{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T22:28:01Z","timestamp":1783636081618,"version":"3.55.0"},"reference-count":67,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,7,22]],"date-time":"2022-07-22T00:00:00Z","timestamp":1658448000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["19-15-00243-P"],"award-info":[{"award-number":["19-15-00243-P"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>There is increasing data regarding the association between vitamin D and COVID-19. This study aimed to reveal the alterations of vitamin D metabolism in the setting of COVID-19. We examined 119 adult COVID-19 inpatients and 44 apparently healthy adult individuals with similar serum 25OH-D3 levels as a reference group. The assessment included serum biochemical parameters (total calcium, albumin, phosphorus, creatinine), parathyroid hormone (PTH), vitamin D-binding protein (DBP), vitamin D metabolites (25OH-D3, 25OH-D2, 1,25(OH)2D3, 3-epi-25OH-D3, 24,25(OH)2D3 and D3) and free 25OH-D. COVID-19 patients had in general very low vitamin D levels (median 25OH-D3 equals 10.8 ng\/mL), accompanied by an increased production of the active vitamin D metabolite (1,25(OH)2D3), estimated as higher 1,25(OH)2D3 serum levels (61 [44; 81] vs. 40 [35; 50] pg\/mL, p &lt; 0.001) and lower 25OH-D3\/1,25(OH)2D3 ratio (175 [112; 260] vs. 272 [200; 433], p &lt; 0.001) which is presumably aimed at preventing hypocalcemia. Patients with COVID-19 also had elevated DBP (450 [386; 515] vs. 392 [311; 433] mg\/L, p &lt; 0.001) and low free 25OH-D levels (&lt;LoB vs. 3.9 [3.2; 4.4] pg\/mL, p &lt; 0.001). Follow-up assessment of the COVID-19 inpatients showed recovery of the observed changes. Overall, hospitalized patients with an acute course of COVID-19 have not only very low levels of 25OH-D but also profound abnormalities in the metabolism of vitamin D regardless of the clinical course of the disease. These alterations might exacerbate existing vitamin D deficiency and its negative impact.<\/jats:p>","DOI":"10.3390\/ph15080906","type":"journal-article","created":{"date-parts":[[2022,7,25]],"date-time":"2022-07-25T01:42:13Z","timestamp":1658713333000},"page":"906","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Impaired Vitamin D Metabolism in Hospitalized COVID-19 Patients"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7634-5457","authenticated-orcid":false,"given":"Alexandra","family":"Povaliaeva","sequence":"first","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6377-9056","authenticated-orcid":false,"given":"Viktor","family":"Bogdanov","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ekaterina","family":"Pigarova","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larisa","family":"Dzeranova","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nino","family":"Katamadze","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natalya","family":"Malysheva","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vitaliy","family":"Ioutsi","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larisa","family":"Nikankina","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liudmila","family":"Rozhinskaya","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natalia","family":"Mokrysheva","sequence":"additional","affiliation":[{"name":"Endocrinology Research Centre, 117292 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,22]]},"reference":[{"key":"ref_1","first-page":"11","article-title":"The origin, transmission and clinical therapies on coronavirus disease 2019 (COVID-19) outbreak\u2014An update on the status","volume":"7","author":"Guo","year":"2020","journal-title":"Mil. 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