Even a small amount of a protein called albumin in the urine of patients with stable coronary artery disease increases their risk of cardiovascular death, say U.S. researchers.

The findings from this study of almost 3,000 patients, age 50 and older, with stable coronary artery disease (CAD) have implications for assessing and perhaps treating patients with vascular disease.

The study was published in the current issue of the journal Circulation.

Albumin is normal and necessary in blood, but its presence in urine indicates leakage in the kidney filtration system and possible damage to cells that line the kidney’s blood vessels, according to background information in the study.

“We found that virtually any degree of albuminuria, even albumin below the level we call microalbuminuria, placed a patient at significantly higher risk of cardiovascular events,” lead author Dr. Scott D. Solomon, associate professor of medicine at Harvard Medical School and director of Noninvasive Cardiology at Brigham and Women’s Hospital in Boston, said in a prepared statement.

He and his colleagues also found that the hypertension drug trandolapril (an ACE inhibitor) lowered albumin levels in patients’ urine.

The findings of this study and previous research by the same team indicate that “we cardiologists need to pay more attention to kidney function in our patients, and we need to look at two aspects — filtration and albuminuria,” Solomon said.

“It is important for cardiologists to understand that these are not patients who will even come to dialysis or even necessarily see a nephrologist,” he said. “But they do have mild kidney disease that puts them at increased risk for a cardiovascular event.”

(Source: NHIC)