OBJECTIVE: Pregnancy associated plasma protein-A (PAPP-A) is a potential new marker for vulnerable plaques in the coronary arteries only examined in stable coronary disease (CAD) in patients undergoing coronary angiography. Here we address the prognostic value of serum PAPP-A in unselected stable CAD patients. METHOD: Blood samples were drawn at study entry. Serum PAPP-A values =4mIU/L were considered elevated. Mortality and non-fatal myocardial infarction was prospectively registered. The primary outcome was the composite outcome of myocardial infarction and all-cause mortality, secondary outcomes were all-cause mortality and myocardial infarction. RESULTS: Patients (n=4243) were followed for a median of 2.8 years. In a Cox analysis, elevated PAPP-A was significantly related to the composite outcome of myocardial infarction and death (HR 1.99, 95% CI 1.62-2.45, p