Vitamin D levels and intensive care unit outcomes of a cohort of critically ill COVID-19 patients

This observational study suggests that a high proportion (70.3%) of patients hospitalized with COVID-19 had vitamin-D deficiency that the general UK population, however, there were no measurable differences in overall clinical outcomes between those with normal and deficient vitamin-D levels.

165 patients testing positive for SARS COVID-19 who were admitted to the University Hospital Southampton England from March to June 2020, who had their plasma vitamin D levels measured. Fifty of those were admitted to the ICU.

To evaluate  a cohort of critically ill COVID-19 patients admitted to the hospital to examine any associations between vitamin D levels and the severity of illness and clinical outcomes.

This hospital used a standardized cut off value for the plasma vitamin-D level of 50 nmol/L. Forty-nine patients (29.7%) had normal levels (>50 nmol/L) and the rest (70.3%) had vitamin-D deficiency (<50 nmol/L). A greater proportion (82%) of critically ill COVID-19 patients had vitamin-D deficiency compared to those not requiring ICU admission (65.2%). Among the ICU patients, low vitamin D level (<50 nmol/L) was associated with younger age and markers indicative of higher viral loads. However, there were no significant differences in ICU clinical outcomes (invasive and non-invasive mechanical ventilation, acute kidney injury and mechanical ventilation and hospital days) between patients with low and normal vitamin-D levels.

Any conclusions from this study should be considered with caution because this was a small single center observational study. Although the study did not show any significant differences in clinical outcomes based on vitamin-D levels, these results may be due to the small sample size or other variables such as patient-specific risk factors, ICU interventions and bacterial co-infections that may influence the overall clinical outcomes more than vitamin-D levels alone.

Despite the association of low vitamin-D levels with low CT values, there is no difference in clinical outcomes in this small cohort of critically ill COVID-19 patients. The complex relationship between vitamin-D levels and COVID-19 infection needs further exploration with large scale randomized controlled trials.

An observational cohort study 

Orchard L, Baldry M, Nasim-Mohi M, Monck C, Saeed K, Grocott MPW, Ahilanandan D; University Hospital Southampton Critical Care Team and the REACT COVID Investigators. Vitamin D levels and intensive care unit outcomes of a cohort of critically ill COVID-19 patients. Clin Chem Lab Med. 2021 Jan 18. doi: 10.1515/cclm-2020-1567. Epub ahead of print. PMID: 33554566. https://pubmed.ncbi.nlm.nih.gov/33554566/