{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T17:12:55Z","timestamp":1770138775880,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,1,4]],"date-time":"2020-01-04T00:00:00Z","timestamp":1578096000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Cantonal Hospital St. Gallen and Empa St. Gallen","award":["15\/15"],"award-info":[{"award-number":["15\/15"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Sleep apnea (SA) is a prevalent disorder diagnosed by polysomnography (PSG) based on the number of apnea\u2013hypopnea events per hour of sleep (apnea\u2013hypopnea index, AHI). PSG is expensive and technically complex; therefore, its use is rather limited to the initial diagnostic phase and simpler devices are required for long-term follow-up. The validity of single-parameter wearable devices for the assessment of sleep apnea severity is still debated. In this context, a wearable electrocardiogram (ECG) acquisition system (ECG belt) was developed and its suitability for the classification of sleep apnea severity was investigated using heart rate variability analysis with or without data pre-filtering. Several classification algorithms were compared and support vector machine was preferred due to its simplicity and overall performance. Whole-night ECG signals from 241 patients with a suspicion of sleep apnea were recorded using both the ECG belt and patched ECG during PSG recordings. 65% of patients had an obstructive sleep apnea and the median AHI was 21 [IQR: 7\u201340]     h  \u2212 1     . The classification accuracy obtained from the ECG belt (accuracy: 72%, sensitivity: 70%, specificity: 74%) was comparable to the patched ECG (accuracy: 74%, sensitivity: 88%, specificity: 61%). The highest classification accuracy was obtained for the discrimination between individuals with no or mild SA vs. moderate to severe SA. In conclusion, the ECG belt provided signals comparable to patched ECG and could be used for the assessment of sleep apnea severity, especially during follow-up.<\/jats:p>","DOI":"10.3390\/s20010286","type":"journal-article","created":{"date-parts":[[2020,1,6]],"date-time":"2020-01-06T03:48:48Z","timestamp":1578282528000},"page":"286","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Classification of Sleep Apnea Severity by Electrocardiogram Monitoring Using a Novel Wearable Device"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1425-0428","authenticated-orcid":false,"given":"Florent","family":"Baty","sequence":"first","affiliation":[{"name":"Cantonal Hospital St. Gallen, Lung Center, Rorschacherstrasse 95, 9007 St. Gallen, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0994-9883","authenticated-orcid":false,"given":"Maximilian","family":"Boesch","sequence":"additional","affiliation":[{"name":"Cantonal Hospital St. Gallen, Lung Center, Rorschacherstrasse 95, 9007 St. Gallen, Switzerland"}]},{"given":"Sandra","family":"Widmer","sequence":"additional","affiliation":[{"name":"Cantonal Hospital St. Gallen, Lung Center, Rorschacherstrasse 95, 9007 St. Gallen, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8192-1391","authenticated-orcid":false,"given":"Simon","family":"Annaheim","sequence":"additional","affiliation":[{"name":"Empa, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland"}]},{"given":"Piero","family":"Fontana","sequence":"additional","affiliation":[{"name":"Empa, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland"}]},{"given":"Martin","family":"Camenzind","sequence":"additional","affiliation":[{"name":"Empa, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0946-682X","authenticated-orcid":false,"given":"Ren\u00e9 M.","family":"Rossi","sequence":"additional","affiliation":[{"name":"Empa, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0492-7172","authenticated-orcid":false,"given":"Otto D.","family":"Schoch","sequence":"additional","affiliation":[{"name":"Cantonal Hospital St. Gallen, Lung Center, Rorschacherstrasse 95, 9007 St. Gallen, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1612-3609","authenticated-orcid":false,"given":"Martin H.","family":"Brutsche","sequence":"additional","affiliation":[{"name":"Cantonal Hospital St. Gallen, Lung Center, Rorschacherstrasse 95, 9007 St. Gallen, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1217","DOI":"10.1164\/rccm.2109080","article-title":"Epidemiology of obstructive sleep apnea: A population health perspective","volume":"165","author":"Young","year":"2002","journal-title":"Am. 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