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It has already been extensively proven that snoring of patients with OSA acoustically differs significantly from habitual snoring. For this study, snoring in patients with OSA is analyzed by its different components: pitch, formants (F1-F3), formant-ratio F2\/F1, harmonic-noise-ratio (HNR), spectral energy ratio (SER). The objective of this study is to determine whether one or more acoustic parameters exhibit significant alterations or distinctive features immediately preceding an apneic episode, as compared to the patterns observed during simple snoring in individuals with obstructive sleep apnea (OSA). Identifying such preapneic indicators could facilitate the prediction of subsequent apnea events. With further technological advances and greater standardization, acoustical analysis could play a central role in the diagnosis and treatment of snoring and sleep apnea.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Based on the \u201cMunich-Passau Snore Sound Corpus\u201d (MPSSC) as one of the world\u2019s largest data sets for snoring sounds, retrospective data, consisting of 219 patients with OSA, were obtained using drug-induced sleep endoscopy (DISE). The mentioned components were retrieved and analyzed with the open source software \u201ePraat\u201c. Statistical testing was done with t-tests (Student and Welch) and Mann-Whitney-U-test.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>For four parameters (F1, F2\/F1, HNR, logSER) there are statistically significant differences between continuous\/simple and preapneic snoring sounds.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Preapneic snoring sounds seem to have different characteristics than continuous\/simple snoring sounds. With further research, a simple acoustic differentiation for various diagnostic purposes could become possible.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s11325-025-03568-w","type":"journal-article","created":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T16:15:37Z","timestamp":1770999337000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Possible predictors of apneic-events during sleep: advanced snoring sound analysis"],"prefix":"10.1007","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4471-848X","authenticated-orcid":false,"given":"Malte","family":"Unkell","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7453-5612","authenticated-orcid":false,"given":"Maximilian","family":"Schmitt","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5835-3699","authenticated-orcid":false,"given":"Winfried","family":"Hohenhorst","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9441-5287","authenticated-orcid":false,"given":"Christoph","family":"Janott","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3091-0331","authenticated-orcid":false,"given":"Michael","family":"Herzog","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6301-2891","authenticated-orcid":false,"given":"Clemens","family":"Heiser","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2026,2,13]]},"reference":[{"key":"3568_CR1","doi-asserted-by":"publisher","first-page":"2413","DOI":"10.1002\/lary.25346","volume":"125","author":"N Bhattacharyya","year":"2015","unstructured":"Bhattacharyya N (2015) Sleep and health implications of snoring: a populational analysis. 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The dataset was not created specifically for this study. Accordingly, this article does not contain any studies with human participants performed by any of the authors. The study was approved on th 21\u2009st February 2023 by the ethics committee of the Technical University Munich.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"The authors did not receive support from any organization for the submitted work. Christoph Janott is shareholder of Diametos GmbH. Clemens Heiser reports grants from Nyxoah and Inspire Medical Systems (paid to the Technical University of Munich), and consultancy fees, payment or honoraria for lectures, presentations, or educational events, and support for attending meetings from Nyxoah, Inspire Medical Systems and XM Consult:. In addition, C. Heiser is founder of the Institute for Sleep Medicine and LunaLab. Michael Herzog does not have a conflict of interest. Winfried Hohenhorst does not have a conflict of interest. Maximilian Schmitt does not have a conflict of interest. Malte Unkell does not have a conflict of interest.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}],"article-number":"48"}}