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Also known as: LpPLA2; Lp-PLA2 Activity Test; Platelet-activating Factor Acetylhydrolase; PAF-AH; PLAC
Formal name: Lipoprotein-associated Phospholipase A2

At a Glance

Why Get Tested?

To help determine your risk of developing cardiovascular disease (CVD), including your risk of coronary heart disease (CHD), and ischemic stroke

When to Get Tested?

When your healthcare provider determines that you are at a moderate to high risk of developing CVD or of having an ischemic stroke; when you have a family history of CVD or CHD

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?


The Test Sample

What is being tested?

Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an enzyme that appears to play a role in the inflammation of blood vessels and is thought to help promote atherosclerosis. This test measures the amount and activity of Lp-PLA2 in the blood.

Some recent studies have shown that Lp-PLA2 is an independent risk marker for cardiovascular disease (CVD), including coronary heart disease (CHD), and ischemic stroke. In these studies, increased concentrations of Lp-PLA2 were seen in many people who were diagnosed with CHD and ischemic stroke, regardless of other risk factors. These findings make this relatively new test potentially useful as one of a growing number of cardiac risk markers that are used to help determine a person's risk of developing CVD.

CVD causes more deaths in the U.S. each year than any other cause, according to the Centers for Disease Control and Prevention. CHD and ischemic stroke are both associated with the buildup of unstable fatty plaque deposits in the arteries that can lead to blockages in blood vessels and to heart attacks or brain damage. There are a variety of risk factors that have been identified as being associated with both conditions, including high blood pressure, diabetes, metabolic syndrome, smoking, obesity, high cholesterol levels, increased LDL (low-density lipoprotein, the "bad cholesterol"), and decreased HDL (high-density lipoprotein, the "good cholesterol").

Many people who have one or more of the commonly recognized risk factors will eventually develop CVD, but a significant number of people who have few or none of these risk factors will also develop CVD. This has lead researchers to look for additional markers that might identify those at increased risk of CVD.

In addition to the traditional risk factors listed above, a low level of chronic, systemic inflammation and blood vessel (vascular) inflammation are thought to contribute to overall risk for developing CVD. The hs-CRP test is associated with systemic inflammation; high levels are associated with increased CVD risk. The Lp-PLA2 test is associated with vascular inflammation, and high levels are thought to increase the chance of cardiovascular events, including heart attack or stroke.

How is the sample collected for testing?

A blood sample is obtained by inserting a needle into a vein in the arm.

NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.

Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.

The Test

Common Questions

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Article Sources

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NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.

Sources Used in Current Review

White H, et. al. Changes in Lipoprotein‐Associated Phospholipase A2 Activity Predict Coronary Events and Partly Account for the Treatment Effect of Pravastatin: Results From the Long‐term Intervention with Pravastatin in Ischemic Disease Study. J Am Heart Assoc. 2013 October; 2(5): e000360. Available online at through Accessed December 2013.

O'Riordan, M. (2010 April 29). Modest association between Lp-PLA2 and coronary heart disease. Medscape Multispecialty [On-line information]. Available online at through Accessed March 2014.

(© 1995-2014). Lipoprotein Associated Phospholipase A2 (PLAC). Mayo Clinic Mayo Medical Laboratories [On-line information]. Available online at through Accessed March 2014.

Sultan, S. and Elkind, M. (Updated 2013 October 31). Genetic and Inflammatory Mechanisms in Stroke. Medscape Reference [On-line information]. Available online at through Accessed March 2014.

(2013 November). Lipoprotein-Associated Phospholipase A2: How Effective as a Risk Marker of Cardiovascular Disease and as a Therapeutic Target? BioPortfolio [On-line information]. Available online at through Accessed November 2013.

Delgado, J. et. al. (Updated 2014 March). Cardiovascular Disease (Non-traditional Risk Markers) - Risk Markers - CVD (Non-traditional). ARUP Consult [On-line information]. Available online at through Accessed March 2014.

Zalewski, A. et. al. (2006 September). Lp-PLA2: A New Kid on the Block. Clinical Chemistry v 52 (9) 1645-1650. [On-line information]. Available online at through Accessed March 2014.

Pagana, K. D. & Pagana, T. J. (© 2011). Mosby's Diagnostic and Laboratory Test Reference 10th Edition: Mosby, Inc., Saint Louis, MO. Pg 621.

(©2012) American Association of Clinical Endocrinologists' Guidelines for Management of Dyslipidemia and Prevention of Atherosclerosis. Available online at through Accessed March 2014.

Maiolino G, et al (October 31, 2013). Lipoprotein-Associated Phospholipase A2 Activity Predicts Cardiovascular Events in High Risk Coronary Artery Disease Patients. PLoS One. 2012; 7(10): e48171. Available online at through Accessed March 2014.

(April 26 2012) New Clinical Endocrinology Guidelines Support Lp-PLA2 Measurement For Risk Assessment of Coronary Artery Disease. Press Release, Reuters. Available online at through Accessed March 2014.

Sources Used in Previous Reviews

Wu, A. (© 2006). Tietz Clinical Guide to Laboratory Tests, 4th Edition: Saunders Elsevier, St. Louis, MO. Pp 682-683.

O'Riordan, M. (2008 February 27). Elevated Lp-PLA2 Levels Predict Incident CHD Independent of Traditional Risk Factors. Medscape Today from Heartwire [On-line information]. Available online at through Accessed May 2009.

Boero, L. et. al. (2009 April 01). Alterations in Biomarkers of Cardiovascular Disease in Active Acromegaly. Medscape Today from Clinical Endocrinology [On-line information]. Available online at through Accessed May 2009.

(Updated 2009 May). The Physician's Guide to Laboratory Test Selection and Interpretation, Cardiovascular Disease (Non-traditional Risk Markers) - Risk Markers - CVD (Non-traditional). ARUP Consult [On-line information]. Available online at through Accessed May 2009.

(2007 July). Lipoprotein-Associated Phospholipase A2 (PLAC™). ARUP Technical Bulletin [On-line information]. Available online through . Accessed May 2009.

(Reviewed 2007 November). Lp-PLA2 Test Summary. Quest Diagnostics Interpretive Guide [On-line information]. Available online at through Accessed May 2009.

Elkind, M. et. al. (2006 June 14). Genetic and Inflammatory Mechanisms in Stroke. eMedicine [On-line information]. Available online at through Accessed May 2009.

Lusky, K. (2008 July). New clue for predicting stroke risk: Lp-PLA2. CAP Today [On-line information]. Available online through Accessed May 2009.

Persson, M. et. al. (2007 June). Elevated Lp-PLA2 Levels Add Prognostic Information to the Metabolic Syndrome on Incidence of Cardiovascular Events Among Middle-Aged Nondiabetic Subjects. Arteriosclerosis, Thrombosis, and Vascular Biology. 2007;27:1411 [On-line information]. Available online at through Accessed May 2009.

What are the Types of Stroke? American Stroke Association [On-line information]. Available online at through Accessed May 2009.