The effect of supplementation with vitamins A, B, C, D, and E on disease severity and inflammatory responses in patients with COVID-19: a randomized clinical trial

BACKGROUND AND OBJECTIVE: Because of the effect of vitamins on modulating the immune system function, we have evaluated the effect of supplementation with vitamins A, B, C, D, and E in ICU-admitted patients with COVID-19. METHODS: This study was a randomized and single-blinded clinical trial in which 60 subjects were randomly assigned to two groups. The intervention group (n=30) received vitamins, and the control group did not receive any vitamin or placebo. The intervention was included 25,000 IU daily of vitamins A, 600,000 IU once during the study of D, 300 IU twice daily of E, 500 mg four times daily of C, and one amp daily of B complex for 7 days. At baseline and after the 7-day intervention, the serum levels of inflammatory markers, vitamins, and the SOFA score were assessed. In addition, the mortality rate and duration of hospitalization were evaluated after the intervention (IRCT registration number: IRCT20200319046819N1/registration date: 2020-04-04, https://www.irct.ir/trial/46838). RESULTS: Significant changes were detected in serum levels of vitamins (p < 0.001 for all vitamins), ESR (p < 0.001), CRP (p = 0.001), IL6 (p = 0.003), TNF-a (p = 0.001), and SOFA score (p < 0.001) after intervention compared with the control group. The effect of vitamins on the mortality rate was not statistically significant (p=0.112). The prolonged hospitalization rate to more than 7 days was significantly lower in the intervention group than the control group (p=0.001). Regarding the effect size, there was a significant and inverse association between receiving the intervention and prolonged hospitalization (OR = 0.135, 95% CI 0.038–0.481; p=0.002); however, after adjusting for confounders, it was not significant (OR=0.402, 95% CI 0.086–1.883; p=0.247). CONCLUSION: Supplementation with vitamins A, B, C, D, and E could improve the inflammatory response and decrease the severity of disease in ICU-admitted patients with COVID-19.