Abstract 5929: Osteopontin Predicts Mortality in Patients With Pulmonary Hypertension
Background: The extracellular matrix protein Osteopontin (OPN) was found upregulated in several animal models of cardiac failure and appears to play an important role in myocardial remodeling. Moreover, our group recently showed that OPN plasma level are elevated in patients with left ventricular dysfunction and predict an adverse prognosis. Since right ventricular dysfunction is an important predictor of morbidity and mortality in patients with pulmonary hypertension (PH), we now tested the diagnostic and prognostic power of OPN in this patient cohort.
Methods: We included 101 patients with PH of different etiology in this study, while 40 healthy individuals of similar age and sex distribution served as controls. OPN plasma levels were determined by ELISA and assessed for correlation with clinical severity, echocardiographic parameters of right ventricular dysfunction, right ventricular remodeling and prognosis.
Results: Median OPN was significantly elevated in patients with PH compared to healthy controls (776 ng/ml vs. 382 ng/ml; p<0.0001). Furthermore, OPN levels were higher in patients with moderate to severe right heart failure compared to patients with no or mild symptoms (WHO Fc III/IV 903 ng/ml vs. WHO Fc I/II 650 ng/ml; p<0.001). In addition to that, OPN plasma levels not only showed a positive correlation with the right ventricular enddiastolic diameter (r=0.46; p<0.0001), but were also significantly higher in patients with impaired right ventricular function (903 ng/ml vs 591 ng/ml; p<0.0001). Finally, in a multivariate analysis including clinical, demographical and biochemical parameters, such as NT-proBNP, OPN levels above the Median emerged as an independent predictor of all cause mortality (HR 11.6; 95%-CI 1.46 –96.7; p<0.02).
Conclusion: In summary, our data show for the first time that OPN plasma levels are not only elevated in patients with PH, but also correlate with clinical status and right ventricular remodelling. Preliminary data also suggest that OPN is predictive for right ventricular dysfunction and an adverse prognosis in PH. OPN might therefore be useful in the non invasive monitoring of patients with PH.