Myeloperoxidase (MPO)

- Elevated MPO levels predict the risk of heart disease in subgroups otherwise associated with low risk

- Elevated MPO levels independently predict the risk of future cardiovascular events in patients presenting with an acute coronary syndrome

- Individuals with elevated MPO levels are more than 2x as likely to experience cardiovascular mortality

- MPO enhances cardiovascular risk prediction when used independently or alongside standard biomarker testing such as hsCRP8

- MPO levels are not likely to be elevated due to chronic infections or rheumatologic disorders due to the fact that free MPO in the blood is a specific marker of vascular inflammation and vulnerable plaque/erosions/fissures.

Treatment Considerations:

These treatment considerations are for educational purposes only. Specific treatment plans should be provided and reviewed by the treating practitioner.

Assess LDL-C levels.

If not at goal, consider lipid-lowering therapy, ideally with a statin-based regimen if not contraindicated.

Assess risk for pre-diabetes/diabetes.

If abnormal fasting glucose or oral glucose tolerance test, consider PPAR agonists, metformin or DPP-IV inhibitor if not contraindicated. 

Assess the presence of coronary artery disease (CAD) with imaging techniques such as carotid intima media thickness testing (CIMT) or coronary artery calcium scoring.

- Consider aspirin therapy if not contraindicated.

- Consider clopidogrel if history of CAD (i.e., myocardial infarction or revascularization) and/or a history of cerebrovascular disease (i.e., TIA or stroke).

Assess dental health (periodontal disease).

Refer to dentist to identify gum disease. NOTE: Poor dental health may cause significant inflammation and is associated with the presence of atherosclerosis.

Assess HDL-C levels.

If not at goal, consider niacin or fenofibrate therapy.

Assess CoQ10 levels.

Recent evidence suggests that low ApoA1 and/or HDL-C levels are associated with low CoQ10 levels10.

Assess smoking habits.

NOTE: Smoking cessation is essential as individuals who smoke are at increased risk of heart disease and blood clots.

Assess blood pressure.

If not at goal, consider initiating, or titrating, anti-hypertensive therapy. NOTE: An elevated blood pressure may contribute to endothelial dysfunction and coronary disease formation.

Assess lifestyle habits.

Consider diet/exercise/weight reduction efforts if appropriate.

Assess the presence of inflammatory conditions such as Crohn’s disease, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

NOTE: Chronic inflammatory diseases may exhibit elevated MPO values due to increased vascular disease associated with these conditions. For example, RA is associated with a 5x increased risk for myocardial infarction.

Assess the presence of vasculitis.

NOTE: MPO values may be elevated in individuals with vasculitis as it is characterized by increased vascular inflammation.

Assess the presence of bone marrow dyscrasias.

NOTE: MPO values may be elevated in individuals with chronic lymphocytic leukemia or other leukemias, that cause increased white blood cell destruction.

Assess level of exercise.

NOTE: MPO values may be elevated in marathon runners and extreme athletes and may identify those with increased oxidative stress and basal levels of inflammation.

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If asymptomatic, with all of the above factors ruled out, an elevated MPO value may in fact be the patient’s baseline. MPO levels should be monitored every 3-6 months.

MPO identifies vulnerable plaque due to the breakdown of cells lining the blood vessels. This breakdown leads to white blood cells attacking the vessel wall and marks the progression of cardiovascular disease. Your result is in the desirable range suggesting that you may have a low probability of plaque rupture if cardiovascular disease is present.

MPO levels are associated with an increased risk for:

- Cardiovascular disease

- Myocardial infarction