Identification of novel diagnostic and prognostic biomarkers for abdominal aortic aneurysm.

Abdominal aortic aneurysm is a life-threatening condition due to the risk of aneurysm growth and rupture. There are no approved diagnostic or prognostic biomarkers for abdominal aortic aneurysm. We aimed to identify diagnostic and prognostic biomarkers for abdominal aortic aneurysm and to investigate their relationship with abdominal aortic aneurysm diameter and growth. In this case-control study, patients were included from an abdominal aortic aneurysm screening study on men aged ≥65 years. Of 24,589 examined men, 415 had abdominal aortic aneurysm, out of whom 134 consented to participate in the present study. One hundred and thirty-six screened men with aortic diameter <30 mm, matched for comorbidities and time of sampling were included as non-abdominal aortic aneurysm patients. Ninety-one cardiovascular specific proteins in plasma samples were measured by the Proseek Multiplex CVD III After Bonferroni correction, plasma levels of 21 proteins associated with proteolysis, oxidative-stress, lipid metabolism, and inflammation were significantly increased, whereas levels of paraoxonase 3, associated with high-density lipoprotein metabolism, were decreased in abdominal aortic aneurysm patients. Combination of growth/differentiation factor 15 and cystatin B had the best ability to discriminate abdominal aortic aneurysm from non-abdominal aortic aneurysm (area under the curve, 0.76; sensitivity, 80% and specificity, 52%). Myeloperoxidase showed the best prognostic value (area under the curve, 0.71; sensitivity, 80% and specificity, 59%) and higher baseline levels of myeloperoxidase were significantly associated with faster abdominal aortic aneurysm growth compared with lower levels, independent of baseline diameter. We have identified multiple proteins associated with abdominal aortic aneurysm diameter and growth with a potential to become novel diagnostic and prognostic biomarkers for abdominal aortic aneurysm.