Serum myeloperoxidase levels are associated with the future risk of coronary artery disease in apparently healthy individuals: the EPIC-Norfolk Prospective Population Study

J Am Coll Cardiol. 2007 Jul 10;50(2):159-65. doi: 10.1016/j.jacc.2007.03.033. Epub 2007 Jun 21.


Objectives: We evaluated whether serum myeloperoxidase (MPO) levels are associated with the risk of future development of coronary artery disease (CAD) in apparently healthy individuals.

Background: An enzyme of the innate immune system, MPO exhibits a wide array of proatherogenic effects. These include induction of oxidative damage to low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol and promotion of plaque vulnerability. Recent studies revealed that MPO independently predicts adverse outcomes in patients with chest pain or suspected acute coronary syndrome.

Methods: Myeloperoxidase was measured in baseline samples of a case-control study nested in the prospective EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk population study. Case subjects (n = 1,138) were apparently healthy men and women who developed CAD during 8-year follow-up. Control subjects (n = 2,237), matched for age, gender, and enrollment time, remained free of CAD.

Results: The MPO levels were significantly higher in case subjects than in control subjects and correlated with C-reactive protein (CRP) (rho = 0.25; p < 0.001) and white blood cell count (rho = 0.33; p < 0.001). Risk of future CAD increased in consecutive quartiles of MPO concentration, with an odds ratio (OR) of 1.49 in the top versus bottom quartile (95% confidence interval [CI] 1.20 to 1.84; p < 0.001). After adjustment for traditional risk factors, the OR in the top quartile remained significant at 1.36 (95% CI 1.07 to 1.73). Elevated MPO levels (>728 pmol/l) similarly predicted increased risk of future CAD among participants with either LDL-cholesterol <130 mg/dl, HDL-cholesterol >50 mg/dl, or CRP <2.0 mg/l (OR 1.52 [95% CI 1.21 to 1.91], 1.59 [95% CI 1.24 to 2.05], and 1.42 [95% CI 1.14 to 1.77)], respectively).

Conclusion: Elevated MPO levels predict future risk of CAD in apparently healthy individuals. This study suggests that inflammatory activation precedes the onset of overt CAD by many years.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Biomarkers / blood
  • Blood Pressure
  • Case-Control Studies
  • Coronary Artery Disease / blood*
  • Female
  • Humans
  • Lipids / blood
  • Male
  • Middle Aged
  • Peroxidase / blood*
  • Prospective Studies
  • Risk Factors


  • Biomarkers
  • Lipids
  • Peroxidase