Two-thirds of children with chronic kidney disease were found to be vitamin D deficient in a new study that suggests a link between the two conditions.
Vitamin D deficiency is common in children with chronic kidney disease (CKD).
Researchers led by Anke Doyon and Franz Schaefer from the University of Heidelberg in Germany looked at how various factors relate to vitamin D levels in 500 children with CKD who were residing in 12 European countries.
They found that two-thirds of the patients were classified as vitamin D deficient.
Patients who took vitamin D supplements had vitamin D levels that were 2 times higher than those who did not take supplements, and they had a lower prevalence of vitamin D deficiency, researchers said.
They also found that vitamin D levels were lower for certain kidney abnormalities, such as glomerulopathies.
Vitamin D levels were lower in winter months than at other times of the year.
"Vitamin D levels are influenced more strongly by seasonal factors, the type of disease and nutritional supplementation than by common variants in vitamin D regulating genes," said Doyon.
"Supplementation practices should be reconsidered and intervention studies are needed to define guidelines how to monitor and treat vitamin D deficiency in children with chronic kidney disease," he said.
The findings were published in the Clinical Journal of the American Society of Nephrology.