{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T05:16:49Z","timestamp":1762492609488,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T00:00:00Z","timestamp":1762300800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004586","name":"FAPERJ","doi-asserted-by":"crossref","award":["E26\/210.272\/2024"],"award-info":[{"award-number":["E26\/210.272\/2024"]}],"id":[{"id":"10.13039\/501100004586","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Exertional oxygen desaturation (SpO2 \u2264 88%) during the six-minute walk test (6MWT) is a key prognostic marker in interstitial lung disease (ILD), yet access to the test is often limited in clinical practice. Developing simple, bedside tools to identify patients at risk may support early risk stratification and guide clinical decision-making. Methods: We conducted a retrospective, real-world cohort study in a tertiary referral center between January 2024 and July 2025, including 150 patients, of whom 67.33% (101 patients) were using supplemental oxygen. Clinical and physiological data collected within 30 days of the 6MWT were analyzed. The primary outcome was exertional hypoxemia, defined as peripheral oxygen saturation (SpO2) \u2264 88% at the end of the test. Four predictive approaches were evaluated: multivariable logistic regression, stepwise logistic regression, and a simplified clinical score (0\u20133). The simplified score assigned one point for each of the following: forced vital capacity (FVC) \u2264 61% predicted, diffusing capacity for carbon monoxide (DLCO) \u2264 53% predicted, and presence of chronic cough. Model performance was assessed by receiver operating characteristic (ROC) curves, sensitivity, specificity, predictive values, and risk stratification. Results: The simplified score demonstrated robust discriminative performance, comparable to more complex statistical models, with high sensitivity and acceptable specificity. A threshold of \u22652.0 points identified patients at high risk for exertional desaturation with 100% sensitivity and 0.66 specificity. Observed desaturation risk increased progressively across score categories: 17.1% for scores 0\u20131 (low risk), 58.6% for score 2 (intermediate risk), and 95.1% for score 3 (high risk). Conclusions: Compared with multivariable models, the simplified 0\u20133 clinical score\u2014based on widely available variables (FVC \u2264 61%, DLCO \u2264 53%, and chronic cough)\u2014maintained similar predictive performance (AUC 0.82) with greater operational simplicity. Owing to its high sensitivity and bedside applicability, it represents a promising screening tool for identifying patients at high risk of exertional desaturation, particularly when the 6MWT is unavailable.<\/jats:p>","DOI":"10.3390\/jcm14217858","type":"journal-article","created":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T17:06:06Z","timestamp":1762362366000},"page":"7858","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Simplified Three-Item Clinical Score to Identify Exertional Hypoxemia in Fibrotic Interstitial Lung Disease: A Real-World Cohort Study"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5071-6045","authenticated-orcid":false,"given":"Rogerio","family":"Rufino","sequence":"first","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1332-1690","authenticated-orcid":false,"given":"Isabela Tamiozzo","family":"Serpa","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leonardo","family":"Palermo","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Bessa","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6325-2844","authenticated-orcid":false,"given":"Bruno","family":"Rangel","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mariana","family":"Lopes","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8598-4878","authenticated-orcid":false,"given":"Agnaldo Jos\u00e9","family":"Lopes","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mariana Costa","family":"Rufino","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, S\u00e3o Paulo University, S\u00e3o Paulo 01246-903, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6785-0753","authenticated-orcid":false,"given":"Cl\u00e1udia Henrique da","family":"Costa","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anamelia Costa","family":"Faria","sequence":"additional","affiliation":[{"name":"Department of Thoracic Diseases, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro 20551-030, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e121","DOI":"10.1164\/rccm.202009-3608ST","article-title":"Home Oxygen Therapy for Adults with Chronic Lung Disease. 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