Relation of fibrinogen level with cardiovascular events in patients with coronary artery disease

Evidence on the usefulness of fibrinogen for the risk stratification of patients with coronary artery disease remains inconclusive. The aims of this study were to investigate the association of fibrinogen with cardiovascular events and to assess whether this biomarker provides additional prognostic information on top of that provided by traditional cardiovascular risk factors. This study included 13,195 patients with angiography-proved coronary artery disease and fibrinogen measurements available. Receiver-operating characteristic curve analysis showed that the best fibrinogen cutoff for mortality prediction was 402.0 mg/dl. On the basis of this cutoff, patients were divided into 2 groups: the group with fibrinogen >402.0 mg/dl (n = 5,198) and the group with fibrinogen ≤402.0 mg/dl (n = 7,997). The primary outcome was 1-year mortality. All-cause deaths occurred in 393 patients with fibrinogen >402.0 mg/dl and in 246 patients with fibrinogen ≤402.0 mg/dl (Kaplan-Meier estimates of mortality 7.7% and 3.1%, log-rank test p <0.001). The relation between fibrinogen and mortality followed a J-shaped pattern, with lowest mortality in patients with fibrinogen concentrations of 295 to 369 mg/dl. After adjustment for cardiovascular risk factors and relevant clinical variables, fibrinogen remained an independent correlate of all-cause mortality (adjusted hazard ratio 1.07, 95% confidence interval 1.04 to 1.10, p <0.001, for each 50 mg/dl increase in fibrinogen level), but it did not improve the discriminatory power of the model for mortality prediction (integrated discrimination improvement 0.002, p = 0.32). In conclusion, in patients with coronary artery disease, fibrinogen is an independent correlate of mortality, but it does not provide additional prognostic information on top of that provided by traditional cardiovascular risk factors.