Abstract: Journal of the American College of Nutrition ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/uacn20 Association between Vitamin D Status and Risk of Developing Severe COVID-19 Infection: A MetaAnalysis of Observational Studies Mohamed Ben-Eltriki, Robert Hopefl, James M. Wright & Subrata Deb To cite this article: Mohamed Ben-Eltriki, Robert Hopefl, James M. Wright & Subrata Deb (2021): Association between Vitamin D Status and Risk of Developing Severe COVID-19 Infection: A Meta-Analysis of Observational Studies, Journal of the American College of Nutrition, DOI: 10.1080/07315724.2021.1951891 To link to this article: https://doi.org/10.1080/07315724.2021.1951891 View supplementary material Published online: 31 Aug 2021. Submit your article to this journal Article views: 1749 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=uacn20 Journal of the American College of Nutrition https://doi.org/10.1080/07315724.2021.1951891 Association between Vitamin D Status and Risk of Developing Severe COVID-19 Infection: A Meta-Analysis of Observational Studies Mohamed Ben-Eltrikia,b, Robert Hopeflc, James M. Wrighta,b,d, and Subrata Debc Cochrane Hypertension Review Group, University of British Columbia, Vancouver, Canada; bTherapeutics Initiative, Department of Anesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, Canada; cDepartment of Pharmaceutical Sciences, College of Pharmacy, Larkin University, Miami, Florida, USA; dDepartment of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, Canada a ABSTRACT ARTICLE HISTORY Objective: The relationship between 25-hydroxyvitamin D3 (25(OH)D), the surrogate marker for vitamin D3, serum concentration and COVID-19 has come to the forefront as a potential pathway to improve COVID-19 outcomes. The current evidence remains unclear on the impact of vitamin D status on the severity and outcomes of COVID-19 infection. To explore possible association between low 25(OH)D levels and risk of developing severe COVID-19 (i.e. need for invasive mechanical ventilation, the length of hospital stay, total deaths). We also aimed to understand the relationship between vitamin D insufficiency and elevated inflammatory and cardiac biomarkers. Methods: We conducted a comprehensive electronic literature search for any original research study published up to March 30, 2021. For the purpose of this review, low vitamin D status was defined as a range of serum total 25(OH)D levels of <10 to <30 ng/ml. Two independent investigators assessed study eligibility, synthesized evidence, analyzed, critically examined, and interpreted herein. Results: Twenty-four observational studies containing 3637 participants were included in the meta-analysis. The mean age of the patients was 61.1 years old; 56% were male. Low vitamin D status was statistically associated with higher risk of death (RR, 1.60 (95% CI, 1.10–2.32), higher risk of developing severe COVID-19 pneumonia (RR: 1.50; 95% CI, 1.10–2.05). COVID-19 patients with low vitamin D levels had a greater prevalence of hypertension and cardiovascular diseases, abnormally high serum troponin and peak D-dimer levels, as well as elevated interleukin-6 and C-reactive protein than those with serum 25(OH)D levels ≥30 ng/ml. Conclusions: In this meta-analysis, we found a..