Vitamin D Deficiency Affects 8 in 10 Kidney Transplant Patients, Even in Sunny Climates

Las Vegas, NV - Kidney transplant patients have a very high rate of vitamin D deficiency, even in sunny Southern California, according to new findings presented here at the National Kidney Foundation's 2014 Spring Clinical Meetings.

"Vitamin D deficiency can predispose patients to increased risk of kidney transplant rejection, as vitamin D deficiency causes increased inflammation and may cause T cell activation, and therefore it should be recognized and treated," said Dr. Rahul Dhawan of the University of Southern California in Los Angeles, the lead author of the new study.

Vitamin D insufficiency (between 20 and 30 ng/mL) and deficiency (below 20 ng/mL) are common in the general population, and some small studies have suggested up to 80 percent of kidney transplant patients have vitamin D insufficiency, according to Dr. Dhawan and his colleagues.

To investigate the prevalence among the Southern California kidney transplant population, Dr. Dhawan and his team looked at 53 patients who received kidney transplants at their center in 2013. The patients' vitamin D levels ranged from 8 to 49 ng/mL, with a median of 20 ng/mL. A single patient had a vitamin D level below 10 ng/mL; 26 had levels between 10 and 20 ng/mL; 17 had levels between 20 and 30 ng/mL; and nine had levels above 30 ng/mL.

"Our initial data suggests that approximately 83 percent of our transplant population is vitamin D deficient four weeks after transplantation. These results were surprising, as most of these patients were taking vitamin D supplements. It shows us that we need to be even more aggressive in recognizing and treating deficiency. The tendency for people to spend less time outdoors is a major factor behind vitamin D deficiency overall," Dr. Dhawan said.

"In the kidney transplant group, these patients are in a predicament because due to the medications they take to prevent transplant rejection, they are at increased risk of cancer, specifically skin cancer. Therefore, they are encouraged not to be in the sun, predisposing them to vitamin D deficiency," said Thomas Manley, director of scientific activities at the National Kidney Foundation.

"Vitamin D deficiency is prevalent in the post-transplant population and there is growing evidence that low vitamin D levels are associated with poor health outcomes in both the general population and those with kidney disease," continued Manley. "Kidney transplantation improves many of the physiologic abnormalities of chronic kidney disease-mineral and bone disorder) commonly seen with progressive kidney dysfunction, but based on this study, evaluating Vitamin D levels and supplementing when appropriate is an important consideration in this population."

The National Kidney Foundation is the leading organization in the U.S. dedicated to the awareness, prevention and treatment of kidney disease for hundreds of thousands of healthcare professionals, millions of patients and their families, and tens of millions of Americans at risk. For more information, visit www.kidney.org.