Vitamin D levels and mortality with SARS-COV-2 infection: a retrospective two-centre cohort study
Mansoor Zafar, Mangala Karkhanis, Muhammad Shahbaz, Alisha Khanna, Lucinda Barry, Saba Alam, Kamal Lawrence, Bipin Pun, Reem Eldebri, Opeyemi Makanjuola, Dana Safarova, Mariya Farooq, Hesam Nooredinavand, Frderic Cuison, Karuna Subba, Ratan Singh Randhawa, Johannes Hegner, Ojofeitimi Oluwamayowa, Amr Elyasaky, Bolurin Adekunle, Manivannan Periasamy, Mohamed Abdelbagi, Zahra Maryam, Bao Khuu, Andreia Esteves Morete, Giulio Ciroi, Steve Moran, William O'neill, Maaryah J Zafar, Nadiyah Zafar, Mirej Patel, Raphael Golez, Abubakr Hadid, Tila Muhammad, Philip Mayhead, Mark Whitehead, Umesh Dashora
Postgraduate Medical Journal, doi:10.1136/postgradmedj-2021-140564
Background The role of vitamin D in increased mortality with SARS-COV-2 virus, namely, COVID-19, remains uncertain. We analysed all the patients who were treated as COVID-19-positive with or without a positive swab and were tested for vitamin D levels. Methods This was a retrospective, study involving 1226 patients swabbed for SARS-CoV-2 between the 10 February 2020 and 1 May 2020 at two hospitals of East Sussex Healthcare NHS Trust. Patients who were swabpositive for COVID-19 or treated as COVID-19-positive on clinical grounds even though swab results were negative were included in this study. We analysed the association of vitamin D levels and mortality, assessing linear and non-linear associations. Results A total of 1226 patients had SARS-CoV-2 RNA swabs in this period with age range from 1 year to 101 years. A cohort of 433 of these patients had swabs and recent vitamin D levels anytime in the previous 3 months. Mortality rates were not found to be associated with vitamin D levels (OR=1.04, 95% CI 0.96 to 1.12). Conclusion Our findings suggest similar mortality risk from COVID-19 irrespective of the levels of vitamin D. Larger prospective studies will be needed to confirm these findings.
Collaborators Information is entered in the paper as coauthors in the main paper as previously advised by the journal. Contributors MZ designed the study and formed the steering group, which was responsible for ongoing evaluation for study design development, and led the methodological data collection from hospital electronic system towards comorbidities and access to blood test results. SM and WO assisted with electronic record for COVID-19 swab results for all patients from Conquest Hospital and Eastbourne District General Hospital. MZ, MK, MS, AK, LB, SA, KL, BP, RE, OM, DS, MF, HN, FC, KS, RSR, JH, OO, AE, BA, MP, MA, ZM, BK, AEM, GC, MJZ, NZ, MP, RG, AH and TM contributed with data acquisition and data entry. MZ, MK, MS, RSR, RE, SA and BP were responsible for the ongoing evaluation for study design development. SA, JH, DS, BP, ZM, BK, MK, JH and MP assisted with data assimilation, assisted by all other contributors. MJZ and NZ proofread the entire data for any errors. MZ and SA verified the data. MZ acted as guarantor. Statistical analysis was led by MZ, with intellectual review and support by Ms Jackie Cooper. MZ wrote the manuscript, which was reviewed by UD, MW and PM. All authors and UD approved the final version of the manuscript. Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared. Patient consent for publication Not required...
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"abstract": "<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>The role of vitamin D in increased mortality with SARS-COV-2 virus, namely, COVID-19, remains uncertain. We analysed all the patients who were treated as COVID-19-positive with or without a positive swab and were tested for vitamin D levels.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>This was a retrospective, study involving 1226 patients swabbed for SARS-CoV-2 between the 10 February 2020 and 1 May 2020 at two hospitals of East Sussex Healthcare NHS Trust. Patients who were swab-positive for COVID-19 or treated as COVID-19-positive on clinical grounds even though swab results were negative were included in this study. We analysed the association of vitamin D levels and mortality, assessing linear and non-linear associations.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>A total of 1226 patients had SARS-CoV-2 RNA swabs in this period with age range from 1 year to 101 years. A cohort of 433 of these patients had swabs and recent vitamin D levels anytime in the previous 3 months. Mortality rates were not found to be associated with vitamin D levels (OR=1.04, 95% CI 0.96 to 1.12).</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Our findings suggest similar mortality risk from COVID-19 irrespective of the levels of vitamin D. Larger prospective studies will be needed to confirm these findings.</jats:p></jats:sec>",
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