Is Vitamin D Deficiency a Factor in C. Diff Diarrhea?

Clostridium difficile-associated diarrhea (CDAD) is an increasingly common cause of inpatient mortality, and recurrent CDAD remains clinically challenging.

Not to mention a 10-day course of treatment—which may or may not be effective—can cost up to $1200.

Researchers from the University of Michigan and the US Department of Veterans Affairs noticed that patients with vitamin D deficiency tend to experience more aggressive CDAD. Since ultraviolet (UV) light exposure boosts vitamin D levels, these researchers designed a study to determine whether higher annual UV light exposure can curb mortality in CDAD patients.

Their ecological study, which was published in the United European Gastroenterology Journal, indicates increasing UV light exposure decreases the risk of inpatient mortality from CDAD.

To identify patients diagnosed and hospitalized with CDAD, the researchers used data from the US National Inpatient Sample from 2004 to 2011, and then linked the patients’ geographic locations to their states’ annual average UV light exposure.

The 2.61 million patients they identified accentuate the magnitude of the CDAD problem. Furthermore, 9% of these patients died.

Those diagnosed with CDAD in Arizona, where sun exposure is high throughout the year, were 16% less likely to die than their counterparts in Michigan, where sun exposure falls sharply in the winter.

The researchers confirmed a seasonal variation in CDAD-related mortality, as well. The highest risk of inpatient mortality occurred between January and March, and the lowest risk occurred between July and September.

The researchers concluded patients diagnosed and hospitalized with CDAD in lower latitudes are significantly less likely to die—an effect that is seasonal, with winter months associated with greater risk of death. Additional studies are needed to confirm these findings.