{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:26:30Z","timestamp":1791332790487,"version":"4.3.1"},"reference-count":44,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100016132","name":"Jabbs Foundation","doi-asserted-by":"publisher","award":["1128402"],"award-info":[{"award-number":["1128402"]}],"id":[{"id":"10.13039\/501100016132","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["physoc.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Experimental Physiology"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Acute mountain sickness (AMS) affects many individuals ascending to high altitude annually, carrying potential morbidity and mortality risks (e.g., high\u2010altitude cerebral oedema). The objective of this pilot study was to record overnight pulse oximetry during ascent to 4554\u00a0m and determine whether: (1) extracted overnight biomarkers had any relationship to AMS; and (2) AMS at 4554\u00a0m could be predicted by oximetry biomarkers using classification models trained\/validated on overnight data from lower altitudes. Twenty lowlanders (five females, 36.8\u00a0\u00b1\u00a018.5 years old) completed a 4\u00a0day ascent to 4554\u00a0m, where AMS status was determined by clinical examination. Oximetry was recorded continuously each night, with &gt;40 biomarkers extracted and compared between AMS and non\u2010AMS. Exploratory classification models (5\u2010fold cross\u2010validation) were tested for nightly data with a systematic approach to feature selection. Model performances were evaluated based on predictions of AMS at 4554\u00a0m. A significant effect of ascent was observed for many overnight biomarkers; however, no effect of AMS status was evident, nor were any differences observed between AMS and non\u2010AMS for any overnight biomarkers during ascent. AMS at 4554\u00a0m was most accurately predicted from overnight recordings collected at 2600\u00a0m (accuracy, 100%; true positive rate, 100%) and 3647\u00a0m (accuracy, 80%; true positive rate, 90.9%) using\n                    <jats:italic>k<\/jats:italic>\n                    \u2010nearest neighbour and support vector machine classification models. Biomarkers were extracted from overnight oximetry recordings, with limited differences observed between AMS and non\u2010AMS. In conclusion, AMS at 4554\u00a0m can be predicted from overnight oximetry using machine learning; however, these preliminary findings need confirmation in a larger cohort, with additional investigation into the most clinically relevant biomarkers.\n                  <\/jats:p>","DOI":"10.1113\/ep093777","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T17:10:27Z","timestamp":1790788227000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Prediction of acute mountain sickness occurring at 4554\u00a0m using overnight pulse oximetry from lower altitude: A pilot study"],"prefix":"10.1113","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4116-2025","authenticated-orcid":false,"given":"Luke","family":"Cutts","sequence":"first","affiliation":[{"name":"Salford Royal NHS Trust  Salford UK"},{"name":"Medical School for Birmingham Medical Research Expeditionary Society University of Birmingham  Birmingham UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kim","family":"Ashdown","sequence":"additional","affiliation":[{"name":"Medical School for Birmingham Medical Research Expeditionary Society University of Birmingham  Birmingham UK"},{"name":"Occupational Performance Research Group University of Chichester  Chichester UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ciaran","family":"Simpkins","sequence":"additional","affiliation":[{"name":"Medical School for Birmingham Medical Research Expeditionary Society University of Birmingham  Birmingham UK"},{"name":"Medical School University of Birmingham  Birmingham UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Will","family":"Trender","sequence":"additional","affiliation":[{"name":"Medical School for Birmingham Medical Research Expeditionary Society University of Birmingham  Birmingham UK"},{"name":"Restorative Neurosciences Imperial College London  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Clarke","sequence":"additional","affiliation":[{"name":"Medical School for Birmingham Medical Research Expeditionary Society University of Birmingham  Birmingham UK"},{"name":"Anaesthesia &amp; Intensive Care Medicine Royal Blackburn Teaching Hospital, NHS Trust  Blackburn UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Delamere","sequence":"additional","affiliation":[{"name":"Medical School for Birmingham Medical Research Expeditionary Society University of Birmingham  Birmingham UK"},{"name":"Medical School University of Birmingham  Birmingham UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8713-2457","authenticated-orcid":false,"given":"Samuel J. 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