Background: The prognostic influences of fibrinogen and C-reactive protein levels and their relations to myocardial damage in unstable coronary artery syndromes have not been well described.
Methods and results: Fibrinogen and C-reactive protein were determined at inclusion and related to outcome after 5 months in 965 patients with unstable angina or non-Q-wave myocardial infarction randomized to 5 weeks with low-molecular-weight heparin or placebo. The probabilities of death were 1.6%, 4.6%, and 6.9% (P=.005) and the probabilities of death and/or myocardial infarction were 9.3%, 14.2%, and 19.1% (P=.002), respectively, in patients stratified by tertiles of fibrinogen (< 3.38, 3.38 to 3.99, and > or = 4.0 g/L). The probabilities of death were 2.2%, 3.6%, and 7.5% (P=.003) after stratification of patient data by tertiles of C-reactive protein level (< 2, 2 to 10, and > 10 mg/L). In logistic multiple regression analysis, increased fibrinogen levels were independently associated with the incidence of death and/or myocardial infarction (P=.013), and elevated C-reactive protein level was associated with the incidence of death (P=.012). The increased relative risk of subsequent death or myocardial infarction in individuals with an elevated fibrinogen level was consistent in most subgroups evaluated; although significantly so only in patients with signs of myocardial damage.
Conclusions: Increased levels of both fibrinogen and C-reactive protein are associated with a worse outcome in patients with unstable coronary artery disease. The increased risk associated with elevated fibrinogen levels is independent of, and additive to, the prognostic influence of myocardial damage.