{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T23:07:53Z","timestamp":1785539273898,"version":"3.56.0"},"reference-count":65,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,14]],"date-time":"2021-01-14T00:00:00Z","timestamp":1610582400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Little information is available on the beneficial effects of cholecalciferol treatment in comorbid patients hospitalized for COVID-19. The aim of this study was to retrospectively examine the clinical outcome of patients receiving in-hospital high-dose bolus cholecalciferol. Patients with a positive diagnosis of SARS-CoV-2 and overt COVID-19, hospitalized from 15 March to 20 April 2020, were considered. Based on clinical characteristics, they were supplemented (or not) with 400,000 IU bolus oral cholecalciferol (200,000 IU administered in two consecutive days) and the composite outcome (transfer to intensive care unit; ICU and\/or death) was recorded. Ninety-one patients (aged 74 \u00b1 13 years) with COVID-19 were included in this retrospective study. Fifty (54.9%) patients presented with two or more comorbid diseases. Based on the decision of the referring physician, 36 (39.6%) patients were treated with vitamin D. Receiver operating characteristic curve analysis revealed a significant predictive power of the four variables: (a) low (&lt;50 nmol\/L) 25(OH) vitamin D levels, (b) current cigarette smoking, (c) elevated D-dimer levels (d) and the presence of comorbid diseases, to explain the decision to administer vitamin D (area under the curve = 0.77, 95% CI: 0.67\u20130.87, p &lt; 0.0001). Over the follow-up period (14 \u00b1 10 days), 27 (29.7%) patients were transferred to the ICU and 22 (24.2%) died (16 prior to ICU and six in ICU). Overall, 43 (47.3%) patients experienced the combined endpoint of transfer to ICU and\/or death. Logistic regression analyses revealed that the comorbidity burden significantly modified the effect of vitamin D treatment on the study outcome, both in crude (p = 0.033) and propensity score-adjusted analyses (p = 0.039), so the positive effect of high-dose cholecalciferol on the combined endpoint was significantly amplified with increasing comorbidity burden. This hypothesis-generating study warrants the formal evaluation (i.e., clinical trial) of the potential benefit that cholecalciferol can offer in these comorbid COVID-19 patients.<\/jats:p>","DOI":"10.3390\/nu13010219","type":"journal-article","created":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T01:33:29Z","timestamp":1610674409000},"page":"219","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":64,"title":["Effectiveness of In-Hospital Cholecalciferol Use on Clinical Outcomes in Comorbid COVID-19 Patients: A Hypothesis-Generating Study"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0796-9749","authenticated-orcid":false,"given":"Sandro","family":"Giannini","sequence":"first","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4039-1160","authenticated-orcid":false,"given":"Giovanni","family":"Passeri","sequence":"additional","affiliation":[{"name":"Unit of Clinica e Terapia Medica, Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Tripepi","sequence":"additional","affiliation":[{"name":"National Research Council (CNR), Institute of Clinical Physiology (IFC), Clinical Epidemiology of Renal Diseases and Hypertension, Ospedali Riuniti, 89124 Reggio Calabria, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefania","family":"Sella","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9478-4851","authenticated-orcid":false,"given":"Maria","family":"Fusaro","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"},{"name":"National Research Council (CNR), Institute of Clinical Physiology (IFC), 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gaetano","family":"Arcidiacono","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marco Onofrio","family":"Torres","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Michielin","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tancredi","family":"Prandini","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valeria","family":"Baffa","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Aghi","sequence":"additional","affiliation":[{"name":"Clinica Medica 1, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6942-7147","authenticated-orcid":false,"given":"Colin Gerard","family":"Egan","sequence":"additional","affiliation":[{"name":"CE Medical Writing, 56021 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Brigo","sequence":"additional","affiliation":[{"name":"Internal Medicine, Department of Medicine, University Hospital AOUI, 37134 Verona, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Zaninotto","sequence":"additional","affiliation":[{"name":"Laboratory Medicine Unit, Department of Medicine, University of Padova, 35128 Padova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mario","family":"Plebani","sequence":"additional","affiliation":[{"name":"Laboratory Medicine Unit, Department of Medicine, University of Padova, 35128 Padova, 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