Low 25-Hydroxyvitamin D Levels on Admission to the Intensive Care Unit May Predispose COVID-19 Pneumonia Patients to a Higher 28-Day Mortality Risk: A Pilot Study on a Greek ICU Cohort

Although the results of this small pilot study suggest a connection between vitamin D status and clinical outcomes in critically ill COVID-19 patients admitted to the ICU, it is challenging to draw conclusions because of the limitations of the study.

Critically ill patients of Greek ethnicity, suffering from COVID-19 pneumonia, who were directly admitted to the ICU of the “Evangelismos” General Hospital from 22 March to 3 August 2020. The study tracked 30 ICU patients in whom 25(OH)D was measured on ICU admission.

This was a pilot study of a very small number of people of Greek ethnicity only at a single hospital. No statistical analysis was performed to assess other factors that may have influenced vitamin D or clinical outcomes. Study subjects received only one measurement of vitamin D status and it was obtained upon ICU admission. While the results do suggest a connection between vitamin D deficiency and COVID-19 mortality, extrapolation is extremely limited.

All patients who died within 28 days belonged to the low vitamin D group. Survival analysis showed that the low vitamin D group had a higher 28-day survival absence probability (log-rank test, p = 0.01). Critically ill COVID-19 patients who died in the ICU within 28 days appeared to have lower 25(OH)D levels upon ICU admission compared to survivors. When the cohort was divided at the median 25(OH)D value, the low vitamin D group had an increased risk of 28-day mortality.

In this observational, single center study, we demonstrated that COVID-19 non-survivors had lower ICU admission 25(OH)D levels compared to survivors, implying a possible association of low 25(OH)D levels with poor prognosis of COVID-19 pneumonia patients.

Prospective, observational study. Eighty (80%) percent of patients had vitamin D deficiency upon their admission to the ICU, and the remaining exhibited insufficiency. Based on 25(OH)D levels, patients were stratified in two groups: higher and lower than the median value of the cohort (15.2 ng/mL). The two groups did not differ in their demographic or clinical characteristics.

Vassiliou AG, Jahaj E, Pratikaki M, Orfanos SE, Dimopoulou I, Kotanidou A. Low 25-Hydroxyvitamin D Levels on Admission to the Intensive Care Unit May Predispose COVID-19 Pneumonia Patients to a Higher 28-Day Mortality Risk: A Pilot Study on a Greek ICU Cohort. Nutrients. 2020 Dec 9;12(12):3773. doi: 10.3390/nu12123773. PMID: 33316914;https://pubmed.ncbi.nlm.nih.gov/33316914/