ABSTRACT
BACKGROUND: The modulating effect of vitamin D on cytokine concentrations in severe coronavirus disease 2019 (COVID-19) remains unknown. OBJECTIVES: We aimed to investigate the effect of a single high dose of vitamin D3 on cytokines, chemokines, and growth factor in hospitalized patients with moderate to severe COVID-19. METHODS: This is a post hoc, ancillary, and exploratory analysis from a multicenter, double-blind, placebo-controlled, randomized clinical trial. Patients with moderate to severe COVID-19 were recruited from 2 hospitals in São Paulo, Brazil. Of 240 randomly assigned patients, 200 were assessed in this study and randomly assigned to receive a single oral dose of 200,000 IU vitamin D3 (n = 101) or placebo (n = 99). The primary outcome was hospital length of stay, which has been published in our previous study. The prespecified secondary outcomes were serum concentrations of IL-1ß, IL-6, IL-10, TNF-α, and 25-hydroxyvitamin D. The post hoc exploratory secondary outcomes were IL-4, IL-12p70, IL-17A, IFN-γ, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-8, IFN-inducible protein-10 (IP-10), macrophage inflammatory protein-1ß (MIP-1ß), monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF), and leukocyte count. Generalized estimating equations for repeated measures, with Bonferroni's adjustment, were used for testing all outcomes. RESULTS: The study included 200 patients with a mean ± SD age of 55.5 ± 14.3 y and BMI of 32.2 ± 7.1 kg/m2, of which 109 (54.5%) were male. GM-CSF concentrations showed a significant group-by-time interaction effect (P = 0.04), although the between-group difference at postintervention after Bonferroni's adjustment was not significant. No significant effects were observed for the other outcomes. CONCLUSIONS: The findings do not support the use of a single dose of 200,000 IU vitamin D3, compared with placebo, for the improvement of cytokines, chemokines, and growth factor in hospitalized patients with moderate to severe COVID-19.This trial was registered at clinicaltrials.gov as NCT04449718.