Influence of plasma fibrinogen levels on the incidence of myocardial infarction and death is modified by other inflammation-sensitive proteins - A long-term cohort study

Inflammation may play an important role in atherosclerotic disease. Plasma fibrinogen is an established predictor of cardiovascular events. The aim of this study was to evaluate whether other inflammation-sensitive plasma pro teins modify this prediction. We studied the incidence of cardiac events an d death in men in relation to fibrinogen levels alone and in combination wi th other proteins. The study was based on 6075 men, who were, on average, 4 6 years old at the time of the screening examination, which included the qu antitative assessment of plasma levels of fibrinogen, orosomucoid, alpha (1 )-antitrypsin, haptoglobin, and ceruloplasmin. The concentration of each pr otein was divided into quartiles for each. This classification made it poss ible to identify 4 groups, ie, men in the first fibrinogen quartile and at the same time either not belonging to the fourth quartile of any of the oth er proteins (Q1/No group) or also belonging to the fourth quartile of great er than or equal to1 of the additional proteins (Q1/Yes group) and correspo nding groups in the fourth fibrinogen quartile (Q4/No and Q4/Yes groups). D uring the follow-up, which occurred at an average of 16 years, 439 (7.2%) m en experienced a cardiac event, and 653 (10.7%) died; 278 of these men died of cardiovascular diseases, with 206 deaths attributed to ischemic heart d isease. From the lowest to the highest quartile, there was for each protein a stepwise increase in the incidence of cardiac events and mortality. All- cause mortality and cardiovascular mortality were significantly higher in t he Q4/Yes group compared with the Q4/No group, but they were similar in the Q4/No and Q1/Yes groups. The incidence of cardiac events was significantly higher in the Q1/Yes and Q4/Yes groups compared with the Q1/No and Q4/No g roups, respectively. The increased cardiovascular mortality and cardiac eve nt rates remained after adjustment for several confounders when the Q4/Yes and Q4/No groups were compared. The results suggest that the incidence of c ardiac events and death due to cardiovascular diseases in middle-aged men p redicted by plasma levels of fibrinogen is modified by other inflammation-s ensitive proteins.