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Vitamin D Deficiency and Outcome of COVID-19 Patients

Take Home Message

In this study, of German patients, an association was reported between Vitamin D status, severity of COVID-19 and mortality from the disease.


  • Hospitalized patients were older, were predominantly male, and had substantially more comorbid conditions.
  • A total of 41 (22%) patients were VitD-deficient (<12 ng/mL) and 118 (64%) patients had VitD levels < 20 ng/mL.
  • Median VitD level was significantly lower in the inpatient versus the outpatient subgroup. A higher proportion of inpatients was VitD-deficient (VitD < 12 ng/mL).
  • Median follow-up was 66 days (range 2–92 days).
  • A total of 16 patients died and 23 patients required invasive mechanical ventilation.
  • Median age and hospitalization rate was higher and more patients required (intensive) oxygen therapy in those that were vitamin D deficient. The findings were similar in the subgroup of hospitalized patients.
  • In VitD-deficient patients, median IL-6 levels (a marker of systemic inflammation) at hospitalization were significantly higher (70.5 versus 29.7 pg/mL.
  • In the outpatient subgroup, no differences between VitD-deficient patients and patients with VitD levels ≥ 12 ng/mL were observed.
  • Adjusting for age, gender, and comorbidities, VitD deficiency was associated with higher risk of IMV/D and death


185 consecutive symptomatic SARS-CoV-2-positive patients admitted to the Medical University Hospital Heidelberg. Ninety-two (50%) patients were followed in the outpatient setting and 93 (50%) patients required hospitalization.

Things to Keep in Mind

This was a single-center, retrospective, and observational study. Potential confounders like obesity (as reflected by the body mass index) or other specific comorbidities were not considered. No causal association between VitD deficiency and severity/outcome of COVID-19 can be concluded.

Author’s Conclusions

This observational study among patients with COVID-19 who have experienced a definite outcome shows an association between VitD status and severity of and mortality from COVID-19. Prospective, randomized controlled studies on VitD supplementation in SARS-CoV-2 infected individuals are highly warranted.

Study Design

  • Date was taken retrospectively from a prospective non-interventional register.
  • Vitaming D (VitD) status at first presentation was assessed retrospectively using accredited laboratory methods.
  • VitD deficiency was defined as serum total 25-hydroxyvitamin D level < 12 ng/mL (<30 nM). Primary endpoint was severe course of disease (i.e., need for invasive mechanical ventilation and/or death, IMV/D).


Radujkovic A, Hippchen T, Tiwari-Heckler S, Dreher S, Boxberger M, Merle U. Vitamin D Deficiency and Outcome of COVID-19 Patients. Nutrients. 2020 Sep 10;12(9):2757. doi: 10.3390/nu12092757. PMID: 32927735; PMCID: PMC7551780.

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Research Summaries

Changes in 25‐hydroxyvitamin D levels post‐vitamin D supplementation in people of Black and Asian ethnicities and its implications during COVID‐19 pandemic: A systematic review

Changes in 25‐hydroxyvitamin D levels post‐vitamin D supplementation in people of Black and Asian ethnicities and its implications during COVID‐19

Vitamin D insufficiency in COVID-19 and influenza A, and critical illness survivors: a cross-sectional study

Take Home Message Vitamin D deficiency/insufficiency was present in majority of hospitalized patients with COVID-19 or influenza A and correlated with severity and persisted in critical illness survivors at concentrations expected