{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T04:20:12Z","timestamp":1787804412393,"version":"build-2784847793"},"reference-count":40,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:00:00Z","timestamp":1787616000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008126","name":"Jeju National University Hospital","doi-asserted-by":"publisher","award":["2022-21"],"award-info":[{"award-number":["2022-21"]}],"id":[{"id":"10.13039\/501100008126","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2022-21"],"award-info":[{"award-number":["2022-21"]}],"id":[{"id":"https:\/\/ror.org\/05p64mb74","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background\/Objectives: We investigated the associations of severe vision impairment (SVI) with SARS-CoV-2 infection and COVID-19 outcomes using the nationwide K-COV-N database, which links Korea Disease Control and Prevention Agency SARS-CoV-2 testing records with National Health Insurance Service data. Methods: Adults aged \u226520 years with laboratory-confirmed SARS-CoV-2 infection and matched controls who either tested negative or were untested but had no documented SARS-CoV-2 infection between 8 October 2020, and 31 December 2021, were included. Pre-existing SVI was defined using an inclusive algorithm based on either a best-corrected visual acuity &lt;6\/60 in the better-seeing eye in the health-checkup database or legal SVI recorded in the National Disability Registration System before the COVID-19 observation period. Propensity score matching (1:30) was used to evaluate SARS-CoV-2 test positivity in the overall cohort and severe COVID-19 outcomes among infected individuals. Results: The study included 560,182 SARS-CoV-2-positive individuals and 1,677,364 matched controls. After adjustment, SVI was associated with a trend toward higher SARS-CoV-2 test positivity (adjusted odds ratio [aOR], 1.09; 95% confidence interval [CI], 0.99\u20131.20). Among infected individuals, SVI was associated with increased odds of severe COVID-19 illness (aOR, 3.05; 95% CI, 2.59\u20133.58) and COVID-19-related death (aOR, 1.39; 95% CI, 1.13\u20131.71), with stronger associations during the Delta variant period. Conclusions: These findings suggest that SVI is associated with poorer COVID-19 outcomes and may increase susceptibility to SARS-CoV-2 infection.<\/jats:p>","DOI":"10.3390\/jcm15176563","type":"journal-article","created":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T15:01:07Z","timestamp":1787670067000},"page":"6563","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Severe Vision Impairment and Its Association with COVID-19 Susceptibility, Severity, and Mortality: A Population-Based Cohort Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6037-8449","authenticated-orcid":false,"given":"Young Kook","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Seoul National University Hospital, Seoul 03080, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Su Hwan","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Preventive Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-7758-6850","authenticated-orcid":false,"given":"June Ho","family":"Lee","sequence":"additional","affiliation":[{"name":"Seoul National University College of Medicine, Seoul National University, Seoul 03080, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chae Young","family":"Oh","sequence":"additional","affiliation":[{"name":"Department of Statistics, Sungkyunkwan University, Seoul 03063, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6440-6718","authenticated-orcid":false,"given":"Hajoung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Statistics, Seoul National University, Seoul 08826, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-1816-6838","authenticated-orcid":false,"given":"Goneui","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Seoul National University Hospital, Seoul 03080, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8431-4768","authenticated-orcid":false,"given":"Sooyeon","family":"Choe","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Ajou University Hospital, Ajou University School of Medicine, Suwon 16499, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jieun","family":"Cheon","sequence":"additional","affiliation":[{"name":"Sociocultural Research Division, Jeonbuk Institute, Jeonju 55068, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4432-4894","authenticated-orcid":false,"given":"Hyung-Jin","family":"Yoon","sequence":"additional","affiliation":[{"name":"Medical Bigdata Research Center, Seoul National University College of Medicine, Seoul 03080, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4211-7971","authenticated-orcid":false,"given":"Ahnul","family":"Ha","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Jeju National University College of Medicine, Jeju-si 63243, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,25]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2021, September 25). 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