Whether dietary supplementation with vitamin D is beneficial, in terms of preventing disease, has been controversial. However, vitamin D has been reported to increaseÂ immune cellsâ€™ production of microbe-fighting proteins. That’s why Emory doctorsÂ have been testing whether high doses of vitamin D couldÂ be helpful for critical care patients, who need to ward off infections.
The results of a small-scale clinical trial, presented in Denver this week at the American Thoracic Society meeting, suggest thatÂ high doses of vitamin D could decrease the length of hospital stays in critically ill patients with respiratory failure.
Hospitalized patients often have insufficient levels of vitamin D because of the lack of physical activity and exposure to the sun.Â The 31 patients participating in Emoryâ€™s randomized clinical trial were divided into three groups. Two of the groups received high doses of vitamin D3 (a total of 250,000 or 500,000 international units over five days), and one received a placebo.
â€œThese dosages were significantly higher than normal daily doses and were intended to quickly restore vitamin D levels in patients who have low levels,â€ says Jenny Han, MD, assistant professor of medicine, Emory University School of Medicine. Hanâ€™s research career has focused on defining the relationship between vitamin D status and infection.
Study participants who received a placebo had an average blood level of 21 ng/ml vitamin D. The Endocrine Society defines deficiency as less than 20 ng/ml and insufficiency as between 20 and 30 ng/ml.
Hospital length of stay went down with the higher dose of vitamin D (average 36 days for placebo, 25 days for lower dose, 18 days for higher dose). This difference was statistically significant.
The length of stay in intensive care also tended to decrease (average 23 days for placebo, 18 days for lower dose vitamin D, 15 days for higher dose vitamin D), but the change was not statistically significant. A similar result was observed for duration of ventilator support.
The majority of the patients in the study had severe sepsis or septic shock; 43 percent had some type of infection upon admission. Some had cardiovascular or neurologic diseases.
â€œThese data can inform the design of a larger, adequately powered randomized controlled trial on the efficacy of high-dose vitamin D3 on host immunity and other indices associated with recovery,â€ the authors conclude.
Caveat: Emory investigators also recently found that low vitamin D levels were not connected to the risk of hospital-acquired infections, and another study found thatÂ high-dose vitamin D did not reduce ICUÂ length of stay.