The relationship between serum 25-hydroxyvitamin D levels and the severity of COVID-19 disease and its mortality
Maryam Vasheghani, Nasrin Jannati, Parvaneh Baghaei, Mitra Rezaei, Roqayeh Aliyari, Majid Marjani
Scientific Reports, doi:10.1038/s41598-021-97017-9
Supplemental vitamin D can reduce the risk and mortality of viral pneumonia. The relationship between 25 hydroxyvitamin D [25(OH)D] levels and the severity and mortality of Coronavirus disease 2019 (COVID-19) was evaluated. In this cross-sectional study, the admitted patients with COVID-19 were categorized as mild, moderate, severe, and critical based on clinical and radiologic characteristics. Calcium, phosphorus, albumin, creatinine, and serum 25(OH)D were measured and their correlation with the severity of disease and mortality were analyzed. During 2 months, 508 patients (442 patients in general wards and 66 patients in the intensive care unit (ICU)) were included. The participants were 56 ± 17 years old (52% male, 37% with comorbidity). Concerning severity, 13%, 42%, 36%, and 9% had mild, moderate, severe, and critical diseases, respectively. The mortality rate was 10.8%. Admission to ICU, severity of disease and mortality decreased significantly across quartiles of 25(OH)D. According to multivariate logistic regression analysis, disease mortality had a positive correlation with age and had a negative correlation with the serum level of 25(OH)D, calcium, and albumin. In hospitalized patients with COVID-19, low 25(OH)D was associated with severe disease and increased ICU admission and mortality rate. In late 2019, a new coronavirus was identified as a cause of a cluster of pneumonia cases in China which is named COVID-19 disease 1 . Currently, COVID-19 is pandemic 2 . In Iran, 612,772 people as the definitive cases of COVID-19 have been reported by November 10, 2020, and 34,864 people have died 3 . Manifestations of the COVID-19 range from asymptomatic carriers to acute respiratory failure and death 4 . Complications include acute respiratory failure, cytokine release syndrome, increased coagulation factors, and multi-organ damage which are associated with poor prognosis 5, 6 . The overall mortality rate until November 18, 2020, is about 2.4% (1,333,742 deaths between 55,326,907 patients) 7 . Old age, cardiovascular disease, diabetes, high blood pressure, chronic lung disease, cancer, chronic kidney disease, people with defective or suppressed immune systems, obesity, and chronic liver disease have been identified as risk factors for severe disease or mortality 4, 6, 8, 9 . There is currently no specific treatment against COVID-19 disease 10 . Currently, the most important way to deal with this disease is prevention and control of the conditions that are considered as a risk factor for the more severe course, and complications. There is evidence from influenza A and severe acute respiratory syndrome (SARS) epidemics suggesting a role for vitamin D in these diseases 11 . Previous studies have suggested an association between vitamin D deficiency and an increased chance of developing bacterial and/or viral pneumonia due to viruses such as SARS, MERS, and Influenza A. COVID-19 disease is more prevalent and severe in winter and is more common..
Author contributions M.V. designed and worked in all steps of project. She wrote the manuscript and reviewed it. She revised and edited the article in all steps; N.J. collected data; P.B. Analyzed data; MR: had done laboratory tests. She reviewed and edited manuscript. R.A.: Analyzed data, corrected manuscript after revision. M.M.: supervised investigation and edited the manuscript.
Funding The authors do not receive any funding for this study.
Competing interests The authors declare no competing interests.
References
Abate, Ahmed Ali, Mantfardo, Basu, Rate of intensive care unit admission and outcomes among patients with coronavirus: A systematic review and Meta-analysis, PLoS ONE,
doi:10.1371/journal.pone.0235653Annweiler, Vitamin D supplementation associated to better survival in hospitalized frail elderly COVID-19 patients: The GERIA-COVID quasi-experimental study, Nutrients,
doi:10.3390/nu12113377Araki, Vitamin D intoxication with severe hypercalcemia due to manufacturing and labeling errors of two dietary supplements made in the United States, J. Clin. Endocrinol. Metab,
doi:10.1210/jc.2011-1443Bajgain, Badal, Bajgain, Santana, Prevalence of comorbidities among individuals with COVID-19: A rapid review of current literature, Am. J. Infect. Control,
doi:10.1016/j.ajic.2020.06.213Bakhshayeshkaram, Haseli, Iranpour, Radiological mimickers of COVID-19 pneumonia: A pictorial review, Tanaffos
Carpagnano, Vitamin D deficiency as a predictor of poor prognosis in patients with acute respiratory failure due to COVID-19, J. Endocrinol. Investig,
doi:10.1007/s40618-020-01370-xCastillo, Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: A pilot randomized clinical study, J. Steroid Biochem. Mol. Biol,
doi:10.1016/j.jsbmb.2020.105751Cereda, Vitamin D supplementation and outcomes in coronavirus disease 2019 (COVID-19) patients from the outbreak area of Lombardy, Nutrition,
doi:10.1016/j.nut.2020.111055Chen, Clinical characteristics of 113 deceased patients with coronavirus disease 2019: Retrospective study, BMJ,
doi:10.1136/bmj.m1091D' Avolio, 25-Hydroxyvitamin D concentrations are lower in patients with positive PCR for SARS-CoV-2, Nutrients,
doi:10.3390/nu12051359Ejtahed, Shab-Bidar, Hosseinpanah, Mirmiran, Azizi, Estimation of vitamin D intake based on a scenario for fortification of dairy products with vitamin D in a tehranian population, Iran. J. Am. Coll. Nutr,
doi:10.1080/07315724.2015.1022269Ferrari, Locatelli, No significant association between vitamin D and COVID-19. A retrospective study from a northern Italian hospital, Int. J. Vitam. Nutr. Res,
doi:10.1024/0300-9831/a000687French, Mcdonnell, Vieth, 25-Hydroxyvitamin D variability within-person due to diurnal rhythm and illness: A case report, J. Med. Case Rep,
doi:10.1186/s13256-018-1948-9Garcia, Prognostic factors associated with mortality risk and disease progression in 639 critically ill patients with COVID-19 in Europe: Initial report of the international RISC-19-ICU prospective observational cohort,
doi:10.1016/j.eclinm.2020.100449Gebhard, Regitz-Zagrosek, Neuhauser, Morgan, Klein, Impact of sex and gender on COVID-19 outcomes in Europe, Biol. Sex Differ,
doi:10.1186/s13293-020-00304-9Giustina, Consensus statement from 2nd international conference on controversies in vitamin D, Rev. Endocr. Metab. Disord,
doi:10.1007/s11154-019-09532-wGrant, Evidence that vitamin D supplementation could reduce risk of influenza and COVID-19 infections and deaths, Nutrients,
doi:10.3390/nu12040988Greiller, Martineau, Modulation of the immune response to respiratory viruses by vitamin D, Nutrients,
doi:10.3390/nu7064240Griffin, Vitamin D and COVID-19: Evidence and recommendations for supplementation, R. Soc. Open Sci,
doi:10.1098/rsos.201912Holick, The vitamin D deficiency pandemic: Approaches for diagnosis, treatment and prevention, Rev. Endocr. Metab. Disord,
doi:10.1007/s11154-017-9424-1Huang, Hypoalbuminemia predicts the outcome of COVID-19 independent of age and co-morbidity, J. Med. Virol,
doi:10.1002/jmv.26003Jain, Analysis of vitamin D level among asymptomatic and critically ill COVID-19 patients and its correlation with inflammatory markers, Sci. Rep,
doi:10.1038/s41598-020-77093-zJevalikar, Lack of association of baseline 25-hydroxyvitamin D levels with disease severity and mortality in Indian patients hospitalized for COVID-19, Sci Rep,
doi:10.1038/s41598-021-85809-yKabootari, Akbarpour, Azizi, Hadaegh, Sex specific impact of different obesity phenotypes on the risk of incident hypertension: Tehran lipid and glucose study, Nutr. Metab. (Lond.),
doi:10.1186/s12986-019-0340-0Ling, High-dose cholecalciferol booster therapy is associated with a reduced risk of mortality in patients with COVID-19: A cross-sectional multi-centre observational study, Nutrients,
doi:10.3390/nu12123799Mahmoudi, Rezaei, Mansouri, Marjani, Mansouri, Immunologic features in coronavirus disease 2019: Functional exhaustion of T cells and cytokine storm, J. Clin. Immunol,
doi:10.1007/s10875-020-00824-4Malacova, Prevalence and predictors of vitamin D deficiency in a nationally representative sample of adults participating in the 2011-2013 Australian Health Survey, Br. J. Nutr,
doi:10.1017/S0007114519000151Mamani, Muceli, Ghasemi Basir, Vasheghani, Poorolajal, Association between serum concentration of 25-hydroxyvitamin D and community-acquired pneumonia: A case-control study, Int. J. Gen. Med,
doi:10.2147/IJGM.S149049Mccartney, Byrne, Optimization of vitamin D status for enhanced immuno-protection against COVID-19, Iran. Med. J
Miroliaee, Salamzadeh, Shokouhi, Sahraei, The study of vitamin D administration effect on CRP and Interleukin-6 as prognostic biomarkers of ventilator associated pneumonia, J. Crit. Care,
doi:10.1016/j.jcrc.2017.08.040Onder, Rezza, Brusaferro, Case-fatality rate and characteristics of patients dying in relation to COVID-19 in Italy, JAMA,
doi:10.1001/jama.2020.4683Panagiotou, Low serum 25-hydroxyvitamin D (25[OH]D) levels in patients hospitalized with COVID-19 are associated with greater disease severity, Clin. Endocrinol,
doi:10.1111/cen.14276Pereira, Dantas Damascena, Galvão Azevedo, De Almeida, Da Mota, Vitamin D deficiency aggravates COVID-19: Systematic review and meta-analysis, Crit. Rev. Food Sci. Nutr,
doi:10.1080/10408398.2020.1841090Price-Haywood, Burton, Fort, Seoane, Hospitalization and mortality among black patients and white patients with COVID-19, N. Engl. J. Med,
doi:10.1056/NEJMsa2011686Richardson, Presenting characteristics, comorbidities, and outcomes among 5700 patients hospitalized with COVID-19 in the New York City area, JAMA,
doi:10.1001/jama.2020.6775Smolders, Van Den Ouweland, Geven, Pickkers, Kox, Letter to the Editor: Vitamin D deficiency in COVID-19: Mixing up cause and consequence, Metabolism,
doi:10.1016/j.metabol.2020.154434Sun, Serum calcium as a biomarker of clinical severity and prognosis in patients with coronavirus disease 2019, Aging,
doi:10.18632/aging.103526Tabrizi, High prevalence of vitamin D deficiency among iranian population: A systematic review and meta-analysis, Iran. J. Med. Sci
Wang, Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China, JAMA,
doi:10.1001/jama.2020.1585Wiersinga, Rhodes, Cheng, Peacock, Prescott, Pathophysiology, transmission, diagnosis, and treatment of coronavirus disease 2019 (COVID-19): A review, JAMA,
doi:10.1001/jama.2020.12839Wong, Saier, The SARS-coronavirus infection cycle: A survey of viral membrane proteins, their functional interactions and pathogenesis, Int. J. Mol. Sci,
doi:10.3390/ijms22031308Yang, Prevalence of comorbidities and its effects in patients infected with SARS-CoV-2: A systematic review and metaanalysis, Int. J. Infect. Dis,
doi:10.1016/j.ijid.2020.03.017Zheng, Vitamin D attenuates lung injury via stimulating epithelial repair, reducing epithelial cell apoptosis and inhibits TGF-β induced epithelial to mesenchymal transition, Biochem. Pharmacol,
doi:10.1016/j.bcp.2020.113955{ 'indexed': {'date-parts': [[2024, 3, 27]], 'date-time': '2024-03-27T18:34:07Z', 'timestamp': 1711564447598},
'reference-count': 68,
'publisher': 'Springer Science and Business Media LLC',
'issue': '1',
'license': [ { 'start': { 'date-parts': [[2021, 9, 2]],
'date-time': '2021-09-02T00:00:00Z',
'timestamp': 1630540800000},
'content-version': 'tdm',
'delay-in-days': 0,
'URL': 'https://creativecommons.org/licenses/by/4.0'},
{ 'start': { 'date-parts': [[2021, 9, 2]],
'date-time': '2021-09-02T00:00:00Z',
'timestamp': 1630540800000},
'content-version': 'vor',
'delay-in-days': 0,
'URL': 'https://creativecommons.org/licenses/by/4.0'}],
'content-domain': {'domain': ['link.springer.com'], 'crossmark-restriction': False},
'abstract': '<jats:title>Abstract</jats:title><jats:p>Supplemental vitamin D can reduce the risk and '
'mortality of viral pneumonia. The relationship between 25 hydroxyvitamin D [25(OH)D] levels '
'and the severity and mortality of Coronavirus disease 2019 (COVID-19) was evaluated. In this '
'cross-sectional study, the admitted patients with COVID-19 were categorized as mild, '
'moderate, severe, and critical based on clinical and radiologic characteristics. Calcium, '
'phosphorus, albumin, creatinine, and serum 25(OH)D were measured and their correlation with '
'the severity of disease and mortality were analyzed. During 2\xa0months, 508 patients (442 '
'patients in general wards and 66 patients in the intensive care unit (ICU)) were included. '
'The participants were 56\u2009±\u200917\xa0years old (52% male, 37% with comorbidity). '
'Concerning severity, 13%, 42%, 36%, and 9% had mild, moderate, severe, and critical diseases, '
'respectively. The mortality rate was 10.8%. Admission to ICU, severity of disease and '
'mortality decreased significantly across quartiles of 25(OH)D. According to multivariate '
'logistic regression analysis, disease mortality had a positive correlation with age and had a '
'negative correlation with the serum level of 25(OH)D, calcium, and albumin. In hospitalized '
'patients with COVID-19, low 25(OH)D was associated with severe disease and increased ICU '
'admission and mortality rate.</jats:p>',
'DOI': '10.1038/s41598-021-97017-9',
'type': 'journal-article',
'created': {'date-parts': [[2021, 9, 23]], 'date-time': '2021-09-23T14:32:14Z', 'timestamp': 1632407534000},
'update-policy': 'http://dx.doi.org/10.1007/springer_crossmark_policy',
'source': 'Crossref',
'is-referenced-by-count': 19,
'title': 'The relationship between serum 25-hydroxyvitamin D levels and the severity of COVID-19 disease '
'and its mortality',
'prefix': '10.1038',
'volume': '11',
'author': [ {'given': 'Maryam', 'family': 'Vasheghani', 'sequence': 'first', 'affiliation': []},
{'given': 'Nasrin', 'family': 'Jannati', 'sequence': 'additional', 'affiliation': []},
{'given': 'Parvaneh', 'family': 'Baghaei', 'sequence': 'additional', 'affiliation': []},
{'given': 'Mitra', 'family': 'Rezaei', 'sequence': 'additional', 'affiliation': []},
{'given': 'Roqayeh', 'family': 'Aliyari', 'sequence': 'additional', 'affiliation': []},
{'given': 'Majid', 'family': 'Marjani', 'sequence': 'additional', 'affiliation': []}],
'member': '297',
'published-online': {'date-parts': [[2021, 9, 2]]},
'reference': [ { 'key': '97017_CR1',
'volume-title': 'WHO Director-General’s Opening Remarks at the World Health Assembly—9 '
'November 2020',
'author': 'World Health Organization',
'year': '2020',
'unstructured': 'World Health Organization. WHO Director-General’s Opening Remarks at the '
'World Health Assembly—9 November 2020 (WHO, 2020).'},
{ 'key': '97017_CR2',
'volume-title': 'Rolling Updates on Coronavirus Disease (COVID-19)',
'author': 'World Health Organization',
'year': '2020',
'unstructured': 'World Health Organization. Rolling Updates on Coronavirus Disease '
'(COVID-19) (WHO, 2020).'},
{ 'key': '97017_CR3',
'doi-asserted-by': 'publisher',
'DOI': '10.1596/34819',
'volume-title': 'Weekly Epidemiological Update—3 November 2020',
'author': 'World Health Organization',
'year': '2020',
'unstructured': 'World Health Organization. Weekly Epidemiological Update—3 November 2020 '
'(WHO, 2020).'},
{ 'key': '97017_CR4',
'doi-asserted-by': 'publisher',
'DOI': '10.1001/jama.2020.2648',
'author': 'Z Wu',
'year': '2020',
'unstructured': 'Wu, Z. & McGoogan, J. M. Characteristics of and important lessons from '
'the coronavirus disease 2019 (COVID-19) outbreak in China summary of a '
'report of 72,314 cases from the Chinese center for disease control and '
'prevention. JAMA. https://doi.org/10.1001/jama.2020.2648 (2020).',
'journal-title': 'JAMA'},
{ 'issue': '11',
'key': '97017_CR5',
'doi-asserted-by': 'publisher',
'first-page': '1061',
'DOI': '10.1001/jama.2020.1585',
'volume': '323',
'author': 'D Wang',
'year': '2020',
'unstructured': 'Wang, D. et al. Clinical characteristics of 138 hospitalized patients '
'with 2019 novel coronavirus–infected pneumonia in Wuhan, China. JAMA. '
'323(11), 1061–1069. https://doi.org/10.1001/jama.2020.1585 (2020).',
'journal-title': 'China. JAMA.'},
{ 'key': '97017_CR6',
'doi-asserted-by': 'publisher',
'first-page': 'm1091',
'DOI': '10.1136/bmj.m1091',
'volume': '368',
'author': 'T Chen',
'year': '2020',
'unstructured': 'Chen, T. et al. Clinical characteristics of 113 deceased patients with '
'coronavirus disease 2019: Retrospective study. BMJ 368, m1091. '
'https://doi.org/10.1136/bmj.m1091 (2020).',
'journal-title': 'BMJ'},
{ 'key': '97017_CR7',
'volume-title': 'Coronavirus Disease (COVID-19) Pandemic, Coronavirus Disease (COVID-19) '
'Outbreak Situation',
'author': 'World Health Organization',
'year': '2020',
'unstructured': 'World Health Organization. Coronavirus Disease (COVID-19) Pandemic, '
'Coronavirus Disease (COVID-19) Outbreak Situation (WHO, 2020).'},
{ 'key': '97017_CR8',
'doi-asserted-by': 'publisher',
'DOI': '10.1001/jama.2020.4683',
'author': 'G Onder',
'year': '2020',
'unstructured': 'Onder, G., Rezza, G. & Brusaferro, S. Case-fatality rate and '
'characteristics of patients dying in relation to COVID-19 in Italy. '
'JAMA. https://doi.org/10.1001/jama.2020.4683 (2020).',
'journal-title': 'JAMA'},
{ 'key': '97017_CR9',
'doi-asserted-by': 'publisher',
'DOI': '10.1016/j.ijid.2020.03.031',
'author': 'E Shim',
'year': '2020',
'unstructured': 'Shim, E., Tariq, A., Choi, W., Lee, Y. & Chowell, G. Transmission '
'potential and severity of COVID-19 in South Korea. Int. J. Infect. Dis. '
'https://doi.org/10.1016/j.ijid.2020.03.031 (2020).',
'journal-title': 'Int. J. Infect. Dis.'},
{ 'key': '97017_CR10',
'doi-asserted-by': 'publisher',
'first-page': '40',
'DOI': '10.1186/s13578-020-00404-4',
'volume': '10',
'author': 'KS Yuen',
'year': '2020',
'unstructured': 'Yuen, K. S., Ye, Z. W., Fung, S. Y., Chan, C. P. & Jin, D. Y. SARS-CoV-2 '
'and COVID-19: The most important research questions. Cell Biosci. 10, '
'40. https://doi.org/10.1186/s13578-020-00404-4 (2020).',
'journal-title': 'Cell Biosci.'},
{ 'issue': '12',
'key': '97017_CR11',
'doi-asserted-by': 'publisher',
'first-page': '201912',
'DOI': '10.1098/rsos.201912',
'volume': '7',
'author': 'G Griffin',
'year': '2020',
'unstructured': 'Griffin, G. et al. Vitamin D and COVID-19: Evidence and recommendations '
'for supplementation. R. Soc. Open Sci. 7(12), 201912. '
'https://doi.org/10.1098/rsos.201912 (2020).',
'journal-title': 'R. Soc. Open Sci.'},
{ 'issue': '4',
'key': '97017_CR12',
'doi-asserted-by': 'publisher',
'first-page': 'E988',
'DOI': '10.3390/nu12040988',
'volume': '12',
'author': 'WB Grant',
'year': '2020',
'unstructured': 'Grant, W. B. et al. Evidence that vitamin D supplementation could reduce '
'risk of influenza and COVID-19 infections and deaths. Nutrients 12(4), '
'E988. https://doi.org/10.3390/nu12040988 (2020).',
'journal-title': 'Nutrients'},
{ 'issue': '4',
'key': '97017_CR13',
'first-page': '58',
'volume': '113',
'author': 'DM McCartney',
'year': '2020',
'unstructured': 'McCartney, D. M. & Byrne, D. G. Optimization of vitamin D status for '
'enhanced immuno-protection against COVID-19. Iran. Med. J. 113(4), 58 '
'(2020).',
'journal-title': 'Iran. Med. J.'},
{ 'issue': '2',
'key': '97017_CR14',
'first-page': '125',
'volume': '43',
'author': 'R Tabrizi',
'year': '2018',
'unstructured': 'Tabrizi, R. et al. High prevalence of vitamin D deficiency among iranian '
'population: A systematic review and meta-analysis. Iran. J. Med. Sci. '
'43(2), 125–139 (2018).',
'journal-title': 'Iran. J. Med. Sci.'},
{ 'key': '97017_CR15',
'unstructured': 'https://www.siemens-healthineers.com/en-us/laboratory-diagnostics/assays-by-diseases-conditions/bone-metabolism-assays-global/vitamin-d-total-assay. '
'Accessed 5 Jan 2021.'},
{ 'issue': '2',
'key': '97017_CR16',
'first-page': '100',
'volume': '19',
'author': 'M Bakhshayeshkaram',
'year': '2020',
'unstructured': 'Bakhshayeshkaram, M., Haseli, S. & Iranpour, P. Radiological mimickers '
'of COVID-19 pneumonia: A pictorial review. Tanaffos 19(2), 100–107 '
'(2020).',
'journal-title': 'Tanaffos'},
{ 'key': '97017_CR17',
'doi-asserted-by': 'publisher',
'first-page': '423',
'DOI': '10.2147/IJGM.S149049',
'volume': '10',
'author': 'M Mamani',
'year': '2017',
'unstructured': 'Mamani, M., Muceli, N., Ghasemi Basir, H. R., Vasheghani, M. & '
'Poorolajal, J. Association between serum concentration of '
'25-hydroxyvitamin D and community-acquired pneumonia: A case-control '
'study. Int. J. Gen. Med. 10, 423–429. '
'https://doi.org/10.2147/IJGM.S149049 (2017).',
'journal-title': 'Int. J. Gen. Med.'},
{ 'issue': '2',
'key': '97017_CR18',
'doi-asserted-by': 'publisher',
'first-page': '153',
'DOI': '10.1007/s11154-017-9424-1',
'volume': '18',
'author': 'MF Holick',
'year': '2017',
'unstructured': 'Holick, M. F. The vitamin D deficiency pandemic: Approaches for '
'diagnosis, treatment and prevention. Rev. Endocr. Metab. Disord. 18(2), '
'153–165. https://doi.org/10.1007/s11154-017-9424-1 (2017).',
'journal-title': 'Rev. Endocr. Metab. Disord.'},
{ 'issue': '1',
'key': '97017_CR19',
'doi-asserted-by': 'publisher',
'first-page': '89',
'DOI': '10.1007/s11154-019-09532-w',
'volume': '21',
'author': 'A Giustina',
'year': '2020',
'unstructured': 'Giustina, A. et al. Consensus statement from 2nd international '
'conference on controversies in vitamin D. Rev. Endocr. Metab. Disord. '
'21(1), 89–116. https://doi.org/10.1007/s11154-019-09532-w (2020).',
'journal-title': 'Rev. Endocr. Metab. Disord.'},
{ 'issue': '12',
'key': '97017_CR20',
'doi-asserted-by': 'publisher',
'first-page': '3603',
'DOI': '10.1210/jc.2011-1443',
'volume': '96',
'author': 'T Araki',
'year': '2011',
'unstructured': 'Araki, T. et al. Vitamin D intoxication with severe hypercalcemia due to '
'manufacturing and labeling errors of two dietary supplements made in the '
'United States. J. Clin. Endocrinol. Metab. 96(12), 3603–3608. '
'https://doi.org/10.1210/jc.2011-1443 (2011).',
'journal-title': 'J. Clin. Endocrinol. Metab.'},
{ 'key': '97017_CR21',
'unstructured': 'World Health Organization. Clinical Management of COVID-19. Interim '
'Guidance. COVID-19: Clinical care. WHO/Publications/Overview/Clinical '
'management of COVID-19. WHO Reference Number: '
'WHO/2019-nCoV/clinical/2020.5 (2020). '
'https://www.who.int/publications/i/item/clinical-management-of-COVID-19. '
'Accessed 5 Jan 2021.'},
{ 'key': '97017_CR22',
'doi-asserted-by': 'publisher',
'first-page': '16',
'DOI': '10.1186/s12986-019-0340-0',
'volume': '16',
'author': 'M Kabootari',
'year': '2019',
'unstructured': 'Kabootari, M., Akbarpour, S., Azizi, F. & Hadaegh, F. Sex specific '
'impact of different obesity phenotypes on the risk of incident '
'hypertension: Tehran lipid and glucose study. Nutr. Metab. (Lond.). 16, '
'16. https://doi.org/10.1186/s12986-019-0340-0 (2019).',
'journal-title': 'Nutr. Metab. (Lond.).'},
{ 'issue': '26',
'key': '97017_CR23',
'doi-asserted-by': 'publisher',
'first-page': '2534',
'DOI': '10.1056/NEJMsa2011686',
'volume': '382',
'author': 'EG Price-Haywood',
'year': '2020',
'unstructured': 'Price-Haywood, E. G., Burton, J., Fort, D. & Seoane, L. Hospitalization '
'and mortality among black patients and white patients with COVID-19. N. '
'Engl. J. Med. 382(26), 2534–2543. https://doi.org/10.1056/NEJMsa2011686 '
'(2020).',
'journal-title': 'N. Engl. J. Med.'},
{ 'issue': '2',
'key': '97017_CR24',
'doi-asserted-by': 'publisher',
'first-page': 'e16',
'DOI': '10.1016/j.jinf.2020.04.021',
'volume': '81',
'author': 'Z Zheng',
'year': '2020',
'unstructured': 'Zheng, Z. et al. Risk factors of critical & mortal COVID-19 cases: A '
'systematic literature review and meta-analysis. J. Infect. 81(2), '
'e16–e25. https://doi.org/10.1016/j.jinf.2020.04.021 (2020).',
'journal-title': 'J. Infect.'},
{ 'issue': '11',
'key': '97017_CR25',
'doi-asserted-by': 'publisher',
'first-page': '10004',
'DOI': '10.18632/aging.103493',
'volume': '12',
'author': 'MV Blagosklonny',
'year': '2020',
'unstructured': 'Blagosklonny, M. V. From causes of aging to death from COVID-19. Aging '
'(Albany NY). 12(11), 10004–10021. https://doi.org/10.18632/aging.103493 '
'(2020).',
'journal-title': 'Aging (Albany NY).'},
{ 'issue': '1',
'key': '97017_CR26',
'doi-asserted-by': 'publisher',
'first-page': '29',
'DOI': '10.1186/s13293-020-00304-9',
'volume': '11',
'author': 'C Gebhard',
'year': '2020',
'unstructured': 'Gebhard, C., Regitz-Zagrosek, V., Neuhauser, H. K., Morgan, R. & Klein, '
'S. L. Impact of sex and gender on COVID-19 outcomes in Europe. Biol. Sex '
'Differ. 11(1), 29. https://doi.org/10.1186/s13293-020-00304-9 (2020).',
'journal-title': 'Biol. Sex Differ.'},
{ 'issue': '2',
'key': '97017_CR27',
'doi-asserted-by': 'publisher',
'first-page': '238',
'DOI': '10.1016/j.ajic.2020.06.213',
'volume': '49',
'author': 'KT Bajgain',
'year': '2021',
'unstructured': 'Bajgain, K. T., Badal, S., Bajgain, B. B. & Santana, M. J. Prevalence of '
'comorbidities among individuals with COVID-19: A rapid review of current '
'literature. Am. J. Infect. Control. 49(2), 238–246. '
'https://doi.org/10.1016/j.ajic.2020.06.213 (2021).',
'journal-title': 'Am. J. Infect. Control.'},
{ 'key': '97017_CR28',
'doi-asserted-by': 'publisher',
'first-page': '91',
'DOI': '10.1016/j.ijid.2020.03.017',
'volume': '94',
'author': 'J Yang',
'year': '2020',
'unstructured': 'Yang, J. et al. Prevalence of comorbidities and its effects in patients '
'infected with SARS-CoV-2: A systematic review and meta-analysis. Int. J. '
'Infect. Dis. 94, 91–95. https://doi.org/10.1016/j.ijid.2020.03.017 '
'(2020).',
'journal-title': 'Int. J. Infect. Dis.'},
{ 'key': '97017_CR29',
'doi-asserted-by': 'publisher',
'DOI': '10.1016/j.eclinm.2020.100449',
'author': 'PD Wendel Garcia',
'year': '2020',
'unstructured': 'Wendel Garcia, P. D. et al. Prognostic factors associated with mortality '
'risk and disease progression in 639 critically ill patients with '
'COVID-19 in Europe: Initial report of the international RISC-19-ICU '
'prospective observational cohort. EClinicalMedicine. '
'https://doi.org/10.1016/j.eclinm.2020.100449 (2020).',
'journal-title': 'EClinicalMedicine.'},
{ 'key': '97017_CR30',
'doi-asserted-by': 'publisher',
'unstructured': 'Richardson, S., et al. Presenting characteristics, comorbidities, and '
'outcomes among 5700 patients hospitalized with COVID-19 in the New York '
'City area. JAMA 323(20), 2052–2059 (2020). '
'https://doi.org/10.1001/jama.2020.6775. Erratum in: JAMA 323(20), 2098 '
'(2020).',
'DOI': '10.1001/jama.2020.6775'},
{ 'key': '97017_CR31',
'unstructured': 'https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports. '
'Accessed 5 Jan 2021.'},
{ 'key': '97017_CR32',
'unstructured': 'The Ministry of Health of Iran. Identification of 13843 New Patients '
'with Covid 19 in the Country/5832 Patients are Admitted to the Intensive '
'Care Unit, Number 217880. https://behdasht.gov.ir/news/NEWS. Accessed 5 '
'Jan 2021.'},
{ 'issue': '8',
'key': '97017_CR33',
'doi-asserted-by': 'publisher',
'first-page': '782',
'DOI': '10.1001/jama.2020.12839',
'volume': '324',
'author': 'WJ Wiersinga',
'year': '2020',
'unstructured': 'Wiersinga, W. J., Rhodes, A., Cheng, A. C., Peacock, S. J. & Prescott, '
'H. C. Pathophysiology, transmission, diagnosis, and treatment of '
'coronavirus disease 2019 (COVID-19): A review. JAMA 324(8), 782–793. '
'https://doi.org/10.1001/jama.2020.12839 (2020).',
'journal-title': 'JAMA'},
{ 'issue': '7',
'key': '97017_CR34',
'doi-asserted-by': 'publisher',
'first-page': 'e0235653',
'DOI': '10.1371/journal.pone.0235653',
'volume': '15',
'author': 'SM Abate',
'year': '2020',
'unstructured': 'Abate, S. M., Ahmed Ali, S., Mantfardo, B. & Basu, B. Rate of intensive '
'care unit admission and outcomes among patients with coronavirus: A '
'systematic review and Meta-analysis. PLoS ONE 15(7), e0235653. '
'https://doi.org/10.1371/journal.pone.0235653 (2020).',
'journal-title': 'PLoS ONE'},
{ 'issue': '4',
'key': '97017_CR35',
'doi-asserted-by': 'publisher',
'first-page': '845',
'DOI': '10.1016/j.ecl.2017.07.002',
'volume': '46',
'author': 'N van Schoor',
'year': '2017',
'unstructured': 'van Schoor, N. & Lips, P. Global overview of vitamin D status. '
'Endocrinol. Metab. Clin. N. Am. 46(4), 845–870. '
'https://doi.org/10.1016/j.ecl.2017.07.002 (2017).',
'journal-title': 'Endocrinol. Metab. Clin. N. Am.'},
{ 'issue': '4',
'key': '97017_CR36',
'doi-asserted-by': 'publisher',
'first-page': '269',
'DOI': '10.1177/0260106018802968',
'volume': '24',
'author': 'S Vatandost',
'year': '2018',
'unstructured': 'Vatandost, S. et al. Prevalence of vitamin D deficiency in Iran: A '
'systematic review and meta-analysis. Nutr. Health 24(4), 269–278. '
'https://doi.org/10.1177/0260106018802968 (2018).',
'journal-title': 'Nutr. Health'},
{ 'issue': '5',
'key': '97017_CR37',
'doi-asserted-by': 'publisher',
'first-page': '383',
'DOI': '10.1080/07315724.2015.1022269',
'volume': '35',
'author': 'HS Ejtahed',
'year': '2016',
'unstructured': 'Ejtahed, H. S., Shab-Bidar, S., Hosseinpanah, F., Mirmiran, P. & Azizi, '
'F. Estimation of vitamin D intake based on a scenario for fortification '
'of dairy products with vitamin D in a tehranian population. Iran. J. Am. '
'Coll. Nutr. 35(5), 383–391. '
'https://doi.org/10.1080/07315724.2015.1022269 (2016).',
'journal-title': 'Iran. J. Am. Coll. Nutr.'},
{ 'issue': '12',
'key': '97017_CR38',
'doi-asserted-by': 'publisher',
'first-page': '11287',
'DOI': '10.18632/aging.103526',
'volume': '12',
'author': 'JK Sun',
'year': '2020',
'unstructured': 'Sun, J. K. et al. Serum calcium as a biomarker of clinical severity and '
'prognosis in patients with coronavirus disease 2019. Aging (Albany NY). '
'12(12), 11287–11295. https://doi.org/10.18632/aging.103526 (2020).',
'journal-title': 'Aging (Albany NY).'},
{ 'key': '97017_CR39',
'doi-asserted-by': 'publisher',
'DOI': '10.1002/jmv.26003',
'author': 'J Huang',
'year': '2020',
'unstructured': 'Huang, J. et al. Hypoalbuminemia predicts the outcome of COVID-19 '
'independent of age and co-morbidity. J. Med. Virol. '
'https://doi.org/10.1002/jmv.26003 (2020).',
'journal-title': 'J. Med. Virol.'},
{ 'issue': '1',
'key': '97017_CR40',
'doi-asserted-by': 'publisher',
'first-page': '20191',
'DOI': '10.1038/s41598-020-77093-z',
'volume': '10',
'author': 'A Jain',
'year': '2020',
'unstructured': 'Jain, A. et al. Analysis of vitamin D level among asymptomatic and '
'critically ill COVID-19 patients and its correlation with inflammatory '
'markers. Sci. Rep. 10(1), 20191. '
'https://doi.org/10.1038/s41598-020-77093-z (2020).',
'journal-title': 'Sci. Rep.'},
{ 'key': '97017_CR41',
'doi-asserted-by': 'publisher',
'DOI': '10.1136/postgradmedj-2020-138712',
'author': 'V Baktash',
'year': '2020',
'unstructured': 'Baktash, V. et al. Vitamin D status and outcomes for hospitalised older '
'patients with COVID-19. Postgrad. Med. J. '
'https://doi.org/10.1136/postgradmedj-2020-138712 (2020).',
'journal-title': 'Postgrad. Med. J.'},
{ 'issue': '1',
'key': '97017_CR42',
'doi-asserted-by': 'publisher',
'first-page': '6258',
'DOI': '10.1038/s41598-021-85809-y',
'volume': '11',
'author': 'G Jevalikar',
'year': '2021',
'unstructured': 'Jevalikar, G. et al. Lack of association of baseline 25-hydroxyvitamin D '
'levels with disease severity and mortality in Indian patients '
'hospitalized for COVID-19. Sci Rep. 11(1), 6258. '
'https://doi.org/10.1038/s41598-021-85809-y (2021).',
'journal-title': 'Sci Rep.'},
{ 'key': '97017_CR43',
'doi-asserted-by': 'publisher',
'DOI': '10.1111/cen.14276',
'author': 'G Panagiotou',
'year': '2020',
'unstructured': 'Panagiotou, G. et al. Low serum 25-hydroxyvitamin D (25[OH]D) levels in '
'patients hospitalized with COVID-19 are associated with greater disease '
'severity. Clin. Endocrinol. (Oxf.). https://doi.org/10.1111/cen.14276 '
'(2020).',
'journal-title': 'Clin. Endocrinol. (Oxf.).'},
{ 'key': '97017_CR44',
'doi-asserted-by': 'publisher',
'first-page': '105751',
'DOI': '10.1016/j.jsbmb.2020.105751',
'volume': '203',
'author': 'M Entrenas Castillo',
'year': '2020',
'unstructured': 'Entrenas Castillo, M. et al. Effect of calcifediol treatment and best '
'available therapy versus best available therapy on intensive care unit '
'admission and mortality among patients hospitalized for COVID-19: A '
'pilot randomized clinical study. J. Steroid Biochem. Mol. Biol. 203, '
'105751. https://doi.org/10.1016/j.jsbmb.2020.105751 (2020).',
'journal-title': 'J. Steroid Biochem. Mol. Biol.'},
{ 'issue': '12',
'key': '97017_CR45',
'doi-asserted-by': 'publisher',
'first-page': '3799',
'DOI': '10.3390/nu12123799',
'volume': '12',
'author': 'SF Ling',
'year': '2020',
'unstructured': 'Ling, S. F. et al. High-dose cholecalciferol booster therapy is '
'associated with a reduced risk of mortality in patients with COVID-19: A '
'cross-sectional multi-centre observational study. Nutrients 12(12), '
'3799. https://doi.org/10.3390/nu12123799 (2020).',
'journal-title': 'Nutrients'},
{ 'issue': '11',
'key': '97017_CR46',
'doi-asserted-by': 'publisher',
'first-page': '3377',
'DOI': '10.3390/nu12113377',
'volume': '12',
'author': 'G Annweiler',
'year': '2020',
'unstructured': 'Annweiler, G. et al. Vitamin D supplementation associated to better '
'survival in hospitalized frail elderly COVID-19 patients: The '
'GERIA-COVID quasi-experimental study. Nutrients 12(11), 3377. '
'https://doi.org/10.3390/nu12113377 (2020).',
'journal-title': 'Nutrients'},
{ 'issue': '5',
'key': '97017_CR47',
'doi-asserted-by': 'publisher',
'first-page': '1359',
'DOI': '10.3390/nu12051359',
'volume': '12',
'author': "A D'Avolio",
'year': '2020',
'unstructured': 'D’Avolio, A. et al. 25-Hydroxyvitamin D concentrations are lower in '
'patients with positive PCR for SARS-CoV-2. Nutrients 12(5), 1359. '
'https://doi.org/10.3390/nu12051359 (2020).',
'journal-title': 'Nutrients'},
{ 'key': '97017_CR48',
'doi-asserted-by': 'publisher',
'first-page': '111055',
'DOI': '10.1016/j.nut.2020.111055',
'volume': '82',
'author': 'E Cereda',
'year': '2020',
'unstructured': 'Cereda, E. et al. Vitamin D supplementation and outcomes in coronavirus '
'disease 2019 (COVID-19) patients from the outbreak area of Lombardy, '
'Italy. Nutrition 82, 111055. https://doi.org/10.1016/j.nut.2020.111055 '
'(2020).',
'journal-title': 'Nutrition'},
{ 'issue': '9',
'key': '97017_CR49',
'doi-asserted-by': 'publisher',
'first-page': '2757',
'DOI': '10.3390/nu12092757',
'volume': '12',
'author': 'A Radujkovic',
'year': '2020',
'unstructured': 'Radujkovic, A. et al. Vitamin D deficiency and outcome of COVID-19 '
'patients. Nutrients 12(9), 2757. https://doi.org/10.3390/nu12092757 '
'(2020).',
'journal-title': 'Nutrients'},
{ 'issue': '9',
'key': '97017_CR50',
'doi-asserted-by': 'publisher',
'first-page': 'e2019722',
'DOI': '10.1001/jamanetworkopen.2020.19722',
'volume': '3',
'author': 'DO Meltzer',
'year': '2020',
'unstructured': 'Meltzer, D. O. et al. Association of vitamin D status and other clinical '
'characteristics with COVID-19 test results. JAMA Netw. Open 3(9), '
'e2019722. https://doi.org/10.1001/jamanetworkopen.2020.19722 (2020).',
'journal-title': 'JAMA Netw. Open'},
{ 'key': '97017_CR51',
'doi-asserted-by': 'publisher',
'DOI': '10.1080/10408398.2020.1841090',
'author': 'M Pereira',
'year': '2020',
'unstructured': 'Pereira, M., Dantas Damascena, A., Galvão Azevedo, L. M., de Almeida, O. '
'T. & da Mota, S. J. Vitamin D deficiency aggravates COVID-19: Systematic '
'review and meta-analysis. Crit. Rev. Food Sci. Nutr. '
'https://doi.org/10.1080/10408398.2020.1841090 (2020).',
'journal-title': 'Crit. Rev. Food Sci. Nutr.'},
{ 'issue': '4',
'key': '97017_CR52',
'doi-asserted-by': 'publisher',
'first-page': '765',
'DOI': '10.1007/s40618-020-01370-x',
'volume': '44',
'author': 'GE Carpagnano',
'year': '2021',
'unstructured': 'Carpagnano, G. E. et al. Vitamin D deficiency as a predictor of poor '
'prognosis in patients with acute respiratory failure due to COVID-19. J. '
'Endocrinol. Investig. 44(4), 765–771. '
'https://doi.org/10.1007/s40618-020-01370-x (2021).',
'journal-title': 'J. Endocrinol. Investig.'},
{ 'key': '97017_CR53',
'doi-asserted-by': 'publisher',
'DOI': '10.20945/2359-3997000000343',
'author': 'CMÁ Brandão',
'year': '2021',
'unstructured': 'Brandão, C. M. Á. et al. No association between vitamin D status and '
'COVID-19 infection in São Paulo Brazil. Arch. Endocrinol. Metab. '
'https://doi.org/10.20945/2359-3997000000343 (2021).',
'journal-title': 'Arch. Endocrinol. Metab.'},
{ 'key': '97017_CR54',
'doi-asserted-by': 'publisher',
'DOI': '10.1024/0300-9831/a000687',
'author': 'D Ferrari',
'year': '2020',
'unstructured': 'Ferrari, D. & Locatelli, M. No significant association between vitamin D '
'and COVID-19. A retrospective study from a northern Italian hospital. '
'Int. J. Vitam. Nutr. Res. https://doi.org/10.1024/0300-9831/a000687 '
'(2020).',
'journal-title': 'Int. J. Vitam. Nutr. Res.'},
{ 'issue': '8',
'key': '97017_CR55',
'doi-asserted-by': 'publisher',
'first-page': '820',
'DOI': '10.1177/1060028020928052',
'volume': '54',
'author': 'KK Adams',
'year': '2020',
'unstructured': 'Adams, K. K. & Baker, W. L. Sobieraj DM myth busters: Dietary '
'supplements and COVID-19. Ann. Pharmacother. 54(8), 820–826. '
'https://doi.org/10.1177/1060028020928052 (2020).',
'journal-title': 'Ann. Pharmacother.'},
{ 'issue': '7',
'key': '97017_CR56',
'doi-asserted-by': 'publisher',
'first-page': '974',
'DOI': '10.1007/s10875-020-00824-4',
'volume': '40',
'author': 'S Mahmoudi',
'year': '2020',
'unstructured': 'Mahmoudi, S., Rezaei, M., Mansouri, N., Marjani, M. & Mansouri, D. '
'Immunologic features in coronavirus disease 2019: Functional exhaustion '
'of T cells and cytokine storm. J. Clin. Immunol. 40(7), 974–976. '
'https://doi.org/10.1007/s10875-020-00824-4 (2020).',
'journal-title': 'J. Clin. Immunol.'},
{ 'key': '97017_CR57',
'doi-asserted-by': 'publisher',
'DOI': '10.1016/j.jiph.2020.06.021',
'author': 'N Ali',
'year': '2020',
'unstructured': 'Ali, N. Role of vitamin D in preventing of COVID-19 infection, '
'progression and severity. J Infect Public Health. '
'https://doi.org/10.1016/j.jiph.2020.06.021 (2020).',
'journal-title': 'J Infect Public Health.'},
{ 'issue': '3',
'key': '97017_CR58',
'doi-asserted-by': 'publisher',
'first-page': '194',
'DOI': '10.1016/j.jcv.2010.12.00',
'volume': '50',
'author': 'JA Beard',
'year': '2011',
'unstructured': 'Beard, J. A., Bearden, A. & Striker, R. Vitamin D and the anti-viral '
'state. J. Clin. Virol. 50(3), 194–200. '
'https://doi.org/10.1016/j.jcv.2010.12.00 (2011).',
'journal-title': 'J. Clin. Virol.'},
{ 'issue': '6',
'key': '97017_CR59',
'doi-asserted-by': 'publisher',
'first-page': '856',
'DOI': '10.1038/s41430-020-0661-0',
'volume': '74',
'author': 'M Ebadi',
'year': '2020',
'unstructured': 'Ebadi, M. & Montano-Loza, A. J. Perspective: Improving vitamin D status '
'in the management of COVID-19. Eur. J. Clin. Nutr. 74(6), 856–859. '
'https://doi.org/10.1038/s41430-020-0661-0 (2020).',
'journal-title': 'Eur. J. Clin. Nutr.'},
{ 'issue': '3',
'key': '97017_CR60',
'doi-asserted-by': 'publisher',
'first-page': '1308',
'DOI': '10.3390/ijms22031308',
'volume': '22',
'author': 'NA Wong',
'year': '2021',
'unstructured': 'Wong, N. A. & Saier, M. H. Jr. The SARS-coronavirus infection cycle: A '
'survey of viral membrane proteins, their functional interactions and '
'pathogenesis. Int. J. Mol. Sci. 22(3), 1308. '
'https://doi.org/10.3390/ijms22031308 (2021).',
'journal-title': 'Int. J. Mol. Sci.'},
{ 'issue': '6',
'key': '97017_CR61',
'doi-asserted-by': 'publisher',
'first-page': '4240',
'DOI': '10.3390/nu7064240',
'volume': '7',
'author': 'CL Greiller',
'year': '2015',
'unstructured': 'Greiller, C. L. & Martineau, A. R. Modulation of the immune response to '
'respiratory viruses by vitamin D. Nutrients 7(6), 4240–4270. '
'https://doi.org/10.3390/nu7064240 (2015).',
'journal-title': 'Nutrients'},
{ 'key': '97017_CR62',
'doi-asserted-by': 'publisher',
'first-page': '300',
'DOI': '10.1016/j.jcrc.2017.08.040',
'volume': '44',
'author': 'AE Miroliaee',
'year': '2018',
'unstructured': 'Miroliaee, A. E., Salamzadeh, J., Shokouhi, S. & Sahraei, Z. The study '
'of vitamin D administration effect on CRP and Interleukin-6 as '
'prognostic biomarkers of ventilator associated pneumonia. J. Crit. Care '
'44, 300–305. https://doi.org/10.1016/j.jcrc.2017.08.040 (2018).',
'journal-title': 'J. Crit. Care'},
{ 'issue': '2',
'key': '97017_CR63',
'doi-asserted-by': 'publisher',
'first-page': '575',
'DOI': '10.3390/nu12020575',
'volume': '12',
'author': 'DH Kim',
'year': '2020',
'unstructured': 'Kim, D. H., Meza, C. A., Clarke, H., Kim, J. S. & Hickner, R. C. Vitamin '
'D and endothelial function. Nutrients 12(2), 575. '
'https://doi.org/10.3390/nu12020575 (2020).',
'journal-title': 'Nutrients'},
{ 'key': '97017_CR64',
'doi-asserted-by': 'publisher',
'first-page': '113955',
'DOI': '10.1016/j.bcp.2020.113955',
'volume': '177',
'author': 'S Zheng',
'year': '2020',
'unstructured': 'Zheng, S. et al. Vitamin D attenuates lung injury via stimulating '
'epithelial repair, reducing epithelial cell apoptosis and inhibits TGF-β '
'induced epithelial to mesenchymal transition. Biochem. Pharmacol. 177, '
'113955. https://doi.org/10.1016/j.bcp.2020.113955 (2020).',
'journal-title': 'Biochem. Pharmacol.'},
{ 'key': '97017_CR65',
'doi-asserted-by': 'publisher',
'DOI': '10.1016/j.metabol.2021.154753',
'author': 'A Bassatne',
'year': '2021',
'unstructured': 'Bassatne, A. et al. The link between COVID-19 and VItamin D (VIVID): A '
'systematic review and meta-analysis. Metabolism. '
'https://doi.org/10.1016/j.metabol.2021.154753 (2021).',
'journal-title': 'Metabolism'},
{ 'key': '97017_CR66',
'doi-asserted-by': 'publisher',
'first-page': '154434',
'DOI': '10.1016/j.metabol.2020.154434',
'volume': '115',
'author': 'J Smolders',
'year': '2021',
'unstructured': 'Smolders, J., van den Ouweland, J., Geven, C., Pickkers, P. & Kox, M. '
'Letter to the Editor: Vitamin D deficiency in COVID-19: Mixing up cause '
'and consequence. Metabolism 115, 154434. '
'https://doi.org/10.1016/j.metabol.2020.154434 (2021).',
'journal-title': 'Metabolism'},
{ 'issue': '1',
'key': '97017_CR67',
'doi-asserted-by': 'publisher',
'first-page': '29',
'DOI': '10.1186/s13256-018-1948-9',
'volume': '13',
'author': 'CB French',
'year': '2019',
'unstructured': 'French, C. B., McDonnell, S. L. & Vieth, R. 25-Hydroxyvitamin D '
'variability within-person due to diurnal rhythm and illness: A case '
'report. J. Med. Case Rep. 13(1), 29. '
'https://doi.org/10.1186/s13256-018-1948-9 (2019).',
'journal-title': 'J. Med. Case Rep.'},
{ 'issue': '8',
'key': '97017_CR68',
'doi-asserted-by': 'publisher',
'first-page': '894',
'DOI': '10.1017/S0007114519000151',
'volume': '121',
'author': 'E Malacova',
'year': '2019',
'unstructured': 'Malacova, E. et al. Prevalence and predictors of vitamin D deficiency in '
'a nationally representative sample of adults participating in the '
'2011–2013 Australian Health Survey. Br. J. Nutr. 121(8), 894–904. '
'https://doi.org/10.1017/S0007114519000151 (2019).',
'journal-title': 'Br. J. Nutr.'}],
'container-title': 'Scientific Reports',
'original-title': [],
'language': 'en',
'link': [ { 'URL': 'https://www.nature.com/articles/s41598-021-97017-9.pdf',
'content-type': 'application/pdf',
'content-version': 'vor',
'intended-application': 'text-mining'},
{ 'URL': 'https://www.nature.com/articles/s41598-021-97017-9',
'content-type': 'text/html',
'content-version': 'vor',
'intended-application': 'text-mining'},
{ 'URL': 'https://www.nature.com/articles/s41598-021-97017-9.pdf',
'content-type': 'application/pdf',
'content-version': 'vor',
'intended-application': 'similarity-checking'}],
'deposited': { 'date-parts': [[2022, 12, 3]],
'date-time': '2022-12-03T15:37:12Z',
'timestamp': 1670081832000},
'score': 1,
'resource': {'primary': {'URL': 'https://www.nature.com/articles/s41598-021-97017-9'}},
'subtitle': [],
'short-title': [],
'issued': {'date-parts': [[2021, 9, 2]]},
'references-count': 68,
'journal-issue': {'issue': '1', 'published-online': {'date-parts': [[2021, 12]]}},
'alternative-id': ['97017'],
'URL': 'http://dx.doi.org/10.1038/s41598-021-97017-9',
'relation': {},
'ISSN': ['2045-2322'],
'subject': ['Multidisciplinary'],
'container-title-short': 'Sci Rep',
'published': {'date-parts': [[2021, 9, 2]]},
'assertion': [ { 'value': '5 January 2021',
'order': 1,
'name': 'received',
'label': 'Received',
'group': {'name': 'ArticleHistory', 'label': 'Article History'}},
{ 'value': '10 August 2021',
'order': 2,
'name': 'accepted',
'label': 'Accepted',
'group': {'name': 'ArticleHistory', 'label': 'Article History'}},
{ 'value': '2 September 2021',
'order': 3,
'name': 'first_online',
'label': 'First Online',
'group': {'name': 'ArticleHistory', 'label': 'Article History'}},
{ 'value': 'The authors declare no competing interests.',
'order': 1,
'name': 'Ethics',
'group': {'name': 'EthicsHeading', 'label': 'Competing interests'}}],
'article-number': '17594'}
