{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:24:44Z","timestamp":1760059484506,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T00:00:00Z","timestamp":1750118400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Intramural Research Program of the National Institutes of Health","award":["ZIA ES101765"],"award-info":[{"award-number":["ZIA ES101765"]}]},{"DOI":"10.13039\/100000066","name":"National Institute of Environmental Health Sciences","doi-asserted-by":"publisher","award":["ZIA ES101765"],"award-info":[{"award-number":["ZIA ES101765"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>To elucidate the changes in gas exchange across the life course, we estimated the age trajectories of O2 saturation, CO2 (as either end-tidal or serum bicarbonate), resting heart rate, and resting respiratory rate from age 2 yr onward in female and male patients separately. We utilized two sources\u2019 data: electronic health records (EHR) representing ambulatory visits of approximately 53,000 individuals and sleep clinic polysomnogram (PSG) records representing an additional ~21,000. We used linear regression to estimate age-group-specific mean response levels for women and men. We compared estimated female\u2013male differences between pre- and post-pubertal children and between pre- and post-menopausal periods among adults. Women between 15 and 45 years had higher O2 saturation and lower serum bicarbonate levels or end-tidal CO2 levels than men of similar ages. For O2 saturation and for both measures of CO2, the female\u2013male difference was larger on average among adults at pre-menopausal ages than those at post-menopausal ages. Women had higher O2 saturation throughout their lives than men; however, the difference disappeared in the elderly. Women between menarche and menopause had significantly lower end-tidal CO2 and serum bicarbonate than men of similar ages. After menopause, however, women appeared to have higher mean levels of both end-tidal CO2 and serum bicarbonate than men.<\/jats:p>","DOI":"10.3390\/biom15060884","type":"journal-article","created":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T07:04:52Z","timestamp":1750143892000},"page":"884","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Age Trajectories of O2 Saturation and Levels of Serum Bicarbonate or End-Tidal CO2 Across the Life Course of Women and Men: Insights from EHR and PSG Data"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4208-0259","authenticated-orcid":false,"given":"Leping","family":"Li","sequence":"first","affiliation":[{"name":"Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA"},{"name":"Division of Sleep Medicine and Department of Neurology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8265-5307","authenticated-orcid":false,"given":"Min","family":"Shi","sequence":"additional","affiliation":[{"name":"Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7142-2812","authenticated-orcid":false,"given":"David M.","family":"Umbach","sequence":"additional","affiliation":[{"name":"Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC 27709, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zheng","family":"Fan","sequence":"additional","affiliation":[{"name":"Division of Sleep Medicine and Department of Neurology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"408","DOI":"10.1037\/0003-066X.54.6.408","article-title":"The origins of sex differences in human behavior","volume":"54","author":"Eagly","year":"1999","journal-title":"Am. 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