Severe vitamin D deficiency in people with COVID-19 associated with greater risk of death than those with normal levels.

Vitamin D is a fat-soluble vitamin that is stored in the liver and fatty tissues of the body. Perhaps best known for its role in maintaining calcium balance and bone health, vitamin D plays critical roles in immune function. Recent evidence suggests that vitamin D deficiency is associated with poor outcomes in COVID-19. Findings from a new study suggest that poor vitamin D status increases the risk of death from COVID-19.

The authors of the retrospective, observational study analyzed data collected from 42 patients with acute respiratory failure due to COVID-19 who were treated in Bari, Italy, during a six-week period during the spring of 2020. The authors of the study classified the patients according to their vitamin D status: normal, insufficient, moderate deficiency, or severe deficiency. According to the Endocrine Society, vitamin D concentrations less than 20 ng/mL (50 nmol/L) define “deficiency,” and concentrations ranging from 52.5 to 72.5 nmol/L (21 to 29 ng/mL) define “insufficiency.”

They found that 81 percent of the patients had low vitamin D status. After ten days of of hospitalization, patients with severe vitamin D deficiency were 50 percent more likely to die, while those with vitamin D levels greater than or equal to 10 ng/mL had a 5 percent chance of death.

These findings indicate that severe vitamin D deficiency may predict poor prognosis in patients with poor vitamin D status, suggesting that adjunctive treatment that involves vitamin D repletion might improve disease outcomes. Learn more about the role of vitamin D in COVID-19 in this clip featuring Dr. Rhonda Patrick.

• Link to full study.