Urine Test Predicts Vein Clot Risk

May 6 -- TUESDAY, May 5 (HealthDay News) -- A higher-than-normal level of the protein albumin in urine indicates an increased risk of dangerous blood clots in the deep veins of the lungs and legs, a Dutch study finds.

These venous thromboembolisms (VTEs) include deep vein thrombosis (DVT), a clotting in the lower extremities which gained recent notoriety when it occurred in passengers on long-haul flights. These clots can become dangerous if they travel to the lungs to produce a pulmonary embolism.

But the presence of albumin in urine might warn of VTE risk, the new study found.

"Microalbuminuria is a known risk factor for arterial conditions such as myocardial infarction [heart attack] and stroke," noted Bakhtawar K. Mahmoodi, a medical student at the University of Groningen who is lead author of a report in the May 6 issue of the Journal of the American Medical Association. "Now it is also found to be a risk factor for venous thromboembolism. This is the first time it has shown to be a risk factor for VTE."

Tests to detect albumin and other proteins in the urine now are commonly done to help assess the risk of problems caused by damage to the arteries, which carry blood from the heart. Those tests now generally are done in people in people known to be at risk because of conditions including diabetes and high blood pressure. Those conditions can reduce the function of kidneys, which remove proteins from the blood.

This latest study indicates that such a urine test could also help assess the risk of problems in the veins, which carry blood back to the heart, said Dr. Ron T. Gansevoort, an associate professor of nephrology at Groningen, who oversaw the research.

The report was based on an ongoing study designed to include all adult residents of Groningen. It included data on almost 8,600 adults, 129 of whom had venous clots during the study period of more than eight years -- an average incidence of 0.14 percent per year.

The incidence of such clots was 40 percent higher for people with slightly elevated urine levels of albumin and more than twice as high for people with more elevated levels than for those with normal levels, after adjustment for known risk factors such as diabetes, the researchers found.