{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:28:55Z","timestamp":1760149735136,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T00:00:00Z","timestamp":1692921600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Swiss National Science Foundation","award":["160072","185592","2018DR108"],"award-info":[{"award-number":["160072","185592","2018DR108"]}]},{"name":"Swiss Personalized Health Network","award":["160072","185592","2018DR108"],"award-info":[{"award-number":["160072","185592","2018DR108"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>(1) Background: SARS-COV2 infection has a clinical spectrum ranging from asymptomatic infection to COVID-19 with acute respiratory distress syndrome (ARDS). Although vitamin D deficiency is often found in patients with ARDS, its role in COVID-19 is not clear. The aim of this study was to explore a possible association between serum 25-hydroxyvitamin D levels and the severity of COVID-19 in hospitalised patients. (2) Methods: In this retrospective observational study, we analysed data from 763 patients hospitalised for COVID-19 in 2020 and 2021. Patients were included in the study if serum 25-hydroxyvitamin D was assessed 30 days before or after hospital admission. Vitamin D deficiency was defined as &lt;50 nmol\/L (&lt;20 ng\/mL). The primary outcome was COVID-19 severity. (3) Results: The overall median serum 25-hydroxyvitamin D level was 54 nmol\/L (IQR 35\u201376); 47% of the patients were vitamin D deficient. Most patients had mild to moderate COVID-19 and no differences were observed between vitamin D deficient and non-deficient patients (81% vs. 84% of patients, respectively p = 0.829). (4) Conclusion: No association was found between serum 25-hydroxyvitamin D levels and COVID-19 severity in this large observational study conducted over 2 years of the pandemic.<\/jats:p>","DOI":"10.3390\/jcm12175520","type":"journal-article","created":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T08:42:20Z","timestamp":1692952940000},"page":"5520","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Is Serum 25-Hydroxyvitamin D Level Associated with Severity of COVID-19? A Retrospective Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-8505-6290","authenticated-orcid":false,"given":"Munachimso Kizito","family":"Mbata","sequence":"first","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"},{"name":"Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mireille","family":"Hunziker","sequence":"additional","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"},{"name":"Center for Rehabilitation and Geriatrics, Cantonal Hospital Baselland, Gemeindeholzweg, 4101 Bruderholz, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anja","family":"Makhdoomi","sequence":"additional","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giorgia","family":"L\u00fcthi-Corridori","sequence":"additional","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"},{"name":"Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8605-1893","authenticated-orcid":false,"given":"Maria","family":"Boesing","sequence":"additional","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"},{"name":"Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"St\u00e9phanie","family":"Giezendanner","sequence":"additional","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00fcrgen","family":"Muser","sequence":"additional","affiliation":[{"name":"Central Laboratories, Cantonal Hospital Baselland, Rheinstrasse 26, 4410 Liestal, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anne B.","family":"Leuppi-Taegtmeyer","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland"},{"name":"Hospital Pharmacy, Cantonal Hospital Baselland, Rheinstrasse 26, 4410 Liestal, Switzerland"},{"name":"Department of Patient Safety, Medical Directorate, University Hospital Basel, Schanzenstrasse 55, 4056 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5554-0675","authenticated-orcid":false,"given":"J\u00f6rg D.","family":"Leuppi","sequence":"additional","affiliation":[{"name":"Cantonal Hospital Baselland, University Center of Internal Medicine, Rheinstrasse 26, 4410 Liestal, Switzerland"},{"name":"Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,25]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2020). Coronavirus Disease 2019 (COVID-19) Situation Report\u201451, World Health Organization."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1056\/NEJMoa2001017","article-title":"A Novel Coronavirus from Patients with Pneumonia in China, 2019","volume":"382","author":"Zhu","year":"2020","journal-title":"N. Engl. J. Med."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Gorbalenya, A.E., Baker, S.C., Baric, R.S., de Groot, R.J., Drosten, C., Gulyaeva, A.A., Haagmans, B.L., Lauber, C., Leontovich, A.M., and Neuman, B.W. (2020). Severe acute respiratory syndrome-related coronavirus: The species and its viruses\u2014A statement of the Coronavirus Study Group. bioRxiv.","DOI":"10.1101\/2020.02.07.937862"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3089","DOI":"10.1016\/j.clnu.2021.03.001","article-title":"Vitamin D deficiency in critically ill COVID-19 ARDS patients","volume":"41","author":"Notz","year":"2021","journal-title":"Clin. Nutr."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1016\/S0140-6736(20)30211-7","article-title":"Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: A descriptive study","volume":"395","author":"Chen","year":"2020","journal-title":"Lancet"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1186\/s13756-020-00875-7","article-title":"Nosocomial transmission and outbreaks of coronavirus disease 2019: The need to protect both patients and healthcare workers","volume":"10","author":"Abbas","year":"2021","journal-title":"Antimicrob. Resist. Infect. Control"},{"key":"ref_7","unstructured":"John Hopkins University & Medicine (2021, December 16). Mortality Analysis. Available online: https:\/\/coronavirus.jhu.edu\/data\/mortality."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"w20572","DOI":"10.4414\/smw.2021.20572","article-title":"Temporal trends of COVID-19 related in-hospital mortality and demographics in Switzerland\u2014A retrospective single centre cohort study","volume":"151","author":"Diebold","year":"2021","journal-title":"Swiss Med. Wkly."},{"key":"ref_9","unstructured":"Federal Office of Public Health FOPH (2021, December 17). COVID-19 Switzerland, Information on the Current Situation, as of 4 June 2021. Available online: https:\/\/www.covid19.admin.ch\/de\/epidemiologic\/case?demoView=graph."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2062","DOI":"10.1172\/JCI29449","article-title":"Resurrection of vitamin D deficiency and rickets","volume":"116","author":"Holick","year":"2006","journal-title":"J. Clin. Investig."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1056\/NEJMra070553","article-title":"Vitamin D deficiency","volume":"357","author":"Holick","year":"2007","journal-title":"N. Engl. J. Med."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Hribar, C.A., Cobbold, P.H., and Church, F.C. (2020). Potential Role of Vitamin D in the Elderly to Resist COVID-19 and to Slow Progression of Parkinson\u2019s Disease. Brain. Sci., 10.","DOI":"10.3390\/brainsci10050284"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e2032","DOI":"10.1002\/rmv.2032","article-title":"The interplay between vitamin D and viral infections","volume":"29","author":"Shokri","year":"2019","journal-title":"Rev. Med. Virol."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Grant, W.B., Lahore, H., McDonnell, S.L., Baggerly, C.A., French, C.B., Aliano, J.L., and Bhattoa, H.P. (2020). Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths. Nutrients, 12.","DOI":"10.20944\/preprints202003.0235.v2"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1186\/s12937-021-00744-y","article-title":"Low vitamin D levels do not aggravate COVID-19 risk or death, and vitamin D supplementation does not improve outcomes in hospitalized patients with COVID-19: A meta-analysis and GRADE assessment of cohort studies and RCTs","volume":"20","author":"Chen","year":"2021","journal-title":"Nutr. J."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"e2019722","DOI":"10.1001\/jamanetworkopen.2020.19722","article-title":"Association of Vitamin D Status and Other Clinical Characteristics with COVID-19 Test Results","volume":"3","author":"Meltzer","year":"2020","journal-title":"JAMA Netw. Open"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Mendy, A., Apewokin, S., Wells, A.A., and Morrow, A.L. (2020). Factors Associated with Hospitalization and Disease Severity in a Racially and Ethnically Diverse Population of COVID-19 Patients. medRxiv.","DOI":"10.1101\/2020.06.25.20137323"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Radujkovic, A., Hippchen, T., Tiwari-Heckler, S., Dreher, S., Boxberger, M., and Merle, U. (2020). Vitamin D Deficiency and Outcome of COVID-19 Patients. Nutrients, 12.","DOI":"10.3390\/nu12092757"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"545","DOI":"10.1007\/s00394-020-02372-4","article-title":"Vitamin D and COVID-19 infection and mortality in UK Biobank","volume":"60","author":"Hastie","year":"2021","journal-title":"Eur. J. Nutr."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"875","DOI":"10.1016\/j.mayocp.2021.01.001","article-title":"Vitamin D Status Is Associated with In-Hospital Mortality and Mechanical Ventilation: A Cohort of COVID-19 Hospitalized Patients","volume":"96","author":"Angelidi","year":"2021","journal-title":"Mayo Clin. Proc."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1007\/s12603-020-1479-0","article-title":"Impact of Serum 25(OH) Vitamin D Level on Mortality in Patients with COVID-19 in Turkey","volume":"25","author":"Karahan","year":"2021","journal-title":"J. Nutr. Health Aging"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/j.eprac.2021.02.013","article-title":"Association of Vitamin D Status with Hospital Morbidity and Mortality in Adult Hospitalized Patients with COVID-19","volume":"27","author":"Charoenngam","year":"2021","journal-title":"Endocr. Pract."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"AlSafar, H., Grant, W.B., Hijazi, R., Uddin, M., Alkaabi, N., Tay, G., Mahboub, B., and Al Anouti, F. (2021). COVID-19 Disease Severity and Death in Relation to Vitamin D Status among SARS-CoV-2-Positive UAE Residents. Nutrients, 13.","DOI":"10.3390\/nu13051714"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"765","DOI":"10.1007\/s40618-020-01370-x","article-title":"Vitamin D deficiency as a predictor of poor prognosis in patients with acute respiratory failure due to COVID-19","volume":"44","author":"Carpagnano","year":"2021","journal-title":"J. Endocrinol. Investig."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1093\/ajcp\/aqaa252","article-title":"Serum 25(OH)D Level on Hospital Admission Associated with COVID-19 Stage and Mortality","volume":"155","author":"Herroelen","year":"2021","journal-title":"Am. J. Clin. Pathol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1315","DOI":"10.1016\/j.dsx.2020.07.021","article-title":"Corrigendum to \u201cVitamin D concentrations and COVID-19 infection in UK Biobank\u201d [Diabetes Metabol Syndr: Clin Res Rev 2020 14 (4) 561\u20135]","volume":"14","author":"Hastie","year":"2020","journal-title":"Diabetes Metab. Syndr."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"451","DOI":"10.1093\/pubmed\/fdaa095","article-title":"Greater risk of severe COVID-19 in Black, Asian and Minority Ethnic populations is not explained by cardiometabolic, socioeconomic or behavioural factors, or by 25(OH)-vitamin D status: Study of 1326 cases from the UK Biobank","volume":"42","author":"McCracken","year":"2020","journal-title":"J. Public Health"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1136\/thoraxjnl-2014-206680","article-title":"Vitamin D deficiency contributes directly to the acute respiratory distress syndrome (ARDS)","volume":"70","author":"Dancer","year":"2015","journal-title":"Thorax"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1186\/s13063-022-06016-2","article-title":"High-dose vitamin D substitution in patients with COVID-19: Study protocol for a randomized, double-blind, placebo-controlled, multi-center study-VitCov Trial","volume":"23","author":"Jaun","year":"2022","journal-title":"Trials"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Bergman, P., Lindh, A.U., Bjorkhem-Bergman, L., and Lindh, J.D. (2013). Vitamin D and Respiratory Tract Infections: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0065835"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Sabico, S., Enani, M.A., Sheshah, E., Aljohani, N.J., Aldisi, D.A., Alotaibi, N.H., Alshingetti, N., Alomar, S.Y., Alnaami, A.M., and Amer, O.E. (2021). Effects of a 2-Week 5000 IU versus 1000 IU Vitamin D3 Supplementation on Recovery of Symptoms in Patients with Mild to Moderate Covid-19: A Randomized Clinical Trial. Nutrients, 13.","DOI":"10.3390\/nu13072170"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1520","DOI":"10.1001\/jama.2014.13204","article-title":"Effect of high-dose vitamin D3 on hospital length of stay in critically ill patients with vitamin D deficiency: The VITdAL-ICU randomized clinical trial","volume":"312","author":"Amrein","year":"2014","journal-title":"JAMA"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e192","DOI":"10.1016\/S1473-3099(20)30483-7","article-title":"A minimal common outcome measure set for COVID-19 clinical research","volume":"20","author":"Marshall","year":"2020","journal-title":"Lancet Infect. Dis."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"103208","DOI":"10.1016\/j.jbi.2019.103208","article-title":"The REDCap consortium: Building an international community of software platform partners","volume":"95","author":"Harris","year":"2019","journal-title":"J. Biomed. Inform."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.jbi.2008.08.010","article-title":"Research electronic data capture (REDCap)\u2014A metadata-driven methodology and workflow process for providing translational research informatics support","volume":"42","author":"Harris","year":"2009","journal-title":"J. Biomed. Inform."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"5615","DOI":"10.1007\/s00216-015-8733-z","article-title":"A candidate reference measurement procedure for quantifying serum concentrations of 25-hydroxyvitamin D(3) and 25-hydroxyvitamin D(2) using isotope-dilution liquid chromatography-tandem mass spectrometry","volume":"407","author":"Mineva","year":"2015","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.annepidem.2007.12.001","article-title":"Vitamin D status: Measurement, interpretation, and clinical application","volume":"19","author":"Holick","year":"2009","journal-title":"Ann. Epidemiol."},{"key":"ref_38","unstructured":"Bess Dawson-Hughes, M. (2023, August 16). Patient Education: Vitamin D Deficiency (Beyond the Basics). Available online: https:\/\/www.uptodate.com\/contents\/vitamin-d-deficiency-beyond-the-basics."},{"key":"ref_39","unstructured":"Brigham and Women\u2019s Hospital (2022, June 15). COVID Protocols\u2014Treatments. Available online: https:\/\/covidprotocols.org\/en\/chapters\/treatments\/."},{"key":"ref_40","unstructured":"National Institutes of Health (2022, June 15). COVID-19 Treatment Guidelines\u2014Therapies, Available online: https:\/\/www.covid19treatmentguidelines.nih.gov\/therapies\/."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"e1343","DOI":"10.1210\/clinem\/dgaa733","article-title":"Vitamin D Status in Hospitalized Patients with SARS-CoV-2 Infection","volume":"106","author":"Hernandez","year":"2021","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"390","DOI":"10.1016\/j.ijid.2020.08.018","article-title":"Nutritional status of patients with COVID-19","volume":"100","author":"Im","year":"2020","journal-title":"Int. J. Infect. Dis."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Georgoulis, M., Kontogianni, M.D., Kechribari, I., Tenta, R., Fragopoulou, E., Lamprou, K., Perraki, E., Vagiakis, E., and Yiannakouris, N. (2023). Associations between serum vitamin D status and the cardiometabolic profile of patients with obstructive sleep apnea. Hormones.","DOI":"10.1183\/23120541.sleepandbreathing-2023.63"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Drame, M., Cofais, C., Hentzien, M., Proye, E., Coulibaly, P.S., Demoustier-Tampere, D., Destailleur, M.H., Lotin, M., Cantagrit, E., and Cebille, A. (2021). Relation between Vitamin D and COVID-19 in Aged People: A Systematic Review. Nutrients, 13.","DOI":"10.3390\/nu13041339"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1636","DOI":"10.1093\/advances\/nmab012","article-title":"Association of Vitamin D Status with SARS-CoV-2 Infection or COVID-19 Severity: A Systematic Review and Meta-analysis","volume":"12","author":"Kazemi","year":"2021","journal-title":"Adv. Nutr."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"598","DOI":"10.1093\/ajcn\/nqab151","article-title":"Influence of vitamin D status on hospital length of stay and prognosis in hospitalized patients with moderate to severe COVID-19: A multicenter prospective cohort study","volume":"114","author":"Reis","year":"2021","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1498","DOI":"10.1038\/s41430-020-0558-y","article-title":"Vitamin D deficiency 2.0: An update on the current status worldwide","volume":"74","author":"Amrein","year":"2020","journal-title":"Eur. J. Clin. Nutr."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"899300","DOI":"10.3389\/fnut.2022.899300","article-title":"Vitamin D Intake and Factors Associated with Self-Reported Vitamin D Deficiency Among US Adults: A 2021 Cross-Sectional Study","volume":"9","author":"Andrade","year":"2022","journal-title":"Front. Nutr."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1002\/jbmr.2010","article-title":"Vitamin D supplementation in young White and African American women","volume":"29","author":"Gallagher","year":"2014","journal-title":"J. Bone Miner. Res."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"729","DOI":"10.1002\/jcp.22004","article-title":"Upregulation of MMP-9 production by TNFalpha in keratinocytes and its attenuation by vitamin D","volume":"222","author":"Ravid","year":"2010","journal-title":"J. Cell Physiol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"692","DOI":"10.1165\/rcmb.2009-0250OC","article-title":"The human cathelicidin LL-37 preferentially promotes apoptosis of infected airway epithelium","volume":"43","author":"Barlow","year":"2010","journal-title":"Am. J. Respir. Cell Mol. Biol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"1069","DOI":"10.1084\/jem.192.7.1069","article-title":"Ll-37, the Neutrophil Granule\u2013And Epithelial Cell\u2013Derived Cathelicidin, Utilizes Formyl Peptide Receptor\u2013Like 1 (Fprl1) as a Receptor to Chemoattract Human Peripheral Blood Neutrophils, Monocytes, and T Cells","volume":"192","author":"Yang","year":"2000","journal-title":"J. Exp. Med."},{"key":"ref_53","unstructured":"Syed Mohd, S.S., Mishra, A., and Ashraf, M.Z. (2021). Vitamin D, IntechOpen."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"3167","DOI":"10.2147\/JIR.S363840","article-title":"The Role of Vitamin D in Immune System and Inflammatory Bowel Disease","volume":"15","author":"Wu","year":"2022","journal-title":"J. Inflamm. Res."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"70","DOI":"10.5217\/ir.2018.00022","article-title":"Vitamin D deficiency is associated with disease activity in patients with Crohn\u2019s disease","volume":"17","author":"Ko","year":"2019","journal-title":"Intest. Res."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1177\/0148607110381267","article-title":"Vitamin D deficiency in patients with inflammatory bowel disease: Association with disease activity and quality of life","volume":"35","author":"Ulitsky","year":"2011","journal-title":"J. Parenter. Enteral. Nutr."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"1228","DOI":"10.1016\/j.dld.2020.06.003","article-title":"Onset of ulcerative colitis during SARS-CoV-2 infection","volume":"52","author":"Calabrese","year":"2020","journal-title":"Dig. Liver Dis."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1038\/s41575-020-00389-y","article-title":"COVID-19 and acute pancreatitis: Examining the causality","volume":"18","author":"Capurso","year":"2021","journal-title":"Nat. Rev. Gastroenterol. Hepatol."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/12\/17\/5520\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:38:51Z","timestamp":1760128731000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/12\/17\/5520"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,8,25]]},"references-count":58,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2023,9]]}},"alternative-id":["jcm12175520"],"URL":"https:\/\/doi.org\/10.3390\/jcm12175520","relation":{},"ISSN":["2077-0383"],"issn-type":[{"type":"electronic","value":"2077-0383"}],"subject":[],"published":{"date-parts":[[2023,8,25]]}}}