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New findings on the role of vitamin D in various conditions, along with recent recommendations from medical societies on vitamin D in the COVID-19 era, have resulted in this week’s top trending clinical topic.
Results of a study published online in the FEBS magazine showed that low plasma vitamin D levels are an independent risk factor for COVID-19 infection and hospitalization (see infographic below). The large population-based study found that a higher proportion of patients who tested positive for COVID-19 had low plasma 25(OH)D concentrations, approximately 90%, compared to 85% of participants who tested negative.
The study also linked low plasma vitamin D levels to an increased risk of hospitalization for COVID-19 infection. Researchers say these findings should prompt doctors to monitor patients’ vitamin D levels regularly, to keep them in the optimal range for overall health and potentially contribute to an immune response to COVID-19.
In terms of specific directions, six medical societies from around the world have recently published joint recommendations which highlight the importance of individuals getting the recommended daily dose of vitamin D during the pandemic. The American Society for Bone and Mineral Research, the Endocrine Society, and the American Association of Clinical Endocrinologists, among others, have published “Joint Guidance on Vitamin D in the Era of COVID-19.”
At the heart of these guidelines is the recommendation to expose the skin directly to sunlight for 15 to 30 minutes per day, while taking care to avoid sunburn. They also noted that supplementing 400 to 1,000 IU per day could help keep levels within the optimal range, especially as outdoor activity decreases given the continued spread of COVID-19.
Recent studies have also examined the role of vitamin D in other conditions. Research published in the journal Cancer showed that taking vitamin D before starting immune checkpoint inhibitor (ICI) treatment reduced the risk of treatment-related colitis. ICIs can significantly improve outcomes for some cancer patients, but can also cause serious inflammatory reactions and immune-related adverse events. The most common and serious of these side effects is colitis. Encouragingly, the study found that vitamin D consumption was linked to a 65% lower risk of developing colitis ICI.
A separate study carried out in the United Kingdom found that higher serum vitamin D concentrations are nonlinearly associated with lower risk of all-cause mortality, cardiovascular disease, and cancer. Results from more than 365,000 participants suggest that thresholds of 45 to 60 nmol/L may represent a potential target for reducing the risk of premature death, which needs to be confirmed in future randomized controlled trials.
From its role in COVID-19 to its relationship to other serious illnesses, vitamin D remains a key part of evolving research, which has helped it become this week’s top trending clinical topic .
Take a short quiz on vitamin D supplementation and deficiency.
