Endocrine Abstracts

Background: Recent studies demonstrated clinical benefits of cholecalciferol supplementation among COVID-19 hospitalized patients. However, features of vitamin D metabolism in the acute phase of SARS-CoV-2 infection remain unclear.

Aim: to estimate the level of 25(OH)D and 1,25(OH)2D as well as oral bolus cholecalciferol supplementation effect on the dynamic of vitamin D metabolites in hospitalized COVID-19 patients.

Materials and Methods: A total of 44 hospitalized patients with confirmed COVID-19 were included in the randomized single-center open-label study. Patients in the Group 1 (n=22) received cholecalciferol bolus supplementation at a total dose of 100,000 IU on the first and the eighth days of hospitalization. Patients from the Group 2 (n=22) did not receive cholecalciferol supplementation. Serum 25(OH)D and 1,25(OH)2D levels were estimated for each group on the first and the ninth day of hospitalization. There were no differences in demographic, clinical, laboratory and instrumental patients` baseline characteristics, as well as in the total dose of concomitant corticosteroid therapy by the 9th day of hospitalization.

Results: On the ninth day of hospitalization 25(OH)D serum level demonstrated the 45.8% rise in the Group 1, while in the Group 2 there was a decrease in the 25(OH)D level by 17.9%. At the same time, dynamic evaluation of the 1.25(OH)2D level did not show any differences between the groups, while pairwise comparison on the first and on the ninth day of hospitalization revealed a significant increase in the active metabolite concentration (P<0.001) in both groups. It was also no significant correlation between the 25(OH)D and 1,25(OH)2 D level at both time points.

Conclusion: Such vitamin D metabolism parameters in the acute period of COVID-19 may be associated with the 1α-hydroxylase activity alteration. Thus, the increase in serum 1.25(OH)2D level despite of vitamin D status dynamic during the hospitalization could be explained either by the COVID-19 course or by the concomitant corticosteroid therapy.