Higher levels of blood urea nitrogen (BUN) are associated with increased risk of incident diabetes mellitus. Kidney diseases may increase the risk of diabetes.

- Kidney diseases may increase risk of diabetes.
- Higher levels of blood urea nitrogen heighten the risk for diabetes.
- Blood urea level builds up when kidney function slows down.
Further, the researchers deduced that a likely culprit of the two-way relationship between kidney disease and diabetes is urea. The nitrogen-containing waste product in blood comes from the breakdown of protein in foods. Kidneys normally remove urea from the blood, but it can build up when kidney function slows down.





Kidney diseases increase risk for diabetes
"We have known for a long time that diabetes is a major risk factor for kidney disease, but now we have a better understanding that kidney disease, through elevated levels of urea, also raises the risk of diabetes," said the study's senior author Ziyad Al-Aly, MD, an assistant professor of medicine at Washington University. "When urea builds up in the blood because of kidney dysfunction, increased insulin resistance and impaired insulin secretion often result."
In collaboration with scientists at the St. Louis Veterans Affairs' Clinical Epidemiology Center, Washington University researchers examined medical records in national VA databases to dissect the relationship between kidney disease and diabetes. They evaluated the records of 1.3 million adults without diabetes over a five-year period, beginning in 2003.
Elevated blood urea levels and diabetes
A common blood test that measures the amount of urea nitrogen found in the blood showed that 117,000 of those without diabetes, or 9 percent, had elevated urea levels, signaling poor kidney function.
"That figure, 9 percent of people with high urea levels, remained relatively constant over time," Al-Aly said. "It is also reflective of the general population."
"The risk difference between high and low levels is 688 cases of diabetes per 100,000 people each year," Al-Aly said. "This means that for every 100,000 people, there would be 688 more cases of diabetes each year in those with higher urea levels."
"I read the study with excitement and intrigue, and I thought, 'We have to test this in humans,' " Al-Aly recalled. "Our results were almost an exact replica of the mouse study. The results showed a clear relationship between urea levels and risk of diabetes."
References:
- Yan Xie, Benjamin Bowe et al. Higher Blood Urea Nitrogen is Associated with Increased Risk of Incident Diabetes Mellitus, Kidney International DOI: http://dx.doi.org/10.1016/j.kint.2017.08.033
Source-Eurekalert