Vitamin D deficiency may increase risk of mortality in intensive care patients

Apr 4 2012

Scientists have long believed that vitamin D, which is naturally absorbed from sunlight, has an important role in the functioning of the body's autoimmune system. Now Prof. Howard Amital of Tel Aviv University's Sackler Faculty of Medicine and Sheba Medical Center has discovered that the vitamin may also affect the outcomes of patients in intensive care.

In a six-month study, Prof. Amital and his colleagues found that patients who had a vitamin D deficiency lived an average of 8.9 days less than those who were found to have sufficient vitamin D. Vitamin D levels also correlated with the level of white blood cells which fight disease.

The study, which was published in the journal QJM: An International Journal of Medicine, demonstrates further research into giving patients vitamin D could confirm that it will improve their survival outcomes.

To measure the impact of vitamin D levels on the survival of critically ill patients, the researchers designed an observational study. Over the course of six months, 130 patients over the age of 18 admitted to an intensive care unit of a TAU-affiliated hospital and requiring mechanical ventilation were admitted to the study. Patients who had taken vitamin D supplements prior to admittance were excluded from the study population.

Upon admittance, patients were divided into two groups based on vitamin D concentration: those who had 20 nanograms or more of the vitamin - the amount defined as the National Institute of Health as sufficient - and those who were vitamin D deficient based on the same criteria. In total, 107 patients suffered from vitamin D deficiency.

Survival curves indicate that while patients with sufficient vitamin D survived an average of 24.2 days, those who were deemed to be deficient in vitamin D survived an average of only 15.3 days - patients with sufficient vitamin D levels survived an average of 8.9 days longer. They were also found to have a better WBC count.

These findings merit further investigation, Prof. Amital says. He suggests that the effects of vitamin D supplementation in critically ill patients be further assessed in future studies. The initial results indicate only that vitamin D concentration may be an indicator of survival, he says.

But don't wait until you're in poor health to start taking vitamin D, suggests Prof. Amital. Vitamin D appears to enhance the function of the immune system in numerous ways, and it's becoming clear that it does have an impact on overall health and well-being.

According to research, including an article in the New England Journal of Medicine, the majority of those who live in North America and other Western countries are known to be vitamin D deficient due to limited exposure to the sun. But even if the springtime skies are gray, supplements from the pharmacy shelf will have the same benefits, Prof. Amital says.

Source: American Friends of Tel Aviv University