Contactless sleep monitoring using the Sonomat in children with Down syndrome

Children with Down syndrome (DS) require multiple sleep studies throughout childhood to diagnose and monitor sleep disordered breathing (SDB). Previous research suggests sensors applied during polysomnography (PSG) are poorly tolerated by children with DS. The Sonomat is a contactless device previously validated in typically developing children, and adult populations. Our study aimed to compare simultaneous Sonomat and PSG recordings in children with DS to determine the suitability of the Sonomat for use in this population. Fifty children with DS undergoing diagnostic PSG were recruited from the Queensland Children's Hospital sleep laboratory. Agreement for sleep and respiratory parameters were assessed using concordance correlation coefficients (CCC), while detection and classification of SDB were assessed using indicators such as sensitivity, specificity, likelihood ratios, and receiver operator characteristic curves. Comparison of parameters including the apnea-hypopnea index (CCC=89%; 95%CI 76, 93), and obstructive events index (CCC=74%; 95%CI 44, 88) showed reasonable agreement between Sonomat and PSG. The Sonomat showed outstanding ability to differentiate between the presence and absence of SDB (area under the curve [AUC]=0.97; 95%CI 0.93, 1.00), though we are uncertain of its ability to classify SDB profile and severity due to sample size limitations resulting in wide confidence intervals. The easy-to-use, non-invasive nature of the Sonomat make it ideal for use in the screening of SDB in children with DS. Further data are needed to determine its suitability for classifying SDB profile and severity, including within the home, and for its use in other neurodevelopmental groups.