Osteopontin as a novel prognostic marker in stable ischaemic heart disease: a 3‐year follow‐up study

Abstract

Osteopontin (OPN) is a glycoprotein, which may play a major role in the regulation of biological phenomena. Increased levels of OPN have been linked to the presence and to the severity of atherosclerosis. This study was undertaken to assess the prognostic significance of plasma OPN levels in patients with stable ischaemic heart disease (IHD). In 101 patients with stable IHD and angiographically documented significant coronary artery stenosis, plasma OPN levels were measured at baseline (time of coronary arteriography). Patients were prospectively followed for a median time of 3 years (minimum 2.25, maximum 3.9 years). The primary study endpoint was the composite of cardiovascular death, non-fatal myocardial infarction, need for revascularization and hospitalization for cardiovascular reasons. Baseline lnOPN levels were directly related to age (r = 0.27, P < 0.001) and inversely to left ventricular ejection fraction (r = -0.32, P < 0.01). Left ventricular ejection fraction was an independent predictor of plasma OPN levels after adjustment for age and gender (beta = -0.013, P = 0.02). Median OPN value was 55 ng mL(-1). In the univariate Cox-regression analysis, OPN levels > 55 ng mL(-1) (n = 50) were significantly related to adverse cardiac outcome (HR = 2.40, 95% CI: 1.11-5.23, P = 0.027). In multivariate model, OPN levels > 55 ng mL(-1) remained statistically significant independent predictor of adverse outcome after adjustment for age, gender, left ventricular ejection fraction and the number of diseased coronary arteries (HR = 2.88, 95% CI: 1.09-7.58, P = 0.032). OPN may provide significant prognostic information independent of other traditional prognostic markers in patients with stable IHD.