The effect of Vitamin D levels on the course of COVID-19 in hospitalized patients – a 1-year prospective cohort study

DOI record: { "DOI": "10.12688/f1000research.131730.1", "ISSN": [ "2046-1402" ], "URL": "http://dx.doi.org/10.12688/f1000research.131730.1", "abstract": "<ns4:p>Background: The aim of the current study was to assess the patients with COVID-19 and the impact of vitamin D supplementation on the course of COVID-19. </ns4:p><ns4:p> Methods: This prospective cohort study included patients hospitalized due to COVID-19 between December 2020 and December 2021. Patients' demographic, clinical, and laboratory parameters were analysed.  </ns4:p><ns4:p> Results: 301 participants were enrolled in the study. 46 (15,3%) had moderate, and 162 (53,8%) had severe COVID-19. 14 (4,7%) patients died, and 30 (10,0%) were admitted to the ICU due to disease worsening. The majority needed oxygen therapy (n=224; 74,4%). Average vitamin 25(OH)D3 levels were below optimal at the admittance, and vitamin D deficiency was detected in 205 individuals. More male patients were suffering from vitamin D deficiency. Patients with the more severe disease showed lower levels of vitamin 25(OH)D3 in their blood. The most severe group of patients had more symptoms that lasted significantly longer with progressing disease severity. This group of patients also suffered from more deaths, ICU admissions, and treatments with dexamethasone, remdesivir, and oxygen. </ns4:p><ns4:p> Conclusion: Patients with the severe course of COVID-19 were shown to have increased inflammatory parameters, increased mortality, and higher incidence of vitamin D deficiency. The results suggest that the vitamin D deficiency might represent a significant risk factor for a severe course of COVID-19.</ns4:p>", "assertion": [ { "URL": "https://f1000research.com/articles/12-254/v1#article-reports", "group": { "label": "Current Referee Status", "name": "current-referee-status" }, "label": "Referee status", "name": "referee-status", "order": 0, "value": "Awaiting Peer Review" }, { "label": "Grant Information", "name": "grant-information", "order": 0, "value": "The author(s) declared that no grants were involved in supporting this work" }, { "label": "Copyright", "name": "copyright-info", "order": 0, "value": "This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited." } ], "author": [ { "affiliation": [], "family": "Siuka", "given": "Darko", "sequence": "first" }, { "affiliation": [], "family": "Saletinger", "given": "Rajko", "sequence": "additional" }, { "affiliation": [], "family": "Uršič", "given": "Jure", "sequence": "additional" }, { "affiliation": [], "family": "Jevnikar", "given": "Kristina", "sequence": "additional" }, { "affiliation": [], "family": "Janša", "given": "Rado", "sequence": "additional" }, { "ORCID": "http://orcid.org/0000-0002-9653-9830", "affiliation": [], "authenticated-orcid": false, "family": "Štubljar", "given": "David", "sequence": "additional" }, { "ORCID": "http://orcid.org/0000-0002-1839-2415", "affiliation": [], "authenticated-orcid": false, "family": "Osredkar", "given": "Joško", "sequence": "additional" } ], "container-title": "F1000Research", "container-title-short": "F1000Res", "content-domain": { "crossmark-restriction": false, "domain": [ "f1000research.com" ] }, "created": { "date-parts": [ [ 2023, 3, 9 ] ], "date-time": "2023-03-09T14:26:41Z", "timestamp": 1678372001000 }, "deposited": { "date-parts": [ [ 2023, 3, 9 ] ], "date-time": "2023-03-09T14:26:49Z", "timestamp": 1678372009000 }, "indexed": { "date-parts": [ [ 2023, 3, 10 ] ], "date-time": "2023-03-10T05:46:39Z", "timestamp": 1678427199389 }, "is-referenced-by-count": 0, "issued": { "date-parts": [ [ 2023, 3, 9 ] ] }, "language": "en", "license": [ { "URL": "http://creativecommons.org/licenses/by/4.0/", "content-version": "tdm", "delay-in-days": 0, "start": { "date-parts": [ [ 2023, 3, 9 ] ], "date-time": "2023-03-09T00:00:00Z", "timestamp": 1678320000000 } } ], "link": [ { "URL": "https://f1000research.com/articles/12-254/v1/xml", "content-type": "application/xml", "content-version": "vor", "intended-application": "text-mining" }, { "URL": "https://f1000research.com/articles/12-254/v1/pdf", "content-type": "application/pdf", "content-version": "vor", "intended-application": "text-mining" }, { "URL": "https://f1000research.com/articles/12-254/v1/iparadigms", "content-type": "unspecified", "content-version": "vor", "intended-application": "similarity-checking" } ], "member": "2560", "original-title": [], "page": "254", "prefix": "10.12688", "published": { "date-parts": [ [ 2023, 3, 9 ] ] }, "published-online": { "date-parts": [ [ 2023, 3, 9 ] ] }, "publisher": "F1000 Research Ltd", "reference": [ { "article-title": "The COVID-19 Pandemic, Seasons and the Vitamin D Laboratory Strategy.", "author": "D Siuka", "first-page": "182-189", "journal-title": "International Journal of Sciences: Basic and Applied Research (IJSBAR).", "key": "ref1", "volume": "56", "year": "2021" }, { "article-title": "Factors influencing the seasonal patterns of infectious diseases.", "author": "A Fares", "first-page": "128-132", "journal-title": "Int. 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