{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T05:14:00Z","timestamp":1780636440222,"version":"3.54.1"},"reference-count":76,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,5,19]],"date-time":"2021-05-19T00:00:00Z","timestamp":1621382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Zayed Univerity","award":["R20104"],"award-info":[{"award-number":["R20104"]}]},{"DOI":"10.13039\/501100004070","name":"Khalifa University","doi-asserted-by":"publisher","award":["Internal grant"],"award-info":[{"award-number":["Internal grant"]}],"id":[{"id":"10.13039\/501100004070","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Insufficient blood levels of the neurohormone vitamin D are associated with increased risk of COVID-19 severity and mortality. Despite the global rollout of vaccinations and promising preliminary results, the focus remains on additional preventive measures to manage COVID-19. Results conflict on vitamin D\u2019s plausible role in preventing and treating COVID-19. We examined the relation between vitamin D status and COVID-19 severity and mortality among the multiethnic population of the United Arab Emirates. Our observational study used data for 522 participants who tested positive for SARS-CoV-2 at one of the main hospitals in Abu Dhabi and Dubai. Only 464 of those patients were included for data analysis. Demographic and clinical data were retrospectively analyzed. Serum samples immediately drawn at the first hospital visit were used to measure serum 25-hydroxyvitamin D [25(OH)D] concentrations through automated electrochemiluminescence. Levels &lt; 12 ng\/mL were significantly associated with higher risk of severe COVID-19 infection and of death. Age was the only other independent risk factor, whereas comorbidities and smoking did not contribute to the outcomes upon adjustment. Sex of patients was not an important predictor for severity or death. Our study is the first conducted in the UAE to measure 25(OH)D levels in SARS-CoV-2-positive patients and confirm the association of levels &lt; 12 ng\/mL with COVID-19 severity and mortality.<\/jats:p>","DOI":"10.3390\/nu13051714","type":"journal-article","created":{"date-parts":[[2021,5,19]],"date-time":"2021-05-19T21:49:21Z","timestamp":1621460961000},"page":"1714","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":72,"title":["COVID-19 Disease Severity and Death in Relation to Vitamin D Status among SARS-CoV-2-Positive UAE Residents"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7141-1438","authenticated-orcid":false,"given":"Habiba","family":"AlSafar","sequence":"first","affiliation":[{"name":"Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates"},{"name":"Department of Biomedical Engineering, College of Engineering, Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates"},{"name":"Department of Genetics and Molecular Biology, College of Medicine and Health Sciences, Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1439-3285","authenticated-orcid":false,"given":"William B.","family":"Grant","sequence":"additional","affiliation":[{"name":"Sunlight, Nutrition and Health Research Center, P.O. Box 641603, San Francisco, CA 94164-1603, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6895-9280","authenticated-orcid":false,"given":"Rafiq","family":"Hijazi","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Statistics, College of Natural and Health Sciences, Zayed University, Abu Dhabi 144534, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1175-4145","authenticated-orcid":false,"given":"Maimunah","family":"Uddin","sequence":"additional","affiliation":[{"name":"Department of Pediatric Infectious Disease, Sheikh Khalifa Medical City, Abu Dhabi 51900, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nawal","family":"Alkaabi","sequence":"additional","affiliation":[{"name":"Department of Pediatric Infectious Disease, Sheikh Khalifa Medical City, Abu Dhabi 51900, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6639-3298","authenticated-orcid":false,"given":"Guan","family":"Tay","sequence":"additional","affiliation":[{"name":"Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates"},{"name":"Division of Psychiatry, Faculty of Health and Medical Sciences, University of Western Australia, Crawley, Western Australia, Australia"},{"name":"School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4665-6024","authenticated-orcid":false,"given":"Bassam","family":"Mahboub","sequence":"additional","affiliation":[{"name":"Dubai Health Authority, Rashid Hospital, Dubai, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1993-6656","authenticated-orcid":false,"given":"Fatme","family":"Al Anouti","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, College of Natural and Health Sciences, Zayed University, Abu Dhabi 144534, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hussein, T., L\u00f6ndahl, J., Thuresson, S., Alsved, M., Al-Hunaiti, A., Saksela, K., Aqel, H., Junninen, H., Mahura, A., and Kulmala, M. 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