WASHINGTON (AP) - Doctors are getting a new blood test to help predict which people with low cholesterol are at risk for heart disease.
The Food and Drug Administration approved the PLAC test Friday. It works by measuring an enzyme active in the inflammatory process, one known as Lp-PLA2.
In a federally financed study, researchers tracked more than 1,300 middle-aged people for nine years to see who was most at risk of developing heart disease.
Of most interest were people considered at very low risk of heart disease because they had normal levels of the so-called bad cholesterol, or LDL cholesterol - levels below 130.
When those low-cholesterol patients had high levels of Lp-PLA2, however, they were twice as likely to develop heart disease, said lead researcher Dr. Christie Ballantyne of Baylor College of Medicine.
Add another measure of risk - a separate inflammatory protein called C-reactive protein - to a high Lp-PLA2 level, and the risk of heart disease tripled, he said.
Between one-third and half of heart attacks occur in people who do not have high cholesterol, so scientists have long hunted ways to find which of those people were at risk in time to help them.
The PLAC test promises to be one tool to do that, Ballantyne said.
The laboratory test is made by diaDexus Inc. of San Francisco. The company wouldn't reveal a price but said it would be competitive with testing for C-reative protein, which is roughly $16.
