Healthy adults with high levels of phosphate in their blood are 50 percent more likely to have increased levels of calcium in the coronary arteries, which is a key indicator of future cardiovascular risk, says new research.

The findings, which will be published in the February 2009 issue of the Journal of the American Society of Nephrology, studied the phosphate levels of young adults with an average age of 25. Researchers followed up with a CT scan 15 years later.

The results showed that those with high levels of phosphate at age 25 were 50 percent more likely to have high levels of calcium in their coronary arteries at age 40.

Because it was not an experimental study, it cannot establish a cause-and-effect relationship between phosphate levels and coronary artery calcium.

However, Dr. Robert N. Foley of the University of Minnesota says the study helps in the understanding of risk factors associated with heart disease and may help patients and doctors monitor them.

Another study, in the same issue of JASN, found that high phosphate levels in patients with moderate chronic kidney disease also have higher levels of calcium in coronary arteries.