Prognostic Value of Ciculating Pregnancy-Associated Plasma Protein-A (PAPP-A) and Proform of Eosinophil Major Basic Protein (pro-MBP) Levels in Patients with Chronic Stable Angina Pectoris

Resumen

Background: The search for markers to improve risk prediction for individuals at risk of developing serious cardiovascular events is ongoing. New markers of coronary artery disease progression have been identified in recent years, among which, circulating levels of pregnancy-associated plasma protein-A (PAPP-A) offer an interesting profile. PAPP-A may play a role in the development of atherosclerotic lesions and represent also a marker of atheromatous plaque instability and extent of cardiovascular disease. PAPP-A has been shown to be a marker of adverse outcome in the acute coronary syndrome. The proform of eosinophil major basic protein (pro-MBP) is the endogenous inhibitor of the proteolytic activity of PAPP-A. PAPP-A levels and PAPP-A/pro-MBP ratio are increased in chronic stable angina (CSA) patients with complex coronary artery stenoses. Little is known however, about the long-term prognostic value of PAPP-A and pro-MBP in “real-life” CSA patients. We sought to assess whether PAPP-A, pro-MBP and PAPP-A/pro-MBP levels predict long-term all-cause mortality in patients with CSA. Methods: We recruited 663 consecutive patients (169 women [25.5 %]; mean age 62.9 ± 9.7 years) undergoing routine diagnostic coronary angiography. Samples for PAPP-A and pro-MBP were taken at study entry. Patients were followed for a median of 8.8 years (interquartile range 3 - 10.6 years). Results: One hundred and six patients (16 %) died during follow-up. On a Cox proportional hazards model, increased PAPP-A concentration (> 4.8 mIU/L) was an independent predictor of the occurrence of all-cause mortality (HR 1.953, 95% CI 1.135-3.360, p = 0.016). Neither pro-MBP nor PAPP-A/pro-MBP ratio were markers of all-cause mortality (p = 0.45 and 0.54, respectively). Conclusions: High PAPP-A levels (> 4.8 mIU/L) showed an association with all-cause mortality during long-term follow-up in patients with CSA. Keywords: PAPP-A, pro-MBP, chronic stable angina, prognosis.