OBJECTIVE

To study the effect of vitamin D concentration on the course and outcomes of COVID-19 in intensive care patients.

MATERIAL AND METHODS

A prospective study included 43 ICU patients admitted to the Sklifosovsky Research Institute for Emergency Care with a confirmed diagnosis of a novel coronavirus infection. Single blood sampling was performed in 1—2 days after admission for analysis of 25-OH D₃ concentration. Patients were divided into 2 groups with normal and reduced level of vitamin D. We analyzed chest CT data and laboratory parameters at admission and at the peak of cytokine storm. Administration of IL-6 antagonists and IL-6 receptor blockers was compared. We also compared the need for respiratory support, period between the onset of disease and respiratory therapy, its total duration and type of respiratory support, incidence of complications (sepsis, multiple organ failure, nosocomial pneumonia, acute kidney injury, thrombosis and hemorrhagic events). We analyzed the outcomes of disease, length of ICU-stay and hospital-stay.

RESULTS

Patients with normal vitamin D level at admission were characterized by lower serum C-reactive protein (15.41±7.96 vs. 63.271±11.988; p=0.029), while lymphocyte count (1.69±0.49 vs. 0.921±0.0719; p=0.029), leukocyte count (7.88±1.33 vs. 5.305±0.468; p=0.041) and serum lactate dehydrogenase (454.50±102.5 vs. 271.315±16.867; p=0.024) were higher. Minimum daily saturation at the peak of cytokine storm was higher in patients with normal vitamin D level (95.2±1.39 vs. 90.947±0.9585; p=0.044).

CONCLUSION

Patients with vitamin D deficiency have a more pronounced inflammatory response in initial stages of disease and more severe lung damage at the stage of cytokine storm. However, this does not increase aggressiveness and duration of respiratory support, ICU- and hospital-stay. There was no worsening of the outcomes too.