for AHI≥5 were 0.86, 0.85, and 0.75; for AHI≥15, it was 0.83, 0.78, and 0.92; and for AHI ≥ 30, it was 0.84, 0.82, and 0.97, respectively.

Conclusion: The scored data from the patch-based PSG system was positively correlated with that from the in-lab PSG. The patch-based PSG showed a high-level of diagnostic agreement at accepted AHI thresholds. A high specificity for moderate and severe sleep apnea indicates that the patch-based PSG can accurately identify patients at risk of developing adverse cardiovascular events.

Publication History

Article published online:
18 March 2025