The PLAC Test: A New Predictor of Cardiovascular Risk?
Author: Jenna Brinks, M.S., Exercise Physiologist, Beaumont, Royal Oak
Publish Date: 12/12/2008
What is the PLAC Test?
The PLAC Test is a simple blood test that measures the amount of lipoprotein-associated phospholipase A2, or Lp-PLA2, an enzyme associated with inflammation in the walls of your arteries. Elevated levels of this enzyme indicate an increased risk of heart attack and stroke. Recently, the Food and Drug Administration endorsed the PLAC Test as a valuable blood test to aid in assessing risk for coronary artery disease and ischemic stroke.
How is the PLAC Test different from other tests used to assess cardiovascular disease risk?
When circulating cholesterol causes fatty deposits (plaques) to form on the walls of your arteries, they become inflamed. In response to this inflammation, our bodies produce Lp-PLA2. Elevated levels of Lp-PLA2 indicate that plaques may be more likely to rupture, potentially causing a heart attack or stroke.
There are other blood tests that measure inflammation within the body, such as high sensitivity C-reactive protein, or hs-CRP. C-reactive protein is not as sensitive to inflammation of the artery walls because it can also be affected by other factors, such as complications from diabetes and obesity. The PLAC Test, on the other hand, measures an enzyme produced within the plaques of artery walls, making it an even more accurate indicator of arterial inflammation.
What do my results indicate?
PLAC Test results are categorized into three progressive levels of cardiovascular risk: low, < 200 ng/ dL; moderate, 200-235 ng/dL; and, high, > 235 ng/dL. According to one report, if your PLAC Test reveals an Lp-PLA2 level of< 160 ng/dl, you have a less than 1% annual risk of a cardiovascular event! Another study conducted by the Mayo Clinic found that 95% of coronary patients who had Lp-PLA2 levels below 200 ng/dL did not have either a heart attack or stroke over a 4-year follow-up period. If you have an elevated PLAC Test, this may signal the need for more aggressive risk factor reduction therapy, including a further lowering of your low-density lipoprotein cholesterol level. Only you and your doctor can decide the best approach to your care, and the PLAC Test can help guide those decisions.
How can I have the PLAC Test?
Like all other tests and blood work, your physician must write a prescription for the PLAC Test. There is no preparation required before a PLAC Test. You do not need to be fasting, and you can take your medications as directed.
Will insurance cover the PLAC Test?
In many instances, yes! All health insurance plans vary, so it is important to find out if your insurance plan covers this blood test. Medicare currently reimburses for this test when medically necessary.
According to Dr. Michael Davidson, Lp-PLA2 is directly involved in the formulation and development of atherosclerotic plaque progression and may not only be a biomarker for risk prediction, but may also represent a novel therapeutic target to reduce the disease process (American Journal of Cardiology, Supplement, June 2008). If you are interested in additional information about the PLAC Test, you can visit www.plactest.com, or speak with your primary care physician or cardiologist.
Jenna Brinks, M.S., Exercise Physiologist, Beaumont Hospital - Royal Oak