The clinical significance of osteopontin on the cardiovascular outcomes in patients with stable coronary artery disease

Background: Osteopontin (OPN) is a noncollagenous matricellular protein which is mainly present in bone matrix. A high OPN level has been associated with heart failure and acute coronary syndrome, however data on patients with chronic coronary syndrome (CCS) are lacking. The present study aimed to evaluate the association between OPN and the prognosis of Taiwanese patients with CCS. Methods: We enrolled participants from the Biosignature Registry, a nationwide prospective cohort study conducted at nine different medical centers throughout Taiwan. The inclusion criteria were participants who had received successful percutaneous coronary intervention at least once previously, and stable under medical therapy for at least 1 month before enrollment. They were followed for at least 72 months. Logistic regression and Cox proportional hazard model were used to investigate the association between OPN and clinical outcomes. The outcomes of this study were the first occurrence of hard cardiovascular events and composite cardiovascular outcomes including cardiovascular mortality, revascularization, hospitalization for acute myocardial infarction (AMI) or heart failure. Results: A total of 666 patients with both hs-CRP and osteopontin measurements were enrolled and followed for 72 months. OPN was correlated positively with AMI-related hospitalization, where the highest tertile (Tertile 3) of baseline OPN had the highest risk of AMI-related hospitalization, which remained significant after multivariate adjustments (HR 3.20, p = 0.017). In contrast, combining OPN and hs-CRP did not improve the prediction of CV outcomes. Conclusion: OPN may be a potentially valuable biomarker in predicting CV outcomes. During 6 years of follow-up period, an OPN level >4810 pg/ml was associated with a significantly higher incidence of AMI-related hospitalization in CCS patients who received successful PCI before the enrollment.