{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T02:34:16Z","timestamp":1791513256759,"version":"4.3.4"},"reference-count":47,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,16]],"date-time":"2021-06-16T00:00:00Z","timestamp":1623801600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100011103","name":"Sixth Framework Programme","doi-asserted-by":"publisher","award":["5048944"],"award-info":[{"award-number":["5048944"]}],"id":[{"id":"10.13039\/100011103","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPM"],"abstract":"<jats:p>Patients with obstructive sleep apnea syndrome (OSAS) exhibit low cardio-fitness impact, attributed to fragmented sleep architecture and associated pathophysiological sequelae. The purpose of our study was to investigate fitness indicators during 6-min walk test (6MWT) and oxidative stress markers in apnea-hypopnea index (AHI) in OSAS patients stratified by severity. A total of 37 newly diagnosed patients, comorbidity-free, were divided into two groups: (Moderate OSAS (n = 12), defined as \u2265 15 AHI &lt; 30 events per hour; Age: 50.7 \u00b1 7.2 years, BMI: 32.5 \u00b1 4.0 kg\/m2 vs. Severe OSAS (n = 25), defined as AH\u0399 \u2265 30 events per hour; Age: 46.3 \u00b1 10.4 years, BMI: 33.3 \u00b1 7.9 kg\/m2). Measurements included demographics, anthropometric characteristics, body composition, blood sampling for reactive oxygen metabolites\u2019 levels (d-ROM) and plasma antioxidant capacity (PAT), and followed by a 6MWT. AHI was significantly associated with d-ROMs levels, chest circumference in maximal inhalation and exhalation (\u0394chest), neck circumference, as well as 6MWT-derived indices. In conclusion, our study determines bidirectional interrelationships between OSAS severity and anthropometrics, body composition, and fitness metrics. These findings indicate that the impact of OSAS should be evaluated well beyond polysomnography-derived parameters.<\/jats:p>","DOI":"10.3390\/jpm11060563","type":"journal-article","created":{"date-parts":[[2021,6,16]],"date-time":"2021-06-16T10:27:07Z","timestamp":1623839227000},"page":"563","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["The 6-Minute Walk Test and Anthropometric Characteristics as Assessment Tools in Patients with Obstructive Sleep Apnea Syndrome. A Preliminary Report during the Pandemic"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2437-5339","authenticated-orcid":false,"given":"Vasileios T.","family":"Stavrou","sequence":"first","affiliation":[{"name":"Laboratory of Cardio-Pulmonary Testing and Pulmonary Rehabilitation, Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0413-4028","authenticated-orcid":false,"given":"George D.","family":"Vavougios","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"},{"name":"Department of Computer Science and Telecommunications, University of Thessaly, 35131 Lamia, Greece"},{"name":"Department of Neurology, Athens Naval Hospital, 11521 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyriaki","family":"Astara","sequence":"additional","affiliation":[{"name":"Laboratory of Cardio-Pulmonary Testing and Pulmonary Rehabilitation, Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7688-8072","authenticated-orcid":false,"given":"Dimitra I.","family":"Siachpazidou","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eirini","family":"Papayianni","sequence":"additional","affiliation":[{"name":"Laboratory of Cardio-Pulmonary Testing and Pulmonary Rehabilitation, Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Konstantinos I.","family":"Gourgoulianis","sequence":"additional","affiliation":[{"name":"Laboratory of Cardio-Pulmonary Testing and Pulmonary Rehabilitation, Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"},{"name":"Department of Respiratory Medicine, Faculty of Medicine, University of Thessaly, 41110 Larissa, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1389","DOI":"10.1001\/jama.2020.3514","article-title":"Diagnosis and Management of Obstructive Sleep Apnea: A Review","volume":"323","author":"Gottlieb","year":"2020","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1152\/physrev.00043.2008","article-title":"Pathophysiology of sleep apnea","volume":"90","author":"Dempsey","year":"2010","journal-title":"Physiol. 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