Pregnancy associated plasma protein-A as a marker for myocardial infarction and death in patients with stable coronary artery disease: a prognostic study within the CLARICOR Trial.

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<0.0005), all-cause mortality (HR 2.42, 1.92-3.06, p<0.0005), and myocardial infarction (HR 1.40, 1.01-1.94, p=0.046). After Holm's correction, the latter significance disappeared. After adjustment for risk factors and medication at entry, elevated PAPP-A remained significantly related to the composite outcome (HR 1.51, 1.22-1.86, p<0.0005) and all-cause mortality (HR 1.68, 1.32-2.13, p<0.0005).

CONCLUSION

In patients with stable CAD elevated serum PAPP-A seems promising as aid in identifying patients at high risk for death.