Many people who follow news developments in cardiac health have heard about C-reactive protein (CRP), a marker of inflammation that is associated with an increased risk of coronary heart disease and stroke.
Fewer people are familiar with PLAC, a relatively new blood test that measures the presence of another inflammatory marker, an enzyme called lipoprotein-associated phospholipase A2 and abbreviated Lp-PLA2.
A 14-year follow-up of the MONICA study, which assessed the incidence of heart disease in 21 countries over a 10-year period, showed that people with the highest blood levels of Lp-PLA2 had a two times greater risk of coronary heart disease than those with the lowest levels of the enzyme. Another study called ARIC, which studied populations in four U.S. communities, showed that people with the highest levels of both CRP and Lp-PLA2 had a 10-fold greater risk of a stroke.
It's not entirely clear whether the PLAC test yields information in addition to that provided by measurements of CRP, but some individuals have elevated levels of Lp-PLA2 despite normal levels of CRP.
To better assess your risk, your doctor may order a PLAC test, which was approved in 2003 by the Food and Drug Administration as a marker for future coronary heart disease.
