A recent publication suggested patients’ vitamin D levels may impact the severity of their COVID-19 symptoms.1 EHR data for 28,185 patients for whom both COVID-19 disease status and vitamin D deficiency status were known show no statistically significant difference in the risk of COVID-19 infection, hospitalization, or mortality between vitamin D deficient and non-vitamin D deficient patients.2
The prevalence of COVID-19 infections was not significantly different between patients who were vitamin D deficient (27.9%) and those who were not (26.7%). For patients who were COVID-19 positive, hospitalization rates were similar for those with vitamin D deficiency and those without vitamin D deficiency (19.5% and 21.2%, respectively), and though the difference in mortality rates (5.8% and 8.2%, respectively) was larger, our population was too small to verify the statistical significance of this difference. Figure 1 illustrates these findings.
Because screening for vitamin D deficiency is not done routinely, testing for vitamin D levels is more likely to occur when deficiency is suspected. In this analysis, 86% of all patients with known vitamin D status were found to be vitamin D deficient.
Existing literature suggests vitamin D deficiency and severe COVID-19 disease share some of the same risk factors, such as patient age over 65, chronic kidney disease, obesity, and institutional living.3,4
A future study that includes a representative sample of patients with normal vitamin D levels could provide a deeper understanding of the impact vitamin D deficiency has on COVID-19 severity. Additionally, future studies are also needed to assess what, if any, role vitamin D supplementation has in the prevention or treatment of COVID-19.
Data are pooled from 52 health systems representing 259 hospitals that span 26 states and cover 15 million patients.
1Daneshkhah, A et al. The Possible Role of Vitamin D in Suppressing Cytokine Storm and Associated Mortality in COVID-19 Patients. medRxiv. May 18, 2020. https://doi.org/10.1101/2020.04.08.20058578
2The X2 test was used as test of statistical significance.
3Parva NR, Tadepalli S, Singh P, et al. Prevalence of Vitamin D Deficiency and Associated Risk Factors in the US Population (2011-2012). Cureus. 2018;10(6):e2741. Published 2018 Jun 5. doi:10.7759/cureus.2741
4People Who Are at Higher Risk for Severe Illness. CDC. https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-at-higher-risk.html