Vitamin D levels and in-hospital mortality of COVID-19

Introduction: Vitamin D deficiency may be linked to an increased susceptibility risk of COVID-19. However, the data on the link between vitamin D levels and COVID-19 related in-hospital mortality is debatable. This study investigated whether vitamin D levels are associated with intensive care unit (ICU) admission and COVID-19 related in-hospital mortality. Material and Method: We conducted a retrospective study with hospitalized COVID-19 patients between March 2020 and March 2021. 25 OH Vitamin D (Vit-D) levels <12 ng/mL were accepted as Vit-D deficiency. The patients were evaluated in two groups as Vit-D deficient and Non-Vit-D deficient. Groups were matched 1:1 by propensity score matching (PSM) regarding age and gender. Results: A total of 192 patients, 52.6% (101) of whom were female, with a median age of 71 (IQR:61-78), were included in the study. Before PSM analysis, the Vit-D deficient group patients were older, female predominant, have more mortality rates. After PSM, 122 cases (61 cases for each group) remained, and mortality between Vit-D groups was statistically similar (34% vs. 26%, p=0.32). In the univariate logistics regression analysis before PSM, Vit-D level was a significant for mortality (OR:0.972 CI:0.945-0.999, p=0.044); after PSM statistical significance was lost (OR:0.96 CI:0.934-1.005, p=0.087). ICU admission rates were similar between groups. Conclusion: Although mortality was higher in the group with Vit-D deficiency in the first analysis, it lost its significance on mortality after adjusting groups for age and gender. There was no relationship between vitamin D deficiency and COVID-19 in-hospital mortality.