Zahra Khorasanchi - Department of Nutrition, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.Student Research Committee, faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

Background: Coronavirus (COVID-۱۹) has affected more than ۲۱۸ million individuals globally, leading to >۴ million deaths. Vitamin D (Vit-D) has immune-modulating effects that modify the inflammatory response. This study aimed to evaluate the effects of high-dose Vit-D supplementation on inflammatory markers in COVID-۱۹.Method: This double-blinded randomized clinical-trial was conducted on ۱۴۰ hospitalized patients aged >۳۰ years. Patients were randomly allocated to one of two groups: intervention with a single dose of ۵۰,۰۰۰ IU of Vit-D capsules and daily ۱۰,۰۰۰ IU Vit-D orally syrup from the second day of admission for ۲۹ days (n=۷۰) and control with the intake of ۱۰۰۰ IU Vit-D syrup orally per day for ۳۰ days (n=۷۰). Blood samples were taken at baseline and the end of the intervention. Neutrophil-Lymphocyte Ratio (NLR) and C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and Red Cell Distribution Width (RDW) were evaluated. The decision tree analysis was undertaken using JMP Pro (SAS) version ۱۳.Result: the average age in the intervention and control groups was ۵۹.۹۶±۱۳.۴۴ and ۶۰.۸۲±۱۳.۸۵ years, respectively. There was a significant time×group effect for of CRP (p=۰.۰۲۱) and NLR (p=۰.۰۴۸). This finding indicates that the changes in these variables over time were significantly different between the intervention and control groups. The decision tree analysis showed that age was most important factor to predict responding to patients’ vitamin D treatment. Also it has also been shown that if a man is younger than ۷۳ year old and NLR is more than ۳.۸, there is a ۹۰% probability that he will respond better to vitamin D therapy.Conclusion: Our results showed that a high dose of Vit-D supplementation positively affected inflammatory markers in COVID-۱۹. Further randomized-control trials are needed to confirm the effects of Vit-D in COVID-۱۹ in different clinical stages of this disease.

Vitamin D, COVID-۱۹, Inflammatory factors, Nutrition, Supplementation