{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:29:42Z","timestamp":1760059782694,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,7,9]],"date-time":"2025-07-09T00:00:00Z","timestamp":1752019200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Thammasat University, Thailand","award":["TUFT 30\/2565"],"award-info":[{"award-number":["TUFT 30\/2565"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medical Sciences"],"abstract":"<jats:p>Background: Patients with mild coronavirus disease 2019 (COVID-19) are usually managed in an outpatient setting. Pulmonary functions in this setting have not been explored. This study aimed to determine abnormal lung functions in COVID-19 patients under a home isolation program. Methods: A prospective study was conducted in asymptomatic or mild COVID-19 patients with normal chest radiographs at two medical centers in Thailand. Spirometry data, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), forced expiratory flow at 25\u201375% of FVC (FEF25\u201375), and bronchodilator responsiveness (BDR), were collected. Spirometry was performed after disease resolution at baseline and 3-month follow-up. Abnormal lung functions were classified into airway obstruction, restrictive defect, mixed defect, small airway disease, and BDR. Results: A total of 250 patients (58% female) were included. The mean age was 37.4 \u00b1 15.2 years. Asymptomatic patients accounted for 7.6%. Common symptoms included fever (55.6%) and cough (60.0%). Abnormal lung functions were observed in 28.4% of patients, with a restrictive lung pattern (14.4%), airway obstruction (4.8%), mixed defect (0.4%), small airway disease (8.4%), and BDR (2.8%). Significant changes from baseline were noted in FVC (1.21%), FEV1\/FVC (\u22121.51%predicted), PEF (0.06%), and FEF25\u201375 (\u22122.76%). Logistic regression analysis indicated that a higher body mass index was associated with a lower risk of abnormal lung function. Conclusions: Ventilatory defects were observed in one-third of patients with mild COVID-19 who did not require hospitalization, mainly presenting as restrictive patterns and small airway disease. Even mild cases may have residual pulmonary impairment, warranting further long-term studies.<\/jats:p>","DOI":"10.3390\/medsci13030088","type":"journal-article","created":{"date-parts":[[2025,7,11]],"date-time":"2025-07-11T15:19:31Z","timestamp":1752247171000},"page":"88","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pulmonary Function Among COVID-19 Patients in Home Isolation Program"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2462-9471","authenticated-orcid":false,"given":"Narongkorn","family":"Saiphoklang","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"},{"name":"Medical Diagnostics Unit, Thammasat University Hospital, Pathum Thani 12120, Thailand"},{"name":"Center of Excellence for Allergy, Asthma and Pulmonary Diseases, Thammasat University Hospital, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1207-2189","authenticated-orcid":false,"given":"Pitchayapa","family":"Ruchiwit","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Apichart","family":"Kanitsap","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pichaya","family":"Tantiyavarong","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"},{"name":"Department of Clinical Epidemiology, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8655-7154","authenticated-orcid":false,"given":"Pasitpon","family":"Vatcharavongvan","sequence":"additional","affiliation":[{"name":"Department of Community Medicine and Family Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Srimuang","family":"Palungrit","sequence":"additional","affiliation":[{"name":"Department of Community Medicine and Family Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kanyada","family":"Leelasittikul","sequence":"additional","affiliation":[{"name":"Medical Diagnostics Unit, Thammasat University Hospital, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Apiwat","family":"Pugongchai","sequence":"additional","affiliation":[{"name":"Medical Diagnostics Unit, Thammasat University Hospital, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0610-8242","authenticated-orcid":false,"given":"Orapan","family":"Poachanukoon","sequence":"additional","affiliation":[{"name":"Center of Excellence for Allergy, Asthma and Pulmonary Diseases, Thammasat University Hospital, Pathum Thani 12120, Thailand"},{"name":"Department of Pediatrics, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,9]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2024, April 01). 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