{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T22:27:50Z","timestamp":1783636070061,"version":"3.55.0"},"reference-count":37,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T00:00:00Z","timestamp":1621296000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T00:00:00Z","timestamp":1621296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Infect Dis"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>A protective effect of vitamin D against COVID-19 infection is under investigation. We aimed to analyze the effect of vitamin D sufficiency on the clinical outcomes of patients infected with COVID-19.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>In this cross-sectional study we analyzed the vitamin D levels of COVID-19 patients who were admitted to Razi Hospital (an infectious disease referral center in Mazandaran province in northern Iran) from February to March 2020. Overall, a cutoff point of 30\u2009ng\/mL was used for the definition of vitamin D sufficiency.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>One hundred fifty-three patients were analyzed in this study who had laboratory documentation of a 25(OH) D level at the time of hospitalization. The vitamin D levels of the patients were 27.19\u2009\u00b1\u200920.17\u2009ng\/mL. In total, 62.7% (<jats:italic>n<\/jats:italic>\u2009=\u200996) of the patients had a 25(OH) D level of less than 30\u2009ng\/mL and 37.25% (<jats:italic>n<\/jats:italic>\u2009=\u200957) had a 25(OH) D level of more than 30\u2009ng\/mL. In total, 49% (<jats:italic>n<\/jats:italic>\u2009=\u200975) of the patients suffered from at least one underlying disease. The univariate and multivariable regression showed that vitamin D sufficiency was not associated with a statistically significant lower risk of adverse clinical outcomes of COVID-19 such as duration of hospitalization and severity of infection (<jats:italic>P<\/jats:italic>\u2009&gt;\u20090.05).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Sufficient vitamin D levels were not found to be protective against adverse clinical outcomes in patients infected with COVID-19. Chronic disorders in COVID-19 patients were found to have greater relevance than vitamin D levels in determining the adverse outcomes of the infection. Further studies are needed to determine the role of vitamin D level in predicting the outcomes of COVID-19 infection.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12879-021-06168-7","type":"journal-article","created":{"date-parts":[[2021,6,4]],"date-time":"2021-06-04T09:21:56Z","timestamp":1622798516000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Lack of association between vitamin D insufficiency and clinical outcomes of patients with COVID-19 infection"],"prefix":"10.1186","volume":"21","author":[{"given":"Alireza","family":"Davoudi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Narges","family":"Najafi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohsen","family":"Aarabi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Atefeh","family":"Tayebi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roja","family":"Nikaeen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hamideh","family":"Izadyar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zahra","family":"Salar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leila","family":"Delavarian","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Narges","family":"Vaseghi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zahra","family":"Daftarian","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fatemeh","family":"Ahangarkani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,5,18]]},"reference":[{"key":"6168_CR1","doi-asserted-by":"publisher","unstructured":"Grant WB, Lahore H, McDonnell SL, Baggerly CA, French CB, Aliano JL, Bhattoa HP: Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths. 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In addition, written informed consent was obtained from all subjects or, for subjects under the age of 18, from a parent and\/or legal guardian. In this study all applied methods were carried out in accordance with relevant guidelines and regulations.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"450"}}